Reorganize top-level directories with clearer naming convention

app -> app-desktop-macos, presets -> app-presets, server -> remote-server,
daw-config-reaper -> osc-config-daw, plugin-reaper-realearn -> plugin-reaper-relearn.
Updated run.py and presets.py path references accordingly.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>

plugin-reaper-relearn/pot/Cargo.toml

@@ -0,0 +1,48 @@
+[package]
+name = "pot"
+version = "0.1.0"
+authors = ["Benjamin Klum <benjamin.klum@helgoboss.org>"]
+edition = "2021"
+publish = false
+
+[dependencies]
+# Own
+base.workspace = true
+reaper-high.workspace = true
+reaper-medium.workspace = true
+helgobox-api.workspace = true
+rppxml-parser.workspace = true
+
+# 3rd-party
+enumset.workspace = true
+itertools.workspace = true
+wildmatch.workspace = true
+serde.workspace = true
+derive_more.workspace = true
+tokio.workspace = true
+enum-map.workspace = true
+once_cell.workspace = true
+lexical-sort.workspace = true
+strum.workspace = true
+splitty.workspace = true
+rust-ini.workspace = true
+walkdir.workspace = true
+either.workspace = true
+riff-io.workspace = true
+rusqlite = { workspace = true, features = ["bundled"] }
+rmp-serde.workspace = true
+serde_json.workspace = true
+dirs.workspace = true
+futures.workspace = true
+derivative.workspace = true
+tempfile.workspace = true
+sanitize-filename.workspace = true
+tracing.workspace = true
+regex.workspace = true
+nanoid.workspace = true
+chrono.workspace = true
+anyhow.workspace = true
+camino.workspace = true
+
+[lints.clippy]
+enum_glob_use = "deny"

plugin-reaper-relearn/pot/src/api.rs

@@ -0,0 +1,710 @@
+use crate::plugins::ProductKind;
+use crate::provider_database::{
+    DatabaseId, FIL_HAS_PREVIEW_TRUE, FIL_IS_FAVORITE_TRUE, FIL_IS_USER_PRESET_FALSE,
+    FIL_IS_USER_PRESET_TRUE,
+};
+use crate::{FilterItem, PotPreset};
+use enum_map::EnumMap;
+use enumset::EnumSet;
+use helgobox_api::persistence::PotFilterKind;
+use once_cell::sync::Lazy;
+use std::collections::HashSet;
+
+use base::hash_util::{NonCryptoHashMap, NonCryptoHashSet};
+use std::fmt;
+use std::fmt::{Display, Formatter, Write};
+use std::str::FromStr;
+use strum::IntoEnumIterator;
+
+/// An ID for uniquely identifying a preset along with its corresponding database.
+///
+/// This ID is stable only at runtime and only until the database is refreshed.
+#[derive(Copy, Clone, Eq, PartialEq, Hash, Debug)]
+pub struct PresetId {
+    pub database_id: DatabaseId,
+    pub preset_id: InnerPresetId,
+}
+
+impl PresetId {
+    pub fn new(database_id: DatabaseId, preset_id: InnerPresetId) -> Self {
+        Self {
+            database_id,
+            preset_id,
+        }
+    }
+}
+
+/// An ID for uniquely identifying a preset within a certain database.
+///
+/// This ID is stable only at runtime and only until the database is refreshed.
+#[derive(Copy, Clone, Eq, PartialEq, Hash, Debug, serde::Serialize, serde::Deserialize)]
+pub struct InnerPresetId(pub u32);
+
+#[derive(Copy, Clone, Eq, PartialEq, Hash, Debug, Default)]
+pub struct FilterItemId(pub Option<Fil>);
+
+impl FilterItemId {
+    pub const NONE: Self = Self(None);
+}
+
+/// Filter value.
+///
+/// These can be understood as possible types of a filter item kind. Not all types make sense
+/// for a particular filter item kind.
+///
+/// Many of these types are not suitable for persistence because their values are not stable.
+#[derive(Copy, Clone, Eq, PartialEq, Hash, Debug)]
+pub enum Fil {
+    /// A typical integer filter value to refer to a filter item in a specific Komplete database.
+    ///
+    /// Makes sense for all filter kinds supported by Komplete.
+    ///
+    /// This needs a pot filter item kind and a specific Komplete database to make full sense.
+    /// The integers are not suited for being persisted because different Komplete scans can yield
+    /// different integers! So they should only be used at runtime and translated to something
+    /// more stable for persistence.
+    Komplete(u32),
+    /// Refers to a specific pot database.
+    ///
+    /// Only makes sense for the pot filter kind "Database".
+    ///
+    /// Only valid at runtime, not suitable for persistence.
+    Database(DatabaseId),
+    /// Refers to something that can be true of false, e.g. "favorite" or "not favorite"
+    /// or "available" or "not available".
+    ///
+    /// Makes sense for all boolean filter kinds.
+    ///
+    /// Suitable for persistence.
+    Boolean(bool),
+    /// Refers to a kind of product.
+    ///
+    /// Only makes sense for the pot filter kind "Product kind".
+    ProductKind(ProductKind),
+    /// Refers to a product.
+    ///
+    /// Only makes sense for the pot filter kind "Product".
+    ///
+    /// Not suitable for persistence because product IDs are created at runtime.
+    Product(ProductId),
+    /// Refers to a project.
+    ///
+    /// Only makes sense for the pot filter kind "Project".
+    ///
+    /// Not suitable for persistence because project IDs are created at runtime.
+    Project(ProjectId),
+}
+
+/// Runtime ID for a [`Product`].
+#[derive(Copy, Clone, Eq, PartialEq, Ord, PartialOrd, Hash, Debug, derive_more::Display)]
+pub struct ProductId(pub u32);
+
+/// Runtime ID for a REAPER project.
+#[derive(Copy, Clone, Eq, PartialEq, Ord, PartialOrd, Hash, Debug, derive_more::Display)]
+pub struct ProjectId(pub u32);
+
+pub type FilterItemCollections = GenericFilterItemCollections<FilterItem>;
+
+#[derive(Debug)]
+pub struct GenericFilterItemCollections<T>(EnumMap<PotFilterKind, Vec<T>>);
+
+pub trait HasFilterItemId {
+    fn id(&self) -> FilterItemId;
+}
+
+impl HasFilterItemId for FilterItem {
+    fn id(&self) -> FilterItemId {
+        self.id
+    }
+}
+
+impl<T> Default for GenericFilterItemCollections<T> {
+    fn default() -> Self {
+        Self(enum_map::enum_map! { _ => vec![] })
+    }
+}
+
+impl<T> GenericFilterItemCollections<T> {
+    pub fn empty() -> Self {
+        Default::default()
+    }
+
+    pub fn get(&self, kind: PotFilterKind) -> &[T] {
+        &self.0[kind]
+    }
+
+    pub fn iter_mut(&mut self) -> impl Iterator<Item = (PotFilterKind, &mut Vec<T>)> {
+        self.0.iter_mut()
+    }
+
+    pub fn set(&mut self, kind: PotFilterKind, items: Vec<T>) {
+        self.0[kind] = items;
+    }
+
+    pub fn extend(&mut self, kind: PotFilterKind, items: impl Iterator<Item = T>) {
+        self.0[kind].extend(items);
+    }
+
+    pub fn are_filled_already(&self) -> bool {
+        // Just take any of of the constant filters that should be filled.
+        !self.get(PotFilterKind::IsFavorite).is_empty()
+    }
+}
+
+impl<T> IntoIterator for GenericFilterItemCollections<T> {
+    type Item = (PotFilterKind, Vec<T>);
+    type IntoIter = <EnumMap<PotFilterKind, Vec<T>> as IntoIterator>::IntoIter;
+
+    fn into_iter(self) -> Self::IntoIter {
+        self.0.into_iter()
+    }
+}
+
+impl<T: HasFilterItemId> GenericFilterItemCollections<T> {
+    pub fn narrow_down(&mut self, kind: PotFilterKind, includes: &NonCryptoHashSet<FilterItemId>) {
+        self.0[kind].retain(|item| includes.contains(&item.id()))
+    }
+}
+
+/// `Some` means a filter is set (can also be the `<None>` filter).
+/// `None` means no filter is set (`<Any>`).
+pub type OptFilter = Option<FilterItemId>;
+
+#[derive(Copy, Clone, Debug, Default)]
+pub struct Filters(EnumMap<PotFilterKind, OptFilter>);
+
+impl Filters {
+    pub fn empty() -> Self {
+        Self::default()
+    }
+
+    pub fn wants_preview(&self) -> Option<bool> {
+        if let Some(FilterItemId(Some(fil))) = self.get(PotFilterKind::HasPreview) {
+            Some(fil == FIL_HAS_PREVIEW_TRUE)
+        } else {
+            None
+        }
+    }
+
+    pub fn database_matches(&self, db_id: DatabaseId) -> bool {
+        self.matches(PotFilterKind::Database, Fil::Database(db_id))
+    }
+
+    pub fn wants_user_presets_only(&self) -> bool {
+        self.wants_only(PotFilterKind::IsUser, FIL_IS_USER_PRESET_TRUE)
+    }
+
+    pub fn wants_factory_presets_only(&self) -> bool {
+        self.wants_only(PotFilterKind::IsUser, FIL_IS_USER_PRESET_FALSE)
+    }
+
+    pub fn wants_favorites_only(&self) -> bool {
+        self.wants_only(PotFilterKind::IsFavorite, FIL_IS_FAVORITE_TRUE)
+    }
+
+    pub fn any_unsupported_filter_is_set_to_concrete_value(
+        &self,
+        supported_advanced_kinds: EnumSet<PotFilterKind>,
+    ) -> bool {
+        let supported_kinds = supported_advanced_kinds.union(PotFilterKind::core_kinds());
+        supported_kinds
+            .complement()
+            .iter()
+            .any(|k| self.is_set_to_concrete_value(k))
+    }
+
+    /// To be used with filter kinds where `<None>` is **not** a valid filter value. In this case,
+    /// <None> is considered an invalid value and it never matches (no reason to panic but almost).
+    pub fn matches(&self, kind: PotFilterKind, fil: Fil) -> bool {
+        match self.get(kind) {
+            None => true,
+            Some(FilterItemId(None)) => false,
+            Some(FilterItemId(Some(wanted_fil))) => fil == wanted_fil,
+        }
+    }
+
+    pub fn favorite_matches(
+        &self,
+        favorites: &NonCryptoHashSet<InnerPresetId>,
+        preset_id: InnerPresetId,
+    ) -> bool {
+        match self.get(PotFilterKind::IsFavorite) {
+            None => true,
+            Some(FilterItemId(None)) => false,
+            Some(FilterItemId(Some(fil))) => {
+                if fil == FIL_IS_FAVORITE_TRUE {
+                    favorites.contains(&preset_id)
+                } else {
+                    !favorites.contains(&preset_id)
+                }
+            }
+        }
+    }
+
+    /// To be used with filter kinds where `<None>` is a valid filter value.
+    pub fn matches_optional(&self, kind: PotFilterKind, fil: Option<Fil>) -> bool {
+        match self.get(kind) {
+            // <Any>
+            None => true,
+            // <None> or a specific value
+            Some(FilterItemId(wanted_fil)) => fil == wanted_fil,
+        }
+    }
+
+    fn wants_only(&self, kind: PotFilterKind, fil: Fil) -> bool {
+        self.get(kind) == Some(FilterItemId(Some(fil)))
+    }
+
+    /// Returns `false` if set to `None`
+    pub fn is_set_to_concrete_value(&self, kind: PotFilterKind) -> bool {
+        matches!(self.0[kind], Some(FilterItemId(Some(_))))
+    }
+
+    pub fn get(&self, kind: PotFilterKind) -> OptFilter {
+        self.0[kind]
+    }
+
+    pub fn get_ref(&self, kind: PotFilterKind) -> &OptFilter {
+        &self.0[kind]
+    }
+
+    pub fn set(&mut self, kind: PotFilterKind, value: OptFilter) {
+        self.0[kind] = value;
+    }
+
+    pub fn effective_sub_bank(&self) -> &OptFilter {
+        self.effective_sub_item(PotFilterKind::Bank, PotFilterKind::SubBank)
+    }
+
+    pub fn clear_excluded_ones(&mut self, exclude_list: &PotFilterExcludes) {
+        for kind in PotFilterKind::iter() {
+            if let Some(id) = self.0[kind] {
+                if exclude_list.contains(kind, id) {
+                    self.0[kind] = None;
+                }
+            }
+        }
+    }
+
+    pub fn clear_if_not_available_anymore(
+        &mut self,
+        affected_kinds: EnumSet<PotFilterKind>,
+        collections: &FilterItemCollections,
+    ) {
+        for kind in affected_kinds {
+            if let Some(id) = self.0[kind] {
+                let valid_items = collections.get(kind);
+                if !valid_items.iter().any(|item| item.id == id) {
+                    self.0[kind] = None;
+                }
+            }
+        }
+    }
+
+    pub fn iter(&self) -> impl Iterator<Item = (PotFilterKind, OptFilter)> {
+        self.0.into_iter()
+    }
+
+    pub fn effective_sub_category(&self) -> &OptFilter {
+        self.effective_sub_item(PotFilterKind::Category, PotFilterKind::SubCategory)
+    }
+
+    pub fn clear_this_and_dependent_filters(&mut self, kind: PotFilterKind) {
+        self.set(kind, None);
+        for dependent_kind in kind.dependent_kinds() {
+            self.set(dependent_kind, None);
+        }
+    }
+
+    fn effective_sub_item(
+        &self,
+        parent_kind: PotFilterKind,
+        sub_kind: PotFilterKind,
+    ) -> &OptFilter {
+        let category = &self.0[parent_kind];
+        if category == &Some(FilterItemId::NONE) {
+            category
+        } else {
+            &self.0[sub_kind]
+        }
+    }
+}
+
+#[derive(Debug, Default)]
+pub struct PotFavorites {
+    favorites: NonCryptoHashMap<DatabaseId, NonCryptoHashSet<InnerPresetId>>,
+}
+
+impl PotFavorites {
+    pub fn is_favorite(&self, preset_id: PresetId) -> bool {
+        if let Some(db_favorites) = self.favorites.get(&preset_id.database_id) {
+            db_favorites.contains(&preset_id.preset_id)
+        } else {
+            false
+        }
+    }
+
+    pub fn toggle_favorite(&mut self, preset_id: PresetId) {
+        let db_favorites = self.favorites.entry(preset_id.database_id).or_default();
+        if db_favorites.contains(&preset_id.preset_id) {
+            db_favorites.remove(&preset_id.preset_id);
+        } else {
+            db_favorites.insert(preset_id.preset_id);
+        }
+    }
+
+    pub fn db_favorites(&self, db_id: DatabaseId) -> &NonCryptoHashSet<InnerPresetId> {
+        static EMPTY_HASH_SET: Lazy<NonCryptoHashSet<InnerPresetId>> = Lazy::new(HashSet::default);
+        self.favorites.get(&db_id).unwrap_or(&EMPTY_HASH_SET)
+    }
+}
+
+#[derive(Clone, Debug, Default)]
+pub struct PotFilterExcludes {
+    exluded_items: EnumMap<PotFilterKind, NonCryptoHashSet<FilterItemId>>,
+}
+
+impl PotFilterExcludes {
+    pub fn contains(&self, kind: PotFilterKind, id: FilterItemId) -> bool {
+        self.exluded_items[kind].contains(&id)
+    }
+
+    pub fn remove(&mut self, kind: PotFilterKind, id: FilterItemId) {
+        self.exluded_items[kind].remove(&id);
+    }
+
+    pub fn add(&mut self, kind: PotFilterKind, id: FilterItemId) {
+        self.exluded_items[kind].insert(id);
+    }
+
+    pub fn is_empty(&self, kind: PotFilterKind) -> bool {
+        self.exluded_items[kind].is_empty()
+    }
+
+    pub fn contains_database(&self, db_id: DatabaseId) -> bool {
+        self.contains(
+            PotFilterKind::Database,
+            FilterItemId(Some(Fil::Database(db_id))),
+        )
+    }
+
+    pub fn contains_product(&self, product_id: Option<ProductId>) -> bool {
+        self.contains(
+            PotFilterKind::Bank,
+            FilterItemId(product_id.map(Fil::Product)),
+        )
+    }
+
+    pub fn normal_excludes_by_kind(&self, kind: PotFilterKind) -> impl Iterator<Item = &Fil> + '_ {
+        self.exluded_items[kind]
+            .iter()
+            .filter_map(|id| id.0.as_ref())
+    }
+
+    pub fn contains_none(&self, kind: PotFilterKind) -> bool {
+        self.exluded_items[kind].contains(&FilterItemId::NONE)
+    }
+}
+
+#[derive(Debug)]
+pub struct CurrentPreset {
+    pub preset: PotPreset,
+    pub macro_param_banks: Vec<MacroParamBank>,
+}
+
+#[derive(Debug)]
+pub struct MacroParamBank {
+    params: Vec<MacroParam>,
+}
+
+impl MacroParamBank {
+    pub fn new(params: Vec<MacroParam>) -> Self {
+        Self { params }
+    }
+
+    pub fn name(&self) -> String {
+        let mut name = String::with_capacity(32);
+        for p in &self.params {
+            if let Some(section) = &p.section {
+                name += " / ";
+                name += section;
+            }
+        }
+        name
+    }
+
+    /// Returns the index of the section to which the parameter in the given slot belongs.
+    pub fn resolve_param_section_index(&self, slot_index: u32) -> Option<u32> {
+        self.params[0..=slot_index as usize]
+            .iter()
+            .filter(|param| param.section.is_some())
+            .enumerate()
+            .map(|(i, _)| i as u32)
+            .last()
+    }
+
+    /// Returns the section to which the parameter in the given slot belongs.
+    ///
+    /// The parameter itself only carries its section name if it's the beginning of a new section.
+    pub fn resolve_param_section(&self, slot_index: u32) -> Option<&str> {
+        // Search from right to left
+        self.params[0..=slot_index as usize]
+            .iter()
+            .rev()
+            .find_map(|param| Some(param.section.as_ref()?.as_str()))
+    }
+
+    pub fn params(&self) -> &[MacroParam] {
+        &self.params
+    }
+
+    pub fn params_mut(&mut self) -> &mut [MacroParam] {
+        &mut self.params
+    }
+
+    pub fn find_macro_param_at(&self, slot_index: u32) -> Option<&MacroParam> {
+        self.params.get(slot_index as usize)
+    }
+
+    /// Returns slot index and param.
+    pub fn find_first_param_with_fx_param_index(&self, index: u32) -> Option<(u32, &MacroParam)> {
+        self.params.iter().enumerate().find_map(|(i, p)| {
+            let resolved_index = p.fx_param?.resolved_param_index?;
+            if index == resolved_index {
+                Some((i as u32, p))
+            } else {
+                None
+            }
+        })
+    }
+
+    pub fn param_count(&self) -> u32 {
+        self.params.len() as _
+    }
+}
+
+#[derive(Clone, Debug)]
+pub struct MacroParam {
+    pub name: String,
+    /// The parameter itself only carries its section name if it's the beginning of a new section.
+    pub section: Option<String>,
+    pub fx_param: Option<PotFxParam>,
+}
+
+#[derive(Copy, Clone, Debug)]
+pub struct PotFxParam {
+    pub param_id: PotFxParamId,
+    /// Only resolved on demand (when the FX is available).
+    pub resolved_param_index: Option<u32>,
+}
+
+#[derive(Copy, Clone, Debug, derive_more::Display)]
+pub enum PotFxParamId {
+    /// Positional/index ID.
+    ///
+    /// Some plug-in standards such as VST2 only support positional IDs.
+    Index(u32),
+    /// Real ID, independent of the position.
+    ///
+    /// Supported by VST3 plug-ins.
+    Id(u32),
+}
+
+impl CurrentPreset {
+    pub fn preset(&self) -> &PotPreset {
+        &self.preset
+    }
+
+    pub fn find_macro_param_bank_at(&self, bank_index: u32) -> Option<&MacroParamBank> {
+        self.macro_param_banks.get(bank_index as usize)
+    }
+
+    /// Finds macro parameters across all banks, assuming a bank size of exactly 8.
+    pub fn find_macro_param_at(&self, slot_index: u32) -> Option<&MacroParam> {
+        let bank_index = slot_index / 8;
+        let bank_slot_index = slot_index % 8;
+        self.find_bank_macro_param_at(bank_index, bank_slot_index)
+    }
+
+    pub fn find_bank_macro_param_at(
+        &self,
+        bank_index: u32,
+        bank_slot_index: u32,
+    ) -> Option<&MacroParam> {
+        self.macro_param_banks
+            .get(bank_index as usize)?
+            .find_macro_param_at(bank_slot_index)
+    }
+
+    /// Returns bank, slot index and param.
+    pub fn find_first_macro_param_with_fx_param_index(
+        &self,
+        index: u32,
+    ) -> Option<(&MacroParamBank, u32, &MacroParam)> {
+        self.macro_param_banks.iter().find_map(|b| {
+            let (i, p) = b.find_first_param_with_fx_param_index(index)?;
+            Some((b, i, p))
+        })
+    }
+
+    pub fn macro_param_bank_count(&self) -> u32 {
+        self.macro_param_banks.len() as _
+    }
+
+    pub fn has_params(&self) -> bool {
+        !self.macro_param_banks.is_empty()
+    }
+}
+
+#[derive(Clone, Eq, PartialEq, Debug)]
+pub struct PersistentDatabaseId(String);
+
+impl PersistentDatabaseId {
+    pub fn random() -> Self {
+        Self(nanoid::nanoid!())
+    }
+
+    pub const fn new(raw_id: String) -> Self {
+        PersistentDatabaseId(raw_id)
+    }
+
+    pub fn get(&self) -> &str {
+        &self.0
+    }
+}
+
+#[derive(Clone, Eq, PartialEq, Debug)]
+pub struct PersistentInnerPresetId(String);
+
+impl PersistentInnerPresetId {
+    pub fn new(raw_id: String) -> Self {
+        Self(raw_id)
+    }
+
+    pub fn get(&self) -> &str {
+        &self.0
+    }
+}
+
+/// A preset ID that survives restarts and rescans.
+///
+/// It's more expensive to clone, hash etc. than [`PresetId`]. That's why we should only use it
+/// for purposes where persistence matters, e.g. when saving favorites, currently selected preset
+/// or for associating preview files.
+///
+/// The schema is `<DATABASE_ID>|<INNER_PRESET_ID>`. The pipe character `|` can also be used within
+/// the inner preset ID, so in order to extract the database ID, it's important to split at the
+/// first pipe character and ignore the other ones. In general, it should be avoided to use
+/// the pipe character in the database ID or inner preset ID, but it's still important to escape it.
+///
+/// # Examples
+///
+/// - `defaults|vst2|1967946098`
+/// - `track-templates|Synths/Lead.RTrackTemplate`
+/// - `fx-chains|Synths/Sun.RfxChain`
+/// - `fx-presets|vst3-Surge XT.ini|My Preset`
+/// - `komplete|77c5507f5d0b421ea93eeb4cee4b6f99`
+/// - `n98h1f9unp92|maojiao/2023-02-03-ben/2023-02-03-ben.RPP|0FF9F738-7CF6-8A49-9AEA-A9AF26DF9C46`
+#[derive(Clone, Eq, PartialEq, Debug)]
+pub struct PersistentPresetId {
+    db_id: PersistentDatabaseId,
+    inner_preset_id: PersistentInnerPresetId,
+}
+
+impl PersistentPresetId {
+    pub fn new(db_id: PersistentDatabaseId, inner_preset_id: PersistentInnerPresetId) -> Self {
+        Self {
+            db_id,
+            inner_preset_id,
+        }
+    }
+}
+
+impl Display for PersistentPresetId {
+    fn fmt(&self, f: &mut Formatter) -> fmt::Result {
+        // Database IDs ideally shouldn't contain pipe characters, but if they do, we escaped them.
+        let escaped_db_id = PipeEscaped(self.db_id.get());
+        write!(f, "{escaped_db_id}|{}", self.inner_preset_id.get())
+    }
+}
+
+impl FromStr for PersistentPresetId {
+    type Err = &'static str;
+
+    fn from_str(s: &str) -> Result<Self, Self::Err> {
+        let (escaped_db_id, inner_preset_id) = s
+            .split_once(unescaped_pipe_pattern())
+            .ok_or("no | separator found in persistent preset ID")?;
+        // Unescaped pipe character (in the unlikely case that there was any)
+        let db_id = unescape_pipes(escaped_db_id);
+        let id = Self {
+            db_id: PersistentDatabaseId(db_id),
+            inner_preset_id: PersistentInnerPresetId(inner_preset_id.to_string()),
+        };
+        Ok(id)
+    }
+}
+
+pub fn unescaped_pipe_pattern() -> impl FnMut(char) -> bool {
+    unescaped_char_pattern('|')
+}
+
+/// A Rust string matching pattern that matches the given character, but only if it's not preceded
+/// by a backslash.
+fn unescaped_char_pattern(needle: char) -> impl FnMut(char) -> bool {
+    let mut prev_char = None;
+    move |c: char| {
+        let matches = if c == needle {
+            prev_char != Some('\\')
+        } else {
+            false
+        };
+        prev_char = Some(c);
+        matches
+    }
+}
+
+/// Converts "hello\|fellow" to "hello|fellow"
+pub fn unescape_pipes(escaped: &str) -> String {
+    escaped.replace(r"\|", "|")
+}
+
+pub struct PipeEscaped<'a>(pub &'a str);
+
+impl Display for PipeEscaped<'_> {
+    fn fmt(&self, f: &mut Formatter) -> fmt::Result {
+        for c in self.0.chars() {
+            if c == '|' {
+                f.write_str(r"\|")?;
+            } else {
+                f.write_char(c)?;
+            }
+        }
+        Ok(())
+    }
+}
+
+#[cfg(test)]
+mod tests {
+    use crate::{PersistentDatabaseId, PersistentInnerPresetId, PersistentPresetId};
+
+    #[test]
+    fn format_persistent_preset_id() {
+        let id = PersistentPresetId::new(
+            PersistentDatabaseId::new("test|hello".into()),
+            PersistentInnerPresetId::new("vst2|124135".into()),
+        );
+        assert_eq!(id.to_string(), r#"test\|hello|vst2|124135"#);
+    }
+
+    #[test]
+    fn parse_persistent_preset_id() {
+        let expression = r#"test\|hello|vst2|124135"#;
+        let parsed_id: PersistentPresetId = expression.parse().unwrap();
+        let expected_id = PersistentPresetId::new(
+            PersistentDatabaseId::new("test|hello".into()),
+            PersistentInnerPresetId::new("vst2|124135".into()),
+        );
+        assert_eq!(parsed_id, expected_id);
+    }
+}

plugin-reaper-relearn/pot/src/escape_catcher.rs

@@ -0,0 +1,65 @@
+use reaper_high::Reaper;
+use reaper_medium::{
+    AccelMsgKind, AcceleratorBehavior, AcceleratorKeyCode, AcceleratorPosition, RegistrationHandle,
+    TranslateAccel, TranslateAccelArgs, TranslateAccelResult,
+};
+use std::sync::atomic::{AtomicBool, Ordering};
+use std::sync::Arc;
+
+pub struct EscapeCatcher {
+    accel_handle: RegistrationHandle<EscapeCatcherAccel>,
+    escape_was_pressed: Arc<AtomicBool>,
+}
+
+impl TranslateAccel for EscapeCatcherAccel {
+    fn call(&mut self, args: TranslateAccelArgs) -> TranslateAccelResult {
+        let is_escape = args.msg.behavior().contains(AcceleratorBehavior::VirtKey)
+            && args.msg.message() == AccelMsgKind::KeyDown
+            && args.msg.key() == AcceleratorKeyCode::new(0x1b);
+        if !is_escape {
+            return TranslateAccelResult::NotOurWindow;
+        }
+        self.escape_was_pressed.store(true, Ordering::Relaxed);
+        TranslateAccelResult::Eat
+    }
+}
+
+struct EscapeCatcherAccel {
+    escape_was_pressed: Arc<AtomicBool>,
+}
+
+impl Default for EscapeCatcher {
+    fn default() -> Self {
+        Self::new()
+    }
+}
+
+impl EscapeCatcher {
+    pub fn new() -> Self {
+        let escape_was_pressed = Arc::new(AtomicBool::new(false));
+        let accel = EscapeCatcherAccel {
+            escape_was_pressed: escape_was_pressed.clone(),
+        };
+        let accel_handle = Reaper::get()
+            .medium_session()
+            .plugin_register_add_accelerator_register(Box::new(accel), AcceleratorPosition::Front)
+            .expect("couldn't register escape accelerator");
+        Self {
+            accel_handle,
+            escape_was_pressed,
+        }
+    }
+
+    pub fn escape_was_pressed(&self) -> bool {
+        self.escape_was_pressed.load(Ordering::Relaxed)
+    }
+}
+
+impl Drop for EscapeCatcher {
+    fn drop(&mut self) {
+        Reaper::get()
+            .medium_session()
+            .plugin_register_remove_accelerator(self.accel_handle)
+            .expect("escape accelerator was not registered");
+    }
+}

plugin-reaper-relearn/pot/src/nks.rs

@@ -0,0 +1,35 @@
+use base::default_util::{deserialize_null_default, is_default};
+
+#[derive(Clone, Eq, PartialEq, Debug, Default, serde::Serialize, serde::Deserialize)]
+pub struct PersistentNksFilterSettings {
+    #[serde(
+        default,
+        deserialize_with = "deserialize_null_default",
+        skip_serializing_if = "is_default"
+    )]
+    pub bank: Option<String>,
+    #[serde(
+        default,
+        deserialize_with = "deserialize_null_default",
+        skip_serializing_if = "is_default"
+    )]
+    pub sub_bank: Option<String>,
+    #[serde(
+        default,
+        deserialize_with = "deserialize_null_default",
+        skip_serializing_if = "is_default"
+    )]
+    pub category: Option<String>,
+    #[serde(
+        default,
+        deserialize_with = "deserialize_null_default",
+        skip_serializing_if = "is_default"
+    )]
+    pub sub_category: Option<String>,
+    #[serde(
+        default,
+        deserialize_with = "deserialize_null_default",
+        skip_serializing_if = "is_default"
+    )]
+    pub mode: Option<String>,
+}

plugin-reaper-relearn/pot/src/plugin_id.rs

@@ -0,0 +1,241 @@
+use base::LimitedAsciiString;
+use std::fmt;
+use std::fmt::{Display, Formatter};
+
+#[derive(Copy, Clone, Eq, PartialEq, Ord, PartialOrd, Hash, Debug)]
+pub enum PluginId {
+    Vst2 { vst_magic_number: i32 },
+    Vst3 { vst_uid: [u32; 4] },
+    Clap { clap_id: LimitedAsciiString<100> },
+    Js { js_id: LimitedAsciiString<100> },
+}
+
+impl PluginId {
+    pub fn vst2(vst_magic_number: i32) -> Self {
+        Self::Vst2 { vst_magic_number }
+    }
+
+    pub fn vst3(vst_uid: [u32; 4]) -> Self {
+        Self::Vst3 { vst_uid }
+    }
+
+    pub fn clap(id_expression: &str) -> Result<Self, &'static str> {
+        let id = Self::Clap {
+            clap_id: LimitedAsciiString::try_from_str(id_expression)?,
+        };
+        Ok(id)
+    }
+
+    pub fn js(id_expression: &str) -> Result<Self, &'static str> {
+        // It's better to normalize to lowercase. When loading the FX via TrackFX_AddByName,
+        // REAPER is case-insensitive anyway and we should be as well when doing comparisons.
+        let lowercase_id_expression = id_expression.to_lowercase();
+        let id = Self::Js {
+            js_id: LimitedAsciiString::try_from_str(&lowercase_id_expression)?,
+        };
+        Ok(id)
+    }
+
+    pub fn parse_from_rxml_line(line: &str) -> Result<PluginId, &'static str> {
+        let line = line.trim();
+        let mut tokens = splitty::split_unquoted_whitespace(line).unwrap_quotes(true);
+        let tag_opener = tokens.next().ok_or("missing FX tag opener")?;
+        match tag_opener {
+            "<VST" => {
+                // Examples:
+                // - <VST "VSTi: Zebra2 (u-he)" Zebra2.vst 0 Schmackes 1397572658<565354534D44327A6562726132000000> ""
+                // - <VST "VST3i: Pianoteq 8 (Modartt) (1->5ch)" "Pianoteq 8.vst3" 0 "" 1031062328{565354507438717069616E6F74657120} ""
+                // Skip plug-in name, file, zero, custom name
+                for _ in 0..4 {
+                    tokens.next();
+                }
+                // Process ID expression
+                let id_expression = tokens.next().ok_or("missing VST ID expression")?;
+                if let Some((_, remainder)) = id_expression.split_once('{') {
+                    // VST3
+                    let vst3_uid_string = remainder.strip_suffix('}').unwrap_or(remainder);
+                    let uid = parse_vst3_uid(vst3_uid_string)?;
+                    Ok(Self::vst3(uid))
+                } else if let Some((magic_number_string, _)) = id_expression.split_once('<') {
+                    // VST2
+                    let magic_number = parse_vst2_magic_number(magic_number_string)?;
+                    Ok(Self::vst2(magic_number))
+                } else {
+                    Err("couldn't process VST ID expression")
+                }
+            }
+            "<CLAP" => {
+                // Example: <CLAP "CLAPi: Surge XT (Surge Synth Team)" org.surge-synth-team.surge-xt Surgi
+                // Skip plug-in name
+                tokens.next();
+                // Process ID expression
+                let id_expression = tokens.next().ok_or("missing CLAP ID expression")?;
+                Self::clap(id_expression)
+            }
+            "<JS" => {
+                // Example: <JS analysis/hund ""
+                let id_expression = tokens.next().ok_or("missing JS ID expression")?;
+                Self::js(id_expression)
+            }
+            _ => Err("unknown FX tag opener"),
+        }
+    }
+
+    pub fn kind(&self) -> PluginKind {
+        match self {
+            PluginId::Vst2 { .. } => PluginKind::Vst2,
+            PluginId::Vst3 { .. } => PluginKind::Vst3,
+            PluginId::Clap { .. } => PluginKind::Clap,
+            PluginId::Js { .. } => PluginKind::Js,
+        }
+    }
+
+    pub fn content_formatted_for_reaper(&self) -> String {
+        PluginIdContentInReaperFormat(self).to_string()
+    }
+}
+
+/// Example: `1967946098` for a VST2 plug-in ID.
+pub struct PluginIdContentInReaperFormat<'a>(pub &'a PluginId);
+
+impl Display for PluginIdContentInReaperFormat<'_> {
+    fn fmt(&self, f: &mut Formatter) -> fmt::Result {
+        match self.0 {
+            PluginId::Clap { clap_id } => clap_id.fmt(f),
+            PluginId::Js { js_id } => js_id.fmt(f),
+            PluginId::Vst2 { vst_magic_number } => vst_magic_number.fmt(f),
+            PluginId::Vst3 { vst_uid } => {
+                // D39D5B69 D6AF42FA 12345678 534D4433
+                write!(
+                    f,
+                    "{:X}{:X}{:X}{:X}",
+                    vst_uid[0], vst_uid[1], vst_uid[2], vst_uid[3],
+                )
+            }
+        }
+    }
+}
+
+/// Example: `vst|1967946098` for a VST2 plug-in ID.
+pub struct PluginIdInPipeFormat<'a>(pub &'a PluginId);
+
+impl Display for PluginIdInPipeFormat<'_> {
+    fn fmt(&self, f: &mut Formatter) -> fmt::Result {
+        let kind = self.0.kind();
+        let kind = kind.as_ref();
+        let content = PluginIdContentInReaperFormat(self.0);
+        write!(f, "{kind}|{content}")
+    }
+}
+
+/// When adding a new variant, the serialization should correspond to the string which is used
+/// as prefix for the ini file names in "REAPER_RESOURCE_PATH/presets".
+#[derive(Copy, Clone, Eq, PartialEq, Debug, strum::AsRefStr, strum::EnumString)]
+pub enum PluginKind {
+    #[strum(serialize = "vst")]
+    Vst2,
+    #[strum(serialize = "vst3")]
+    Vst3,
+    #[strum(serialize = "clap")]
+    Clap,
+    #[strum(serialize = "js")]
+    Js,
+}
+
+impl PluginKind {
+    pub fn name(&self) -> &'static str {
+        match self {
+            Self::Vst2 => "VST",
+            Self::Vst3 => "VST3",
+            Self::Clap => "CLAP",
+            Self::Js => "JS",
+        }
+    }
+
+    /// Need to put some random string in front of "<" due to bug in REAPER < 6.69,
+    /// otherwise loading by VST2 magic number doesn't work.
+    pub fn reaper_add_by_name_prefix_fix(&self) -> &'static str {
+        match self {
+            Self::Vst2 | Self::Vst3 => "i7zh34z",
+            Self::Clap | Self::Js => "",
+        }
+    }
+
+    pub fn formatted_for_reaper(&self) -> &'static str {
+        match self {
+            Self::Vst2 => "<",
+            Self::Vst3 => "{",
+            Self::Clap | Self::Js => "",
+        }
+    }
+}
+
+/// "1397572658" => 1397572658
+pub fn parse_vst2_magic_number(expression: &str) -> Result<i32, &'static str> {
+    expression
+        .parse()
+        .map_err(|_| "couldn't parse VST2 magic number")
+}
+
+/// "565354507438717069616E6F74657120" => [0x56535450, 0x74387170, 0x69616E6F, 0x74657120]
+pub fn parse_vst3_uid(expression: &str) -> Result<[u32; 4], &'static str> {
+    fn parse_component(text: &str, i: usize) -> Result<u32, &'static str> {
+        let from = i * 8;
+        let until = from + 8;
+        let parsed = u32::from_str_radix(&text[from..until], 16)
+            .map_err(|_| "couldn't parse VST3 uid component")?;
+        Ok(parsed)
+    }
+    let uid = [
+        parse_component(expression, 0)?,
+        parse_component(expression, 1)?,
+        parse_component(expression, 2)?,
+        parse_component(expression, 3)?,
+    ];
+    Ok(uid)
+}
+
+#[cfg(test)]
+mod tests {
+    use crate::PluginId;
+
+    #[test]
+    pub fn vst2() {
+        assert_eq!(
+            PluginId::parse_from_rxml_line(
+                r#"<VST "VSTi: Zebra2 (u-he)" Zebra2.vst 0 Schmackes 1397572658<565354534D44327A6562726132000000> """#
+            ),
+            Ok(PluginId::vst2(1397572658))
+        );
+    }
+
+    #[test]
+    pub fn vst3() {
+        assert_eq!(
+            PluginId::parse_from_rxml_line(
+                r#"<VST "VST3i: Pianoteq 8 (Modartt) (1->5ch)" "Pianoteq 8.vst3" 0 "" 1031062328{565354507438717069616E6F74657120} """#
+            ),
+            Ok(PluginId::vst3([
+                0x56535450, 0x74387170, 0x69616E6F, 0x74657120
+            ]))
+        );
+    }
+
+    #[test]
+    pub fn clap() {
+        assert_eq!(
+            PluginId::parse_from_rxml_line(
+                r#"<CLAP "CLAPi: Surge XT (Surge Synth Team)" org.surge-synth-team.surge-xt Surgi"#
+            ),
+            Ok(PluginId::clap("org.surge-synth-team.surge-xt").unwrap())
+        );
+    }
+
+    #[test]
+    pub fn js() {
+        assert_eq!(
+            PluginId::parse_from_rxml_line(r#"<JS Analysis/hund """#),
+            Ok(PluginId::js("analysis/hund").unwrap())
+        );
+    }
+}

plugin-reaper-relearn/pot/src/plugins.rs

@@ -0,0 +1,720 @@
+use crate::{parse_vst2_magic_number, parse_vst3_uid, PluginId, ProductId};
+use base::file_util;
+use base::hash_util::NonCryptoHashMap;
+use camino::Utf8Path;
+use ini::Ini;
+use regex::Match;
+use std::fmt;
+use std::fmt::{Display, Formatter};
+use std::fs::File;
+use std::io::{BufRead, BufReader};
+use std::path::Path;
+use walkdir::WalkDir;
+
+#[derive(Clone, Debug, Default)]
+pub struct PluginDatabase {
+    plugins: NonCryptoHashMap<PluginId, Plugin>,
+    products: Vec<Product>,
+    detected_legacy_vst3_scan: bool,
+}
+
+/// Responsible for grouping similar plug-ins into products.
+#[derive(Default)]
+struct ProductAccumulator {
+    products: Vec<Product>,
+}
+
+impl ProductAccumulator {
+    /// Adds a product with the given characteristics.
+    pub fn add_other_product(&mut self, name: String, kind: Option<ProductKind>) -> ProductId {
+        let product = Product { name, kind };
+        self.products.push(product);
+        ProductId(self.products.len() as u32 - 1)
+    }
+
+    /// Tries to find an already added product matching the product name within the given plug-in
+    /// expression (and product kind) or creates a new product.
+    pub fn get_or_add_plugin_product(
+        &mut self,
+        name_expression: &str,
+        kind: Option<ProductKind>,
+    ) -> ProductId {
+        // Extract product name
+        let name = if let Some(name) = ProductName::parse(name_expression) {
+            normalize_product_main_name(name.main)
+        } else {
+            name_expression
+        };
+        // Find existing product
+        let existing_product = self
+            .products
+            .iter()
+            .enumerate()
+            .find(|(_, product)| product.name == name && product.kind == kind);
+        // Return existing or create new product
+        let i = match existing_product {
+            None => {
+                let new_product = Product {
+                    name: name.to_string(),
+                    kind,
+                };
+                self.products.push(new_product);
+                self.products.len() - 1
+            }
+            Some((i, _)) => i,
+        };
+        ProductId(i as u32)
+    }
+
+    pub fn into_products(self) -> Vec<Product> {
+        self.products
+    }
+}
+
+impl PluginDatabase {
+    pub fn crawl(reaper_resource_dir: &Utf8Path) -> Self {
+        let mut product_accumulator = ProductAccumulator::default();
+        let mut detected_legacy_vst3_scan = false;
+        let shared_library_plugins = crawl_shared_library_plugins(
+            &mut product_accumulator,
+            reaper_resource_dir,
+            &mut detected_legacy_vst3_scan,
+        );
+        let js_root_dir = reaper_resource_dir.join("Effects");
+        let js_plugins = crawl_js_plugins(&mut product_accumulator, &js_root_dir);
+        let plugin_map = shared_library_plugins
+            .into_iter()
+            .chain(js_plugins)
+            .map(|p| (p.common.core.id, p))
+            .collect();
+        Self {
+            plugins: plugin_map,
+            products: product_accumulator.into_products(),
+            detected_legacy_vst3_scan,
+        }
+    }
+
+    pub fn detected_legacy_vst3_scan(&self) -> bool {
+        self.detected_legacy_vst3_scan
+    }
+
+    pub fn plugins(&self) -> impl Iterator<Item = &Plugin> {
+        self.plugins.values()
+    }
+
+    pub fn products(&self) -> impl Iterator<Item = (ProductId, &Product)> {
+        self.products
+            .iter()
+            .enumerate()
+            .map(|(i, p)| (ProductId(i as _), p))
+    }
+
+    pub fn find_plugin_by_id(&self, plugin_id: &PluginId) -> Option<&Plugin> {
+        self.plugins.get(plugin_id)
+    }
+
+    pub fn find_product_by_id(&self, product_id: &ProductId) -> Option<&Product> {
+        self.products.get(product_id.0 as usize)
+    }
+
+    pub fn detect_plugin_from_rxml_line(&self, line: &str) -> Option<&Plugin> {
+        let is_fx_line = ["<VST ", "<CLAP ", "<JS "]
+            .into_iter()
+            .any(|suffix| line.starts_with(suffix));
+        if !is_fx_line {
+            return None;
+        }
+        let plugin_id = PluginId::parse_from_rxml_line(line).ok()?;
+        self.find_plugin_by_id(&plugin_id)
+    }
+}
+
+/// A product - an abstraction over related plug-ins.
+///
+/// Example: The product "Zebra2 (u-he)". This ignores architecture and plug-in framework.
+/// So this product stands for all of: "Zebra VSTi", "Zebra VST3i", "Zebra CLAPi",
+/// "Zebra VST (x86_64)", and so on.
+#[derive(Clone, Debug)]
+pub struct Product {
+    pub name: String,
+    pub kind: Option<ProductKind>,
+}
+
+#[derive(Clone, Debug)]
+pub struct Plugin {
+    /// Contains data relevant for all kinds of plug-ins.
+    pub common: PluginCommon,
+    /// Contains data specific to certain kinds of plug-ins.
+    pub kind: SuperPluginKind,
+}
+
+#[derive(Clone, Debug)]
+pub struct PluginCommon {
+    /// Full name of the plug-in without kind (for display purposes mainly).
+    ///
+    /// E.g. "Zebra2 (u-he)"
+    pub name: String,
+    pub core: PluginCore,
+}
+
+#[derive(Copy, Clone, Debug)]
+pub struct PluginCore {
+    /// Uniquely identifies the plug-in in a rather cheap way (copyable).
+    pub id: PluginId,
+    /// Whether we have an effect or an instrument or unknown.
+    pub product_kind: Option<ProductKind>,
+    /// What product this plug-in belongs to.
+    pub product_id: ProductId,
+}
+
+impl Display for PluginCommon {
+    fn fmt(&self, f: &mut Formatter) -> fmt::Result {
+        f.write_str(self.core.id.kind().name())?;
+        if let Some(ProductKind::Instrument) = self.core.product_kind {
+            f.write_str("i")?;
+        }
+        write!(f, ": {}", &self.name)?;
+        Ok(())
+    }
+}
+
+#[derive(Clone, Debug)]
+pub enum SuperPluginKind {
+    Vst(VstPlugin),
+    Clap(ClapPlugin),
+    Js(JsPlugin),
+}
+
+#[derive(Clone, Debug)]
+pub struct ClapPlugin {
+    /// Real file name, no characters replaced.
+    pub file_name: String,
+    /// According to Justin, this is a Win32 FILETIME timestamp (last write time and creation time,
+    /// concatenated).
+    pub filetime: String,
+    pub id: String,
+}
+
+#[derive(Clone, Debug)]
+pub struct JsPlugin {
+    /// Relative path from JS root dir.
+    ///
+    /// This is a runtime path and it's not normalized to lower-case! So it shouldn't be used
+    /// as an ID.
+    pub path: String,
+}
+
+#[derive(Clone, Debug)]
+pub struct VstPlugin {
+    /// Safe means: Each space and special character is replaced with an underscore.
+    pub safe_file_name: String,
+    /// A value which identifies the actual plug-in within a shell file.
+    ///
+    /// Some files are just shells. That means, they contain multiple actual plug-ins.
+    /// If this plug-in is part of a shell file, this value will be set. In practice, it's
+    /// equal to the magic number / uid_hash.
+    pub shell_qualifier: Option<String>,
+    pub checksum: String,
+    pub kind: VstPluginKind,
+}
+
+#[derive(Clone, Debug)]
+pub enum VstPluginKind {
+    Vst2 { magic_number: String },
+    Vst3 { uid_hash: String, uid: String },
+}
+
+impl VstPluginKind {
+    pub fn plugin_id(&self) -> Result<PluginId, &'static str> {
+        let id = match self {
+            VstPluginKind::Vst2 { magic_number } => PluginId::Vst2 {
+                vst_magic_number: parse_vst2_magic_number(magic_number)?,
+            },
+            VstPluginKind::Vst3 { uid, .. } => PluginId::Vst3 {
+                vst_uid: parse_vst3_uid(uid)?,
+            },
+        };
+        Ok(id)
+    }
+}
+
+#[derive(Copy, Clone, Eq, PartialEq, Hash, Debug, derive_more::Display)]
+pub enum ProductKind {
+    Effect,
+    Instrument,
+    Loop,
+    OneShot,
+}
+
+impl ProductKind {
+    pub fn komplete_id(&self) -> &'static u32 {
+        const INSTRUMENT: u32 = 1;
+        const EFFECT: u32 = 2;
+        const ONE_SHOT: u32 = 4;
+        const LOOP: u32 = 8;
+        use ProductKind as K;
+        match self {
+            K::Effect => &EFFECT,
+            K::Instrument => &INSTRUMENT,
+            K::Loop => &LOOP,
+            K::OneShot => &ONE_SHOT,
+        }
+    }
+}
+fn crawl_js_plugins(
+    product_accumulator: &mut ProductAccumulator,
+    js_root_dir: &Utf8Path,
+) -> Vec<Plugin> {
+    WalkDir::new(js_root_dir)
+        .follow_links(true)
+        .into_iter()
+        .filter_entry(|e| !file_util::is_hidden(e.file_name()))
+        .filter_map(|entry| {
+            let entry = entry.ok()?;
+            if !entry.file_type().is_file() {
+                return None;
+            }
+            let relative_path = entry.path().strip_prefix(js_root_dir).ok()?;
+            let relative_path = relative_path.to_str()?;
+            let product_kind = Some(ProductKind::Effect);
+            let js_desc = read_js_desc_from_file(entry.path())?;
+            let plugin = Plugin {
+                common: PluginCommon {
+                    name: js_desc.clone(),
+                    core: PluginCore {
+                        id: PluginId::js(relative_path).ok()?,
+                        product_kind,
+                        product_id: product_accumulator.add_other_product(js_desc, product_kind),
+                    },
+                },
+                kind: SuperPluginKind::Js(JsPlugin {
+                    path: relative_path.to_string(),
+                }),
+            };
+            Some(plugin)
+        })
+        .collect()
+}
+
+fn crawl_shared_library_plugins(
+    product_accumulator: &mut ProductAccumulator,
+    reaper_resource_dir: &Utf8Path,
+    detected_legacy_vst3_scan: &mut bool,
+) -> Vec<Plugin> {
+    WalkDir::new(reaper_resource_dir)
+        .max_depth(1)
+        .follow_links(false)
+        .into_iter()
+        .filter_map(|entry| {
+            let entry = entry.ok()?;
+            if !entry.file_type().is_file() {
+                return None;
+            }
+            let file_name = entry.file_name().to_str()?;
+            enum PlugType {
+                Vst,
+                Clap,
+            }
+            let plug_type = match file_name {
+                VST_CACHE_FILE => PlugType::Vst,
+                CLAP_CACHE_FILE => PlugType::Clap,
+                _ => return None,
+            };
+            let ini = Ini::load_from_file(entry.path()).ok()?;
+            let plugins = match plug_type {
+                PlugType::Vst => crawl_vst_plugins_in_ini_file(
+                    product_accumulator,
+                    ini,
+                    detected_legacy_vst3_scan,
+                ),
+                PlugType::Clap => crawl_clap_plugins_in_ini_file(product_accumulator, ini),
+            };
+            Some(plugins)
+        })
+        .flatten()
+        .collect()
+}
+
+fn crawl_clap_plugins_in_ini_file(
+    product_accumulator: &mut ProductAccumulator,
+    ini: Ini,
+) -> Vec<Plugin> {
+    ini.iter()
+        .filter_map(|(section, props)| {
+            let file_name = section?;
+            let checksum = props.get("_")?;
+            let plugins: Vec<_> = props
+                .iter()
+                .filter_map(|(key, value)| {
+                    if key == "_" {
+                        return None;
+                    }
+                    let (product_kind_id, plugin_name) = value.split_once('|')?;
+                    let product_kind = match product_kind_id {
+                        "0" => Some(ProductKind::Effect),
+                        "1" => Some(ProductKind::Instrument),
+                        _ => None,
+                    };
+                    let plugin = Plugin {
+                        common: PluginCommon {
+                            core: PluginCore {
+                                id: PluginId::clap(key).ok()?,
+                                product_kind,
+                                product_id: product_accumulator
+                                    .get_or_add_plugin_product(plugin_name, product_kind),
+                            },
+                            name: plugin_name.to_string(),
+                        },
+                        kind: SuperPluginKind::Clap(ClapPlugin {
+                            file_name: file_name.to_string(),
+                            filetime: checksum.to_string(),
+                            id: key.to_string(),
+                        }),
+                    };
+                    Some(plugin)
+                })
+                .collect();
+            Some(plugins)
+        })
+        .flatten()
+        .collect()
+}
+
+fn crawl_vst_plugins_in_ini_file(
+    product_accumulator: &mut ProductAccumulator,
+    ini: Ini,
+    detected_legacy_vst3_scan: &mut bool,
+) -> Vec<Plugin> {
+    let Some(section) = ini.section(Some("vstcache")) else {
+        return vec![];
+    };
+    section
+        .iter()
+        .filter_map(|(key, value)| {
+            let (safe_file_name, shell_qualifier) = match key.split_once('<') {
+                Some((first, second)) => (first.to_string(), Some(second.to_string())),
+                None => (key.to_string(), None),
+            };
+            let mut value_iter = value.splitn(3, ',');
+            let checksum = value_iter.next()?.to_string();
+            let plugin_id_expression = value_iter.next()?;
+            if plugin_id_expression == "0" {
+                // Must be a plug-in shell, not an actual plug-in.
+                return None;
+            }
+            let plugin_name_kind_expression = value_iter.next()?;
+            let vst_kind = match plugin_id_expression.split_once('{') {
+                None => {
+                    if safe_file_name.ends_with(".vst3") {
+                        // We skip VST3 plug-ins that have been scanned with old versions of
+                        // REAPER (and therefore missing a UID) in order to avoid creating wrong
+                        // persistent plug-in IDs).
+                        *detected_legacy_vst3_scan = true;
+                        return None;
+                    }
+                    VstPluginKind::Vst2 {
+                        magic_number: plugin_id_expression.to_string(),
+                    }
+                }
+                Some((left, right)) => VstPluginKind::Vst3 {
+                    uid_hash: left.to_string(),
+                    uid: right.to_string(),
+                },
+            };
+            let (name, product_kind) = match plugin_name_kind_expression.split_once("!!!") {
+                None => (
+                    plugin_name_kind_expression.to_string(),
+                    Some(ProductKind::Effect),
+                ),
+                Some((left, right)) => {
+                    let kind = match right {
+                        "VSTi" => Some(ProductKind::Instrument),
+                        _ => None,
+                    };
+                    (left.to_string(), kind)
+                }
+            };
+            let plugin = Plugin {
+                common: PluginCommon {
+                    core: PluginCore {
+                        id: vst_kind.plugin_id().ok()?,
+                        product_id: product_accumulator
+                            .get_or_add_plugin_product(name.as_str(), product_kind),
+                        product_kind,
+                    },
+                    name,
+                },
+                kind: SuperPluginKind::Vst(VstPlugin {
+                    safe_file_name,
+                    shell_qualifier,
+                    checksum,
+                    kind: vst_kind,
+                }),
+            };
+            Some(plugin)
+        })
+        .collect()
+}
+
+#[derive(Eq, PartialEq, Debug)]
+struct ProductName<'a> {
+    main: &'a str,
+    arch: Option<&'a str>,
+    company: &'a str,
+    channels: Option<&'a str>,
+}
+
+impl<'a> ProductName<'a> {
+    pub fn parse(name_expression: &'a str) -> Option<Self> {
+        let four_part_regex = base::regex!(r"(.*) \((.*)\) \((.*)\) \((.*)\)");
+        let three_part_regex = base::regex!(r"(.*) \((.*)\) \((.*)\)");
+        let two_part_regex = base::regex!(r"(.*) \((.*)\)");
+
+        if let Some(captures) = four_part_regex.captures(name_expression) {
+            return Some(ProductName {
+                main: s(captures.get(1)),
+                arch: Some(s(captures.get(2))),
+                company: s(captures.get(3)),
+                channels: Some(s(captures.get(4))),
+            });
+        }
+        if let Some(captures) = three_part_regex.captures(name_expression) {
+            let name = if &captures[2] == "x86_64" {
+                ProductName {
+                    main: s(captures.get(1)),
+                    arch: Some(s(captures.get(2))),
+                    company: s(captures.get(3)),
+                    channels: None,
+                }
+            } else {
+                ProductName {
+                    main: s(captures.get(1)),
+                    arch: None,
+                    company: s(captures.get(2)),
+                    channels: Some(s(captures.get(3))),
+                }
+            };
+            return Some(name);
+        }
+        if let Some(captures) = two_part_regex.captures(name_expression) {
+            return Some(ProductName {
+                main: s(captures.get(1)),
+                arch: None,
+                company: s(captures.get(2)),
+                channels: None,
+            });
+        }
+        None
+    }
+}
+
+fn s(m: Option<Match>) -> &str {
+    m.unwrap().as_str()
+}
+
+fn read_js_desc_from_file(path: &Path) -> Option<String> {
+    let file = File::open(path).ok()?;
+    let mut buffer = String::new();
+    let mut reader = BufReader::new(&file);
+    while let Ok(count) = reader.read_line(&mut buffer) {
+        if count == 0 {
+            // EOF
+            break;
+        }
+        let line = buffer.trim();
+        if let Some((left, right)) = line.split_once(':') {
+            if left == "desc" {
+                return Some(right.trim().to_string());
+            }
+        }
+        buffer.clear();
+    }
+    None
+}
+
+/// Further normalizes the already extracted main name so it conforms to the way "Komplete"
+/// displays the products.
+///
+/// # Maybe crop version number
+///
+/// Example: So we have successfully extracted "Kontakt 5" as main name from an expression
+/// "VSTi: Kontakt 5 (x86_64) (Native Instruments GmbH) (64 out). So far a very neutral extraction.
+/// But Komplete's product filter section doesn't distinguish between multiple versions of Kontakt.
+/// So we want to normalize this to just "Kontakt".
+///
+/// There are other NKS-ready products such as Pianoteq that distinguish between version numbers,
+/// so as a general rule we distinguish between version numbers and just add a few exceptions here.
+fn normalize_product_main_name(main_name: &str) -> &str {
+    maybe_crop_version_number(main_name)
+}
+
+fn maybe_crop_version_number(main_name: &str) -> &str {
+    const PRODUCT_NAMES_WITHOUT_VERSION_NUMBER: &[&str] =
+        &["Kontakt", "Absynth", "Guitar Rig", "Reaktor", "Battery"];
+    let Some((left, right)) = main_name.rsplit_once(' ') else {
+        // No right part
+        return main_name;
+    };
+    if PRODUCT_NAMES_WITHOUT_VERSION_NUMBER.contains(&left)
+        && right.chars().all(|c| c.is_ascii_digit())
+    {
+        // Conforms to pattern, e.g. "Kontakt 7"
+        left
+    } else {
+        // Doesn't conform to pattern
+        main_name
+    }
+}
+
+const VST_CACHE_FILE: &str = {
+    #[cfg(target_os = "windows")]
+    {
+        #[cfg(target_arch = "x86_64")]
+        {
+            "reaper-vstplugins64.ini"
+        }
+        #[cfg(target_arch = "x86")]
+        {
+            "reaper-vstplugins.ini"
+        }
+        #[cfg(target_arch = "arm64ec")]
+        {
+            "reaper-vstplugins64arwmin.ini"
+        }
+    }
+    #[cfg(target_os = "linux")]
+    {
+        #[cfg(target_arch = "x86_64")]
+        {
+            "reaper-vstplugins64.ini"
+        }
+        #[cfg(target_arch = "x86")]
+        {
+            "reaper-vstplugins.ini"
+        }
+        #[cfg(target_arch = "aarch64")]
+        {
+            "reaper-vstplugins_arm64.ini"
+        }
+        #[cfg(target_arch = "arm")]
+        {
+            "reaper-vstplugins.ini"
+        }
+    }
+    #[cfg(target_os = "macos")]
+    {
+        #[cfg(target_arch = "x86_64")]
+        {
+            "reaper-vstplugins64.ini"
+        }
+        #[cfg(target_arch = "aarch64")]
+        {
+            "reaper-vstplugins_arm64.ini"
+        }
+    }
+};
+
+const CLAP_CACHE_FILE: &str = {
+    #[cfg(target_os = "windows")]
+    {
+        #[cfg(target_arch = "x86_64")]
+        {
+            "reaper-clap-win64"
+        }
+        #[cfg(target_arch = "x86")]
+        {
+            "reaper-clap-win32"
+        }
+        #[cfg(target_arch = "arm64ec")]
+        {
+            "reaper-clap-winarm64"
+        }
+    }
+    #[cfg(target_os = "linux")]
+    {
+        #[cfg(target_arch = "x86_64")]
+        {
+            "reaper-clap-linux-x86_64"
+        }
+        #[cfg(target_arch = "x86")]
+        {
+            "reaper-clap-linux-i386"
+        }
+        #[cfg(target_arch = "aarch64")]
+        {
+            "reaper-clap-linux-aarch64"
+        }
+        #[cfg(target_arch = "arm")]
+        {
+            "reaper-clap-linux-arm"
+        }
+    }
+    #[cfg(target_os = "macos")]
+    {
+        #[cfg(target_arch = "x86_64")]
+        {
+            "reaper-clap-macos-x86_64"
+        }
+        #[cfg(target_arch = "aarch64")]
+        {
+            "reaper-clap-macos-aarch64.ini"
+        }
+    }
+};
+
+#[cfg(test)]
+mod tests {
+    use crate::plugins::ProductName;
+
+    #[test]
+    pub fn product_name_parsing_2() {
+        assert_eq!(
+            ProductName::parse("TDR Nova (Tokyo Dawn Labs)"),
+            Some(ProductName {
+                main: "TDR Nova",
+                arch: None,
+                company: "Tokyo Dawn Labs",
+                channels: None,
+            })
+        );
+    }
+
+    #[test]
+    pub fn product_name_parsing_3_arch() {
+        assert_eq!(
+            ProductName::parse("VC 76 (x86_64) (Native Instruments GmbH)"),
+            Some(ProductName {
+                main: "VC 76",
+                arch: Some("x86_64"),
+                company: "Native Instruments GmbH",
+                channels: None,
+            })
+        );
+    }
+
+    #[test]
+    pub fn product_name_parsing_3_ch() {
+        assert_eq!(
+            ProductName::parse("Surge XT (Surge Synth Team) (2->6ch)"),
+            Some(ProductName {
+                main: "Surge XT",
+                arch: None,
+                company: "Surge Synth Team",
+                channels: Some("2->6ch"),
+            })
+        );
+    }
+
+    #[test]
+    pub fn product_name_parsing_4() {
+        assert_eq!(
+            ProductName::parse("Sitala (x86_64) (Decomposer) (32 out)"),
+            Some(ProductName {
+                main: "Sitala",
+                arch: Some("x86_64"),
+                company: "Decomposer",
+                channels: Some("32 out"),
+            })
+        );
+    }
+}

plugin-reaper-relearn/pot/src/pot_database.rs

@@ -0,0 +1,554 @@
+use crate::provider_database::{
+    Database, DatabaseId, InnerFilterItem, ProviderContext, SortablePresetId,
+    FIL_HAS_PREVIEW_FALSE, FIL_HAS_PREVIEW_TRUE, FIL_IS_AVAILABLE_FALSE, FIL_IS_AVAILABLE_TRUE,
+    FIL_IS_FAVORITE_FALSE, FIL_IS_FAVORITE_TRUE, FIL_IS_SUPPORTED_FALSE, FIL_IS_SUPPORTED_TRUE,
+    FIL_IS_USER_PRESET_FALSE, FIL_IS_USER_PRESET_TRUE, FIL_PRODUCT_KIND_EFFECT,
+    FIL_PRODUCT_KIND_INSTRUMENT, FIL_PRODUCT_KIND_LOOP, FIL_PRODUCT_KIND_ONE_SHOT,
+};
+use crate::providers::directory::{DirectoryDatabase, DirectoryDbConfig};
+use crate::providers::komplete::KompleteDatabase;
+use crate::{
+    preview_exists, BuildInput, Fil, FilterItem, FilterItemCollections, FilterItemId, Filters,
+    InnerBuildInput, PersistentDatabaseId, PersistentPresetId, PluginId, PotFavorites, PotPreset,
+    PresetId, PresetWithId, Stats,
+};
+use base::{blocking_read_lock, blocking_write_lock};
+
+use crate::plugins::PluginDatabase;
+use crate::providers::defaults::DefaultsDatabase;
+use crate::providers::ini::IniDatabase;
+
+use enumset::{enum_set, EnumSet};
+use helgobox_api::persistence::PotFilterKind;
+use reaper_high::Reaper;
+use std::collections::{BTreeMap, HashSet};
+use std::error::Error;
+use std::fmt::Debug;
+use std::ops::Deref;
+
+use base::hash_util::NonCryptoIndexSet;
+use std::sync::atomic::{AtomicBool, AtomicU8, Ordering};
+use std::sync::{RwLock, RwLockReadGuard};
+use std::time::{Duration, Instant};
+
+pub fn pot_db() -> &'static PotDatabase {
+    use once_cell::sync::Lazy;
+    static POT_DB: Lazy<PotDatabase> = Lazy::new(PotDatabase::open);
+    &POT_DB
+}
+
+type BoxedDatabase = Box<dyn Database + Send + Sync>;
+type DatabaseOpeningResult = Result<BoxedDatabase, PotDatabaseError>;
+
+// The pot database is thread-safe! We achieve this by using internal read-write locks. Making it
+// thread-safe greatly simplifies usage of PotDatabase from a consumer perspective, because we can
+// easily obtain a static reference to it and let the pot database internals decide how to deal with
+// concurrency.
+//
+// But not just that, we can also improve performance. If the pot database wouldn't be thread-safe,
+// we would have to expose it wrapped by a mutex or read-write lock - which means less fine-granular
+// locking. Either the whole thing is locked or not at all.
+//
+// By having the RwLocks around the provider databases and not around the database collection, we
+// can have "more" concurrent access. E.g. find_preset_by_id, a function which can be called very
+// often by the GUI, only read-locks one particular database, not all. So if another database
+// is currently written to, it doesn't matter. It's just more flexible. Also, in future we might
+// want to use some fork-join approach to refresh/search concurrently multiple databases.
+// This would require having a RwLock around the database itself
+// because we would need to pass the database reference to the async code with an Arc, but an Arc
+// alone doesn't allow mutation of its contents. That's true even if the async database access would
+// be read-only. The synchronous refresh would still need mutable access but we wouldn't be able to
+// get one directly within an Arc.
+pub struct PotDatabase {
+    plugin_db: RwLock<PluginDatabase>,
+    databases: RwLock<Databases>,
+    revision: AtomicU8,
+    detected_legacy_vst3_scan: AtomicBool,
+}
+
+type Databases = BTreeMap<DatabaseId, RwLock<BoxedDatabase>>;
+
+#[derive(Clone, Debug, derive_more::Display)]
+pub struct PotDatabaseError(String);
+
+impl Error for PotDatabaseError {}
+
+fn box_db_result<D: Database + Send + Sync + 'static>(
+    opening_result: Result<D, Box<dyn Error>>,
+) -> DatabaseOpeningResult {
+    let db = opening_result.map_err(|e| PotDatabaseError(e.to_string()))?;
+    Ok(Box::new(db))
+}
+
+impl PotDatabase {
+    pub fn open() -> Self {
+        let resource_path = Reaper::get().resource_path();
+        let komplete_db = KompleteDatabase::open();
+        let rfx_chain_db = {
+            let config = DirectoryDbConfig {
+                persistent_id: PersistentDatabaseId::new("fx-chains".to_string()),
+                root_dir: resource_path.join("FXChains"),
+                valid_extensions: &["RfxChain"],
+                name: "FX chains",
+                description: "All the RfxChain files in your FXChains directory",
+            };
+            DirectoryDatabase::open(config)
+        };
+        let track_template_db = {
+            let config = DirectoryDbConfig {
+                persistent_id: PersistentDatabaseId::new("track-templates".to_string()),
+                root_dir: resource_path.join("TrackTemplates"),
+                valid_extensions: &["RTrackTemplate"],
+                name: "Track templates",
+                description: "All the RTrackTemplate files in your TrackTemplates directory.\n\
+                Doesn't load the complete track, only its FX chain!",
+            };
+            DirectoryDatabase::open(config)
+        };
+        let ini_db = IniDatabase::open(
+            PersistentDatabaseId::new("fx-presets".to_string()),
+            resource_path.join("presets"),
+        );
+        let defaults_db = DefaultsDatabase::open();
+        let databases = [
+            box_db_result(komplete_db),
+            box_db_result(rfx_chain_db),
+            box_db_result(track_template_db),
+            box_db_result(ini_db),
+            box_db_result(Ok(defaults_db)),
+        ];
+        let databases = databases
+            .into_iter()
+            .flatten()
+            .enumerate()
+            .map(|(i, db)| (DatabaseId(i as _), RwLock::new(db)))
+            .collect();
+        Self {
+            plugin_db: Default::default(),
+            databases: RwLock::new(databases),
+            revision: Default::default(),
+            detected_legacy_vst3_scan: Default::default(),
+        }
+    }
+
+    /// Returns a number that will be increased with each database refresh.
+    pub fn revision(&self) -> u8 {
+        self.revision.load(Ordering::Relaxed)
+    }
+
+    pub fn refresh(&self) {
+        // Build provider context
+        let resource_path = Reaper::get().resource_path();
+        // Crawl plug-ins
+        let plugin_db = PluginDatabase::crawl(&resource_path);
+        // In order to be able to query the legacy-vst3-scan result without having to lock the
+        // plug-in DB (which could lead to unresponsive UI), we save it as atomic bool right here.
+        self.detected_legacy_vst3_scan
+            .store(plugin_db.detected_legacy_vst3_scan(), Ordering::Relaxed);
+        let provider_context = ProviderContext::new(&plugin_db);
+        // Refresh databases
+        for db in self.read_lock_databases().values() {
+            let mut db = blocking_write_lock(db, "pot db refresh provider db");
+            let _ = db.refresh(&provider_context);
+        }
+        // Memorize plug-ins
+        *blocking_write_lock(&self.plugin_db, "pot db refresh plugin db") = plugin_db;
+        // Increment revision
+        self.revision.fetch_add(1, Ordering::Relaxed);
+    }
+
+    pub fn detected_legacy_vst3_scan(&self) -> bool {
+        self.detected_legacy_vst3_scan.load(Ordering::Relaxed)
+    }
+
+    fn read_lock_databases(&self) -> RwLockReadGuard<Databases> {
+        blocking_read_lock(&self.databases, "read-lock pot-db databases")
+    }
+
+    fn read_lock_plugin_db(&self) -> RwLockReadGuard<PluginDatabase> {
+        blocking_read_lock(&self.plugin_db, "read-lock plug-in database")
+    }
+
+    pub fn add_database(&self, db: impl Database + Send + Sync + 'static) -> DatabaseId {
+        let mut databases = blocking_write_lock(&self.databases, "add_database");
+        let new_db_id = DatabaseId(databases.len() as u32);
+        databases.insert(new_db_id, RwLock::new(Box::new(db)));
+        new_db_id
+    }
+
+    pub fn build_collections(
+        &self,
+        mut input: BuildInput,
+        affected_kinds: EnumSet<PotFilterKind>,
+    ) -> BuildOutput {
+        // Preparation
+        // TODO-high-pot Implement correctly as soon as favorites writable
+        let favorites = PotFavorites::default();
+        let plugin_db = self.read_lock_plugin_db();
+        let provider_context = ProviderContext::new(&plugin_db);
+        // Build constant filter collections
+        let mut total_output = BuildOutput {
+            supported_filter_kinds: enum_set!(
+                PotFilterKind::Database
+                    | PotFilterKind::IsUser
+                    | PotFilterKind::IsFavorite
+                    | PotFilterKind::ProductKind
+            ),
+            ..Default::default()
+        };
+        measure_duration(&mut total_output.stats.filter_query_duration, || {
+            add_constant_filter_items(affected_kinds, &mut total_output.filter_item_collections);
+            // Let all databases build filter collections and accumulate them
+            let mut database_filter_items = Vec::new();
+            let mut used_product_ids = HashSet::new();
+            for (db_id, db) in self.read_lock_databases().deref() {
+                // If the database is on the exclude list, we don't even want it to appear in the
+                // database list.
+                if input.filter_excludes.contains_database(*db_id) {
+                    continue;
+                }
+                // Acquire database access
+                let db = blocking_read_lock(db, "pot db build_collections 1");
+                // Create database filter item
+                let filter_item = FilterItem {
+                    persistent_id: "".to_string(),
+                    id: FilterItemId(Some(Fil::Database(*db_id))),
+                    parent_name: None,
+                    name: Some(db.name().to_string()),
+                    icon: None,
+                    more_info: Some(db.description().to_string()),
+                };
+                database_filter_items.push(filter_item);
+                // Don't continue if database doesn't match filter
+                // (but it should appear on the list)
+                if !input.filters.database_matches(*db_id) {
+                    continue;
+                }
+                // Add supported filter kinds
+                total_output.supported_filter_kinds |= db.supported_advanced_filter_kinds();
+                // Build and accumulate filters collections
+                let inner_input = InnerBuildInput::new(&input, &favorites, *db_id);
+                let Ok(filter_collections) =
+                    db.query_filter_collections(&provider_context, inner_input, affected_kinds)
+                else {
+                    continue;
+                };
+                // Add unique filter items directly to the list of filters. Gather shared filter
+                // items so we can deduplicate them later.
+                for (kind, items) in filter_collections.into_iter() {
+                    let final_filter_items = items.into_iter().filter_map(|i| match i {
+                        InnerFilterItem::Unique(i) => Some(i),
+                        InnerFilterItem::Product(pid) => {
+                            used_product_ids.insert(pid);
+                            None
+                        }
+                    });
+                    total_output
+                        .filter_item_collections
+                        .extend(kind, final_filter_items);
+                }
+            }
+            // Process shared filter items
+            let product_filter_items = used_product_ids.into_iter().filter_map(|pid| {
+                let product = plugin_db.find_product_by_id(&pid)?;
+                let filter_item = FilterItem {
+                    persistent_id: "".to_string(),
+                    id: FilterItemId(Some(Fil::Product(pid))),
+                    parent_name: None,
+                    name: Some(product.name.clone()),
+                    icon: None,
+                    more_info: product.kind.map(|k| k.to_string()),
+                };
+                Some(filter_item)
+            });
+            total_output
+                .filter_item_collections
+                .extend(PotFilterKind::Bank, product_filter_items);
+            // Add database filter items
+            if affected_kinds.contains(PotFilterKind::Database) {
+                total_output
+                    .filter_item_collections
+                    .set(PotFilterKind::Database, database_filter_items);
+            }
+            // Important: At this point, some previously selected filters might not exist anymore.
+            // So we should reset them and not let them influence the preset query anymore!
+            input.filters.clear_if_not_available_anymore(
+                affected_kinds,
+                &total_output.filter_item_collections,
+            );
+        });
+        // Finally build
+        let mut sortable_preset_ids: Vec<_> =
+            measure_duration(&mut total_output.stats.preset_query_duration, || {
+                self.gather_preset_ids_internal(&input, &provider_context, &favorites)
+            });
+        // Apply "has preview" filter if necessary (expensive!)
+        measure_duration(&mut total_output.stats.preview_filter_duration, || {
+            self.apply_has_preview_filter(&input.filters, &mut sortable_preset_ids);
+        });
+        // Sort filter items and presets
+        measure_duration(&mut total_output.stats.sort_duration, || {
+            for (kind, collection) in total_output.filter_item_collections.iter_mut() {
+                if kind.wants_sorting() {
+                    collection.sort_by(|i1, i2| {
+                        lexical_sort::lexical_cmp(i1.sort_name(), i2.sort_name())
+                    });
+                }
+            }
+            sortable_preset_ids.sort_by(|(_, p1), (_, p2)| {
+                lexical_sort::lexical_cmp(&p1.preset_name, &p2.preset_name)
+            });
+        });
+        // Index presets. Because later, we look up the preset index by the preset ID and vice versa
+        // and we want that to happen without complexity O(n)! There can be tons of presets!
+        measure_duration(&mut total_output.stats.index_duration, || {
+            total_output.preset_collection = sortable_preset_ids
+                .into_iter()
+                .map(|(db_id, p)| PresetId::new(db_id, p.inner_preset_id))
+                .collect();
+        });
+        total_output
+    }
+
+    fn apply_has_preview_filter(
+        &self,
+        filters: &Filters,
+        sortable_preset_ids: &mut Vec<(DatabaseId, SortablePresetId)>,
+    ) {
+        if let Some(wants_preview) = filters.wants_preview() {
+            let reaper_resource_dir = Reaper::get().resource_path();
+            sortable_preset_ids.retain(|(db_id, sortable_preset_id)| {
+                let preset_id = PresetId::new(*db_id, sortable_preset_id.inner_preset_id);
+                if let Some(preset) = self.find_preset_by_id(preset_id) {
+                    preview_exists(&preset, &reaper_resource_dir) == wants_preview
+                } else {
+                    // Preset doesn't exist? Shouldn't happen, but treat it like a missing preview.
+                    !wants_preview
+                }
+            });
+        }
+    }
+
+    /// Gathers an unsorted list of preset respecting all pre-filters.
+    pub fn gather_presets(&self, input: BuildInput) -> Vec<PresetWithId> {
+        // TODO-high-pot Implement correctly as soon as favorites writable
+        let favorites = PotFavorites::default();
+        let plugin_db = self.read_lock_plugin_db();
+        let provider_context = ProviderContext::new(&plugin_db);
+        self.gather_preset_ids_internal(&input, &provider_context, &favorites)
+            .into_iter()
+            .filter_map(|(db_id, sortable_preset_id)| {
+                let preset_id = PresetId::new(db_id, sortable_preset_id.inner_preset_id);
+                let preset = self.find_preset_by_id(preset_id)?;
+                Some(PresetWithId::new(preset_id, preset))
+            })
+            .collect()
+    }
+
+    fn gather_preset_ids_internal(
+        &self,
+        input: &BuildInput,
+        provider_context: &ProviderContext,
+        favorites: &PotFavorites,
+    ) -> Vec<(DatabaseId, SortablePresetId)> {
+        self.read_lock_databases()
+            .deref()
+            .iter()
+            .filter(|(db_id, _)| {
+                input.filters.database_matches(**db_id)
+                    && !input.filter_excludes.contains_database(**db_id)
+            })
+            .filter_map(|(db_id, db)| {
+                // Acquire database access
+                let db = blocking_read_lock(db, "pot db build_collections 2");
+                // Don't even try to get presets if one filter is set which is not
+                // supported by database.
+                if input
+                    .filters
+                    .any_unsupported_filter_is_set_to_concrete_value(
+                        db.supported_advanced_filter_kinds(),
+                    )
+                {
+                    return None;
+                }
+                // Let database build presets
+                let inner_input = InnerBuildInput::new(input, favorites, *db_id);
+                let preset_ids = db.query_presets(provider_context, inner_input).ok()?;
+                Some((*db_id, preset_ids))
+            })
+            .flat_map(|(db_id, preset_ids)| preset_ids.into_iter().map(move |p| (db_id, p)))
+            .collect()
+    }
+
+    pub fn find_preset_by_id(&self, preset_id: PresetId) -> Option<PotPreset> {
+        let plugin_db = self.read_lock_plugin_db();
+        let provider_context = ProviderContext::new(&plugin_db);
+        let databases = self.read_lock_databases();
+        let db = databases.get(&preset_id.database_id)?;
+        let db = blocking_read_lock(db, "pot db find_preset_by_id 1");
+        db.find_preset_by_id(&provider_context, preset_id.preset_id)
+    }
+
+    pub fn with_plugin_db<R>(&self, f: impl FnOnce(&PluginDatabase) -> R) -> R {
+        f(&self.read_lock_plugin_db())
+    }
+
+    pub fn try_with_db<R>(
+        &self,
+        db_id: DatabaseId,
+        f: impl FnOnce(&dyn Database) -> R,
+    ) -> Result<R, &'static str> {
+        let databases = self.read_lock_databases();
+        let db = databases.get(&db_id).ok_or("database not found")?;
+        let db = db
+            .try_read()
+            .map_err(|_| "couldn't acquire provider db lock")?;
+        let r = f(&**db);
+        Ok(r)
+    }
+
+    pub fn try_find_preset_by_id(
+        &self,
+        preset_id: PresetId,
+    ) -> Result<Option<PotPreset>, &'static str> {
+        let plugin_db = self
+            .plugin_db
+            .try_read()
+            .map_err(|_| "couldn't acquire plugin db lock")?;
+        let provider_context = ProviderContext::new(&plugin_db);
+        let databases = self.read_lock_databases();
+        let db = databases
+            .get(&preset_id.database_id)
+            .ok_or("database not found")?;
+        let db = db
+            .try_read()
+            .map_err(|_| "couldn't acquire provider db lock")?;
+        Ok(db.find_preset_by_id(&provider_context, preset_id.preset_id))
+    }
+
+    /// Ignores exclude lists.
+    pub fn find_unsupported_preset_matching(
+        &self,
+        plugin_id: &PluginId,
+        preset_name: &str,
+    ) -> Option<PersistentPresetId> {
+        let product_id = {
+            let plugin_db = self.read_lock_plugin_db();
+            let plugin = plugin_db.find_plugin_by_id(plugin_id)?;
+            plugin.common.core.product_id
+        };
+        self.read_lock_databases().values().find_map(|db| {
+            // Acquire database access
+            let db = blocking_read_lock(db, "pot db find_unsupported_preset_matching");
+            // Find preset
+            let preset = db.find_unsupported_preset_matching(product_id, preset_name)?;
+            Some(preset.common.persistent_id)
+        })
+    }
+}
+
+#[derive(Default)]
+pub struct BuildOutput {
+    pub supported_filter_kinds: EnumSet<PotFilterKind>,
+    pub filter_item_collections: FilterItemCollections,
+    pub preset_collection: NonCryptoIndexSet<PresetId>,
+    pub stats: Stats,
+}
+
+fn measure_duration<R>(duration: &mut Duration, f: impl FnOnce() -> R) -> R {
+    let start = Instant::now();
+    let r = f();
+    *duration = start.elapsed();
+    r
+}
+
+fn add_constant_filter_items(
+    affected_kinds: EnumSet<PotFilterKind>,
+    filter_item_collections: &mut FilterItemCollections,
+) {
+    if affected_kinds.contains(PotFilterKind::IsAvailable) {
+        filter_item_collections.set(
+            PotFilterKind::IsAvailable,
+            create_filter_items_is_available(),
+        );
+    }
+    if affected_kinds.contains(PotFilterKind::IsSupported) {
+        filter_item_collections.set(
+            PotFilterKind::IsSupported,
+            create_filter_items_is_supported(),
+        );
+    }
+    if affected_kinds.contains(PotFilterKind::IsFavorite) {
+        filter_item_collections.set(PotFilterKind::IsFavorite, create_filter_items_is_favorite());
+    }
+    if affected_kinds.contains(PotFilterKind::IsUser) {
+        filter_item_collections.set(PotFilterKind::IsUser, create_filter_items_is_user());
+    }
+    if affected_kinds.contains(PotFilterKind::HasPreview) {
+        filter_item_collections.set(PotFilterKind::HasPreview, create_filter_items_has_preview());
+    }
+    if affected_kinds.contains(PotFilterKind::ProductKind) {
+        filter_item_collections.set(
+            PotFilterKind::ProductKind,
+            create_filter_items_product_kind(),
+        );
+    }
+}
+
+fn create_filter_items_is_available() -> Vec<FilterItem> {
+    vec![
+        FilterItem::simple(FIL_IS_AVAILABLE_FALSE, "Not available", '❌', ""),
+        FilterItem::simple(
+            FIL_IS_AVAILABLE_TRUE,
+            "Available",
+            '✔',
+            "Usually means that the \
+        corresponding plug-in has been scanned before by REAPER.\n\
+        For Komplete, it means that the preset file itself is available.",
+        ),
+    ]
+}
+
+fn create_filter_items_is_supported() -> Vec<FilterItem> {
+    vec![
+        FilterItem::simple(FIL_IS_SUPPORTED_FALSE, "Not supported", '☹', ""),
+        FilterItem::simple(
+            FIL_IS_SUPPORTED_TRUE,
+            "Supported",
+            '☺',
+            "Means that Pot Browser \
+        can automatically load the preset into the corresponding plug-in.",
+        ),
+    ]
+}
+
+fn create_filter_items_is_favorite() -> Vec<FilterItem> {
+    vec![
+        FilterItem::simple(FIL_IS_FAVORITE_FALSE, "Not favorite", '☆', ""),
+        FilterItem::simple(FIL_IS_FAVORITE_TRUE, "Favorite", '★', ""),
+    ]
+}
+
+fn create_filter_items_product_kind() -> Vec<FilterItem> {
+    vec![
+        FilterItem::none(),
+        FilterItem::simple(FIL_PRODUCT_KIND_INSTRUMENT, "Instrument", '🎹', ""),
+        FilterItem::simple(FIL_PRODUCT_KIND_EFFECT, "Effect", '✨', ""),
+        FilterItem::simple(FIL_PRODUCT_KIND_LOOP, "Loop", '➿', ""),
+        FilterItem::simple(FIL_PRODUCT_KIND_ONE_SHOT, "One shot", '💥', ""),
+    ]
+}
+
+fn create_filter_items_is_user() -> Vec<FilterItem> {
+    vec![
+        FilterItem::simple(FIL_IS_USER_PRESET_FALSE, "Factory preset", '🏭', ""),
+        FilterItem::simple(FIL_IS_USER_PRESET_TRUE, "User preset", '🕵', ""),
+    ]
+}
+
+fn create_filter_items_has_preview() -> Vec<FilterItem> {
+    vec![
+        FilterItem::simple(FIL_HAS_PREVIEW_FALSE, "No preview", '🔇', "Display only presets that have no preview. This filter can take very long when operating on a large preset list because it checks whether the preview files actually exist!"),
+        FilterItem::simple(FIL_HAS_PREVIEW_TRUE, "Has preview", '🔊', "Display only presets that have a preview. This filter can take very long when operating on a large preset list because it checks whether the preview files actually exist!"),
+    ]
+}

plugin-reaper-relearn/pot/src/preset_crawler.rs

@@ -0,0 +1,393 @@
+use crate::{
+    parse_vst2_magic_number, parse_vst3_uid, pot_db, EscapeCatcher, PersistentPresetId, PluginId,
+};
+use base::enigo::EnigoMouse;
+use base::future_util::millis;
+use base::hash_util::NonCryptoIndexMap;
+use base::{blocking_lock_arc, file_util, hash_util};
+use base::{Mouse, MouseCursorPosition};
+use camino::{Utf8Path, Utf8PathBuf};
+use helgobox_api::persistence::MouseButton;
+use reaper_high::{Fx, FxInfo, Reaper};
+use std::error::Error;
+use std::fs;
+use std::fs::File;
+use std::io::{Read, Seek, SeekFrom, Write};
+use std::sync::{Arc, Mutex};
+
+pub type SharedPresetCrawlingState = Arc<Mutex<PresetCrawlingState>>;
+
+#[derive(Debug)]
+pub struct PresetCrawlingState {
+    crawled_presets: NonCryptoIndexMap<String, CrawledPreset>,
+    duplicate_preset_names: Vec<String>,
+    same_preset_name_in_a_row: Option<String>,
+    same_preset_name_in_a_row_attempts: u32,
+    same_preset_names_like_beginning: Vec<String>,
+    same_preset_name_like_beginning_attempts: u32,
+    total_bytes_crawled: usize,
+}
+
+#[derive(Debug)]
+pub struct PresetCrawlingOutcome {
+    /// One temporary file that holds the chunks of all FXs when crawling finished.
+    /// Will be copied to separate destination files at a later stage.
+    /// If not set when stopped, this means at first it's a failure. Later we take the
+    /// file out of here for processing, in that case it's also `None`.
+    pub chunks_file: File,
+    pub reason: PresetCrawlerStopReason,
+}
+
+impl PresetCrawlingOutcome {
+    pub fn new(chunks_file: File, reason: PresetCrawlerStopReason) -> Self {
+        Self {
+            chunks_file,
+            reason,
+        }
+    }
+}
+
+impl PresetCrawlingState {
+    pub fn new() -> SharedPresetCrawlingState {
+        let state = Self {
+            crawled_presets: Default::default(),
+            duplicate_preset_names: Default::default(),
+            same_preset_name_in_a_row: None,
+            same_preset_name_in_a_row_attempts: 0,
+            same_preset_names_like_beginning: Default::default(),
+            same_preset_name_like_beginning_attempts: 0,
+            total_bytes_crawled: 0,
+        };
+        Arc::new(Mutex::new(state))
+    }
+
+    pub fn last_crawled_preset(&self) -> Option<&CrawledPreset> {
+        let last = self.crawled_presets.last()?;
+        Some(last.1)
+    }
+
+    pub fn pop_crawled_preset(&mut self) -> Option<CrawledPreset> {
+        let last = self.crawled_presets.pop()?;
+        Some(last.1)
+    }
+
+    pub fn bytes_crawled(&self) -> usize {
+        self.total_bytes_crawled
+    }
+
+    pub fn crawled_presets(&self) -> &NonCryptoIndexMap<String, CrawledPreset> {
+        &self.crawled_presets
+    }
+
+    pub fn preset_count(&self) -> u32 {
+        self.crawled_presets.len() as _
+    }
+
+    pub fn duplicate_preset_name_count(&self) -> u32 {
+        self.duplicate_preset_names.len() as _
+    }
+
+    pub fn duplicate_preset_names(&self) -> &[String] {
+        &self.duplicate_preset_names
+    }
+
+    fn add_preset(&mut self, preset: CrawledPreset, never_stop_crawling: bool) -> NextCrawlStep {
+        // Give stop signal if we reached the end of the list or are at its beginning again.
+        if !never_stop_crawling {
+            if let Some(step) = self.make_stop_check(&preset) {
+                return step;
+            }
+        }
+        // Reset "same preset name attempts" logic
+        self.same_preset_name_in_a_row_attempts = 0;
+        if let Some(last_same_preset_name) = self.same_preset_name_in_a_row.take() {
+            // Turns out that the last discovered same preset name was actually not the end
+            // of the preset list but just an intermediate duplicate. Treat it as such!
+            self.duplicate_preset_names.push(last_same_preset_name);
+        }
+        // Reset "same preset name like beginning" logic
+        self.same_preset_name_like_beginning_attempts = 0;
+        self.duplicate_preset_names
+            .append(&mut self.same_preset_names_like_beginning);
+        // Add or skip
+        if self.crawled_presets.contains_key(&preset.name) {
+            // Duplicate name. Skip preset!
+            self.duplicate_preset_names.push(preset.name);
+        } else {
+            // Add preset
+            self.total_bytes_crawled += preset.size_in_bytes;
+            self.crawled_presets.insert(preset.name.clone(), preset);
+        }
+        NextCrawlStep::Continue
+    }
+
+    /// This executes a heuristic to check whether the end of the preset list has been reached and
+    /// crawling should therefore stop.
+    ///
+    /// It looks at the preset names only. I also tried to take the chunk into account but it's not
+    /// deterministic. Getting the chunk for one preset multiple times can yield different results!
+    fn make_stop_check(&mut self, preset: &CrawledPreset) -> Option<NextCrawlStep> {
+        // If we haven't crawled anything yet, there's nothing to check.
+        let (_, last_preset) = self.crawled_presets.last()?;
+        // Check if we get multiple equally named presets in a row.
+        if preset.name == last_preset.name {
+            // Same name like last crawled preset
+            if self.same_preset_name_in_a_row_attempts <= MAX_SAME_PRESET_NAME_IN_A_ROW_ATTEMPTS {
+                // Let's tolerate that right now and still continue crawling.
+                // It's possible that the plug-in crops the preset name and therefore
+                // presets that seemingly have the same name, in fact have different ones
+                // but have the same prefix. This happened with Zebra2 VSTi, for example.
+                self.same_preset_name_in_a_row_attempts += 1;
+                // Don't add it to the list of duplicates right away because it *might* really
+                // turn out to be the end of the preset list! If it turns out it isn't, we still add
+                // it to the list of duplicates later.
+                self.same_preset_name_in_a_row = Some(preset.name.clone());
+                return Some(NextCrawlStep::Continue);
+            } else {
+                // More than max same preset names in a row! That either means the
+                // "Next preset" button doesn't work at all or we have reached the end of the
+                // preset list.
+                return Some(NextCrawlStep::Stop(
+                    PresetCrawlerStopReason::PresetNameNotChangingAnymore,
+                ));
+            }
+        }
+        // Now check if the presets that we crawl are the same ones that we crawled in the beginning.
+        if let Some((_, reference_preset)) = self
+            .crawled_presets
+            .get_index(self.same_preset_name_like_beginning_attempts as usize)
+        {
+            if preset.name == reference_preset.name {
+                // This preset has the same name as the reference preset, which is one of the
+                // presets crawled right at the beginning.
+                if self.same_preset_name_like_beginning_attempts
+                    <= MAX_SAME_PRESET_NAME_LIKE_BEGINNING_ATTEMPTS
+                {
+                    // Let's tolerate that right now and still continue crawling.
+                    // It's possible that the plug-in doesn't navigate through the preset list in
+                    // a linear way.
+                    self.same_preset_name_like_beginning_attempts += 1;
+                    // Don't add it to the list of duplicates right away because it *might* really
+                    // turn out to be the beginning of the preset list! If it turns out it isn't,
+                    // we still add it to the list of duplicates later.
+                    self.same_preset_names_like_beginning
+                        .push(preset.name.clone());
+                    return Some(NextCrawlStep::Continue);
+                } else {
+                    // More than max matches with the beginning! That either means the plug-in
+                    // navigates in a *very* non-linear fashion through the preset list or we have
+                    // reached the end of the preset list and restarted at its beginning.
+                    return Some(NextCrawlStep::Stop(
+                        PresetCrawlerStopReason::PresetNameLikeBeginning,
+                    ));
+                }
+            }
+        }
+        None
+    }
+}
+
+enum NextCrawlStep {
+    Continue,
+    Stop(PresetCrawlerStopReason),
+}
+
+#[derive(Debug)]
+pub struct CrawledPreset {
+    name: String,
+    offset: u64,
+    size_in_bytes: usize,
+    destination: Utf8PathBuf,
+}
+
+impl CrawledPreset {
+    pub fn name(&self) -> &str {
+        &self.name
+    }
+
+    pub fn destination(&self) -> &Utf8Path {
+        &self.destination
+    }
+}
+
+pub struct CrawlPresetArgs<F> {
+    pub fx: Fx,
+    pub next_preset_cursor_pos: MouseCursorPosition,
+    pub state: SharedPresetCrawlingState,
+    pub stop_if_destination_exists: bool,
+    pub never_stop_crawling: bool,
+    pub bring_focus_back_to_crawler: F,
+}
+
+pub async fn crawl_presets<F>(
+    args: CrawlPresetArgs<F>,
+) -> Result<PresetCrawlingOutcome, Box<dyn Error + Send + Sync>>
+where
+    F: Fn() + 'static,
+{
+    let reaper_resource_dir = Reaper::get().resource_path();
+    // No need to fall back to chunk-based FX info because Pot is experimental, and we can assume it's used
+    // with recent REAPER versions.
+    let fx_info = args.fx.info()?;
+    let plugin_id = get_plugin_id_from_fx_info(&fx_info);
+    let mut mouse = EnigoMouse::new();
+    let escape_catcher = EscapeCatcher::new();
+    let mut chunks_file = tempfile::tempfile()?;
+    let mut current_file_offset = 0u64;
+    loop {
+        // Check if escape has been pressed
+        if escape_catcher.escape_was_pressed() {
+            return Ok(PresetCrawlingOutcome::new(
+                chunks_file,
+                PresetCrawlerStopReason::Interrupted,
+            ));
+        }
+        // Get preset name
+        let name = args
+            .fx
+            .preset_name()
+            .ok_or("couldn't get preset name")?
+            .into_string();
+        {
+            // Query chunk and save it in temporary file
+            let fx_chunk = args.fx.chunk()?;
+            let fx_chunk_content = fx_chunk.content();
+            let fx_chunk_bytes = fx_chunk_content.as_bytes();
+            chunks_file.write_all(fx_chunk_bytes)?;
+            chunks_file.flush()?;
+            // Determine where on the disk the RfxChain file should end up
+            let destination = determine_preset_file_destination(
+                &fx_info,
+                &reaper_resource_dir,
+                &name,
+                plugin_id.as_ref(),
+            );
+            if args.stop_if_destination_exists && destination.exists() {
+                return Ok(PresetCrawlingOutcome::new(
+                    chunks_file,
+                    PresetCrawlerStopReason::DestinationFileExists,
+                ));
+            }
+            // Build crawled preset
+            let crawled_preset = CrawledPreset {
+                destination,
+                name,
+                offset: current_file_offset,
+                size_in_bytes: fx_chunk_bytes.len(),
+            };
+            current_file_offset += fx_chunk_bytes.len() as u64;
+            let next_step = blocking_lock_arc(&args.state, "crawl_presets 3")
+                .add_preset(crawled_preset, args.never_stop_crawling);
+            match next_step {
+                NextCrawlStep::Stop(reason) => {
+                    return Ok(PresetCrawlingOutcome::new(chunks_file, reason));
+                }
+                NextCrawlStep::Continue => {}
+            }
+        }
+        // Click "Next preset" button
+        args.fx.show_in_floating_window()?;
+        mouse.set_cursor_position(args.next_preset_cursor_pos)?;
+        moment().await;
+        mouse.press(MouseButton::Left)?;
+        moment().await;
+        mouse.release(MouseButton::Left)?;
+        a_bit_longer().await;
+    }
+}
+
+fn determine_preset_file_destination(
+    fx_info: &FxInfo,
+    reaper_resource_dir: &Utf8Path,
+    preset_name: &str,
+    plugin_id: Option<&PluginId>,
+) -> Utf8PathBuf {
+    if let Some(persistent_preset_id) = find_shimmable_preset(plugin_id, preset_name) {
+        // Matched with existing unsupported preset. Create RfxChain file, a so called shim file,
+        // but not in the FX chain directory because we don't want it to show up in the FX chain
+        // database. Instead, we want the original preset (probably in the Komplete database)
+        // to become loadable. There's logic in our preset loading mechanism that looks for
+        // a shim file if it realizes that the preset can't be loaded. A kind of fallback!
+        get_shim_file_path(reaper_resource_dir, &persistent_preset_id)
+    } else {
+        // No match with existing unsupported preset
+        let sanitized_effect_name = sanitize_filename::sanitize(&fx_info.effect_name);
+        let file_name = format!("{}.RfxChain", &preset_name);
+        let sanitized_file_name = sanitize_filename::sanitize(file_name);
+        reaper_resource_dir
+            .join("FXChains/Pot")
+            .join(sanitized_effect_name)
+            .join(sanitized_file_name)
+    }
+}
+
+/// Returns the file name of the original preset.
+fn find_shimmable_preset(
+    plugin_id: Option<&PluginId>,
+    preset_name: &str,
+) -> Option<PersistentPresetId> {
+    let plugin_id = plugin_id?;
+    pot_db().find_unsupported_preset_matching(plugin_id, preset_name)
+}
+
+fn get_plugin_id_from_fx_info(fx_info: &FxInfo) -> Option<PluginId> {
+    let plugin_id = match fx_info.sub_type_expression.as_str() {
+        "VST" | "VSTi" => PluginId::vst2(parse_vst2_magic_number(&fx_info.id).ok()?),
+        "VST3" | "VST3i" => PluginId::vst3(parse_vst3_uid(&fx_info.id).ok()?),
+        // Komplete doesn't support CLAP or JS anyway, so not important right now.
+        _ => return None,
+    };
+    Some(plugin_id)
+}
+
+pub async fn import_crawled_presets(
+    state: SharedPresetCrawlingState,
+    mut chunks_file: File,
+) -> Result<(), Box<dyn Error + Send + Sync>> {
+    loop {
+        let p = blocking_lock_arc(&state, "import_crawled_presets").pop_crawled_preset();
+        let Some(p) = p else {
+            break;
+        };
+        let dest_file_path = &p.destination;
+        let dest_dir_path = p.destination.parent().ok_or("destination without parent")?;
+        fs::create_dir_all(dest_dir_path)?;
+        chunks_file.seek(SeekFrom::Start(p.offset))?;
+        let mut buf = vec![0; p.size_in_bytes];
+        chunks_file.read_exact(&mut buf)?;
+        fs::write(dest_file_path, buf)?;
+    }
+    Ok(())
+}
+
+async fn a_bit_longer() {
+    millis(100).await;
+}
+
+async fn moment() {
+    millis(50).await;
+}
+
+const MAX_SAME_PRESET_NAME_IN_A_ROW_ATTEMPTS: u32 = 10;
+const MAX_SAME_PRESET_NAME_LIKE_BEGINNING_ATTEMPTS: u32 = 10;
+
+pub fn get_shim_file_path(
+    reaper_resource_dir: &Utf8Path,
+    preset_id: &PersistentPresetId,
+) -> Utf8PathBuf {
+    // We don't need to
+    let hash =
+        hash_util::calculate_persistent_non_crypto_hash_one_shot(preset_id.to_string().as_bytes());
+    let file_name = file_util::convert_hash_to_dir_structure(hash, ".RfxChain");
+    reaper_resource_dir
+        .join("Helgoboss/Pot/shims")
+        .join(file_name)
+}
+
+#[derive(Copy, Clone, Eq, PartialEq, Debug)]
+pub enum PresetCrawlerStopReason {
+    Interrupted,
+    DestinationFileExists,
+    PresetNameNotChangingAnymore,
+    PresetNameLikeBeginning,
+}

plugin-reaper-relearn/pot/src/preview_recorder.rs

@@ -0,0 +1,254 @@
+use crate::provider_database::{
+    FIL_IS_AVAILABLE_TRUE, FIL_IS_SUPPORTED_TRUE, FIL_PRODUCT_KIND_INSTRUMENT,
+};
+use crate::{
+    pot_db, preview_exists, BuildInput, Destination, EscapeCatcher, FilterItemId,
+    LoadPresetOptions, LoadPresetWindowBehavior, PluginId, PotPreset, PotPresetKind, PresetWithId,
+    ProductId, SharedRuntimePotUnit,
+};
+use base::future_util::millis;
+use base::hash_util::PersistentHash;
+use base::{blocking_lock_arc, blocking_write_lock, file_util};
+use camino::{Utf8Path, Utf8PathBuf};
+use helgobox_api::persistence::PotFilterKind;
+use reaper_high::{Project, Reaper};
+use reaper_medium::{CommandId, OpenProjectBehavior, ProjectContext, ProjectInfoAttributeKey};
+use std::error::Error;
+use std::sync::{Arc, RwLock};
+
+pub type SharedPreviewRecorderState = Arc<RwLock<PreviewRecorderState>>;
+
+#[derive(Debug)]
+pub struct PreviewRecorderState {
+    pub todos: Vec<PresetWithId>,
+    pub failures: Vec<PreviewRecorderFailure>,
+}
+
+impl PreviewRecorderState {
+    pub fn new(todos: Vec<PresetWithId>) -> Self {
+        Self {
+            todos,
+            failures: vec![],
+        }
+    }
+}
+
+#[derive(Debug)]
+pub struct PreviewRecorderFailure {
+    pub preset: PresetWithId,
+    pub reason: String,
+}
+
+impl AsRef<PotPreset> for PreviewRecorderFailure {
+    fn as_ref(&self) -> &PotPreset {
+        &self.preset.preset
+    }
+}
+
+pub struct RecordPreviewsArgs<'a> {
+    pub shared_pot_unit: SharedRuntimePotUnit,
+    pub state: SharedPreviewRecorderState,
+    /// RPP file that is used to render the previews
+    pub preview_rpp: &'a Utf8Path,
+    pub config: PreviewOutputConfig,
+}
+
+#[derive(Clone, Debug)]
+pub enum PreviewOutputConfig {
+    /// For playback within Pot Browser.
+    ForPotBrowserPlayback,
+    /// For export to custom location.
+    Export(ExportPreviewOutputConfig),
+}
+
+#[derive(Clone, Debug)]
+pub struct ExportPreviewOutputConfig {
+    /// Where to put the preview files.
+    pub base_dir: Utf8PathBuf,
+}
+
+pub async fn record_previews(args: RecordPreviewsArgs<'_>) -> Result<(), Box<dyn Error>> {
+    let reaper = Reaper::get();
+    let reaper_resource_dir = reaper.resource_path();
+    // Open preview project template in new tab
+    let project = open_preview_project_in_new_tab(args.preview_rpp);
+    moment().await;
+    // Prepare destination (first track, first FX)
+    let first_track = project
+        .first_track()
+        .ok_or("preview must have at least one track")?;
+    let destination = Destination {
+        chain: first_track.normal_fx_chain(),
+        fx_index: 0,
+    };
+    let cloned_state = args.state.clone();
+    let report_failure = move |preset: PresetWithId, reason: String| {
+        let mut state = blocking_write_lock(&cloned_state, "record_previews state 2");
+        let failure = PreviewRecorderFailure { preset, reason };
+        state.failures.push(failure);
+    };
+    let escape_catcher = EscapeCatcher::new();
+    // Loop over the preset list
+    loop {
+        // Check if escape has been pressed
+        if escape_catcher.escape_was_pressed() {
+            break;
+        }
+        // Take new preset to be recorded
+        moment().await;
+        let Some(preset_with_id) = blocking_write_lock(&args.state, "record_previews state")
+            .todos
+            .pop()
+        else {
+            // Done!
+            break;
+        };
+        // Determine destination file
+        let preset = &preset_with_id.preset;
+        let preview_file_path = match &args.config {
+            PreviewOutputConfig::ForPotBrowserPlayback => {
+                // Prefer creating preview file name based on preset content. That means whenever the
+                // content changes, we get a different preview file name. That is cool.
+                let hash = preset.common.content_or_id_hash();
+                get_preview_file_path_from_hash(&reaper_resource_dir, hash)
+            }
+            PreviewOutputConfig::Export(c) => {
+                let product_dir_name = preset
+                    .common
+                    .product_name
+                    .as_deref()
+                    .unwrap_or("Unknown product");
+                c.base_dir.join(product_dir_name).join(&preset.common.name)
+            }
+        };
+        // Load preset
+        let options = LoadPresetOptions {
+            window_behavior_override: Some(LoadPresetWindowBehavior::AlwaysShow),
+            audio_sample_behavior: Default::default(),
+        };
+        {
+            let load_result = blocking_lock_arc(&args.shared_pot_unit, "record_previews pot unit")
+                .load_preset_at(preset, options, &|_| Ok(destination.clone()));
+            if let Err(e) = load_result {
+                report_failure(preset_with_id, e.to_string());
+                continue;
+            }
+        }
+        moment().await;
+        // Record preview
+        if let Err(e) = render_to_file(project, &preview_file_path) {
+            report_failure(preset_with_id, e.to_string());
+        }
+    }
+    Ok(())
+}
+
+fn render_to_file(project: Project, full_path: &Utf8Path) -> Result<(), Box<dyn Error>> {
+    let reaper = Reaper::get();
+    let medium_reaper = reaper.medium_reaper();
+    let dir = full_path.parent().ok_or("render path has not parent")?;
+    let file_name = full_path
+        .file_name()
+        .ok_or("render path has no file name")?;
+    medium_reaper.get_set_project_info_string_set(
+        ProjectContext::Proj(project.raw()),
+        ProjectInfoAttributeKey::RenderFile,
+        dir.as_str(),
+    )?;
+    medium_reaper.get_set_project_info_string_set(
+        ProjectContext::Proj(project.raw()),
+        ProjectInfoAttributeKey::RenderPattern,
+        file_name,
+    )?;
+    // "File: Render project, using the most recent render settings, auto-close render dialog"
+    reaper
+        .main_section()
+        .action_by_command_id(CommandId::new(42230))
+        .invoke_as_trigger(Some(project), None)?;
+    Ok(())
+}
+
+fn open_preview_project_in_new_tab(preview_rpp: &Utf8Path) -> Project {
+    let reaper = Reaper::get();
+    let project = reaper.create_empty_project_in_new_tab();
+    let mut behavior = OpenProjectBehavior::default();
+    behavior.prompt = false;
+    behavior.open_as_template = true;
+    reaper
+        .medium_reaper()
+        .main_open_project(preview_rpp, behavior);
+    project
+}
+
+async fn moment() {
+    millis(200).await;
+}
+
+pub fn get_preview_file_path_from_hash(
+    reaper_resource_dir: &Utf8Path,
+    hash: PersistentHash,
+) -> Utf8PathBuf {
+    let file_name = file_util::convert_hash_to_dir_structure(hash, ".ogg");
+    reaper_resource_dir
+        .join("Helgoboss/Pot/previews")
+        .join(file_name)
+}
+
+/// Can take long.
+pub fn prepare_preview_recording(
+    mut build_input: BuildInput,
+    output_config: &PreviewOutputConfig,
+) -> Vec<PresetWithId> {
+    // We want only available and supported instruments
+    build_input.filters.set(
+        PotFilterKind::ProductKind,
+        Some(FilterItemId(Some(FIL_PRODUCT_KIND_INSTRUMENT))),
+    );
+    build_input.filters.set(
+        PotFilterKind::IsAvailable,
+        Some(FilterItemId(Some(FIL_IS_AVAILABLE_TRUE))),
+    );
+    build_input.filters.set(
+        PotFilterKind::IsSupported,
+        Some(FilterItemId(Some(FIL_IS_SUPPORTED_TRUE))),
+    );
+    // Gather
+    let mut presets = pot_db().gather_presets(build_input);
+    if matches!(output_config, PreviewOutputConfig::ForPotBrowserPlayback) {
+        // Take only those that don't have a preview within Pot Browser yet
+        let reaper_resource_dir = Reaper::get().resource_path();
+        presets.retain(|p| !preview_exists(&p.preset, &reaper_resource_dir));
+    }
+    // Reverse, so we can efficiently pop from the front later on
+    presets.reverse();
+    // Sort by plug-in
+    presets.sort_by(|left, right| bucket(left).cmp(&bucket(right)));
+    presets
+}
+
+fn bucket(preset_with_id: &PresetWithId) -> BucketId {
+    let preset = &preset_with_id.preset;
+    if !preset.common.plugin_ids.is_empty() {
+        return BucketId::Plugin(&preset.common.plugin_ids);
+    }
+    if !preset.common.product_ids.is_empty() {
+        return BucketId::ProductId(&preset.common.product_ids);
+    }
+    if let PotPresetKind::FileBased(kind) = &preset.kind {
+        return BucketId::FileExtension(&kind.file_ext);
+    }
+    BucketId::Remaining
+}
+
+#[derive(Eq, PartialEq, Ord, PartialOrd)]
+enum BucketId<'a> {
+    /// The plug-in ID is certainly the best criteria here! We have that for all databases except
+    /// Komplete. For FX chains and track templates, we might have multiple plug-ins. The order of
+    /// these plug-ins is important because different orders will reload the plug-ins.
+    Plugin(&'a [PluginId]),
+    /// The next best bet is
+    ProductId(&'a [ProductId]),
+    /// And finally: File extension.
+    FileExtension(&'a str),
+    Remaining,
+}

plugin-reaper-relearn/pot/src/provider_database.rs

@@ -0,0 +1,132 @@
+use crate::plugins::{PluginDatabase, ProductKind};
+use crate::{
+    Fil, FilterItem, FilterItemId, GenericFilterItemCollections, HasFilterItemId, InnerBuildInput,
+    InnerPresetId, PersistentDatabaseId, PotPreset, ProductId,
+};
+use enumset::{enum_set, EnumSet};
+use helgobox_api::persistence::PotFilterKind;
+use std::borrow::Cow;
+use std::error::Error;
+
+/// A database ID that's only stable during the runtime of ReaLearn.
+#[derive(Copy, Clone, Eq, PartialEq, Ord, PartialOrd, Hash, Debug)]
+pub struct DatabaseId(pub u32);
+
+pub trait Database {
+    fn persistent_id(&self) -> &PersistentDatabaseId;
+
+    // TODO-medium-performace Maybe we should require this to be a reference.
+    fn name(&self) -> Cow<str>;
+
+    // TODO-medium-performace Maybe we should require this to be a reference.
+    fn description(&self) -> Cow<str>;
+
+    fn supported_advanced_filter_kinds(&self) -> EnumSet<PotFilterKind> {
+        enum_set!()
+    }
+
+    fn refresh(&mut self, context: &ProviderContext) -> Result<(), Box<dyn Error>>;
+
+    fn query_filter_collections(
+        &self,
+        context: &ProviderContext,
+        input: InnerBuildInput,
+        affected_kinds: EnumSet<PotFilterKind>,
+    ) -> Result<InnerFilterItemCollections, Box<dyn Error>>;
+
+    fn query_presets(
+        &self,
+        context: &ProviderContext,
+        input: InnerBuildInput,
+    ) -> Result<Vec<SortablePresetId>, Box<dyn Error>>;
+
+    fn find_preset_by_id(
+        &self,
+        context: &ProviderContext,
+        preset_id: InnerPresetId,
+    ) -> Option<PotPreset>;
+
+    /// Tries to find a preset that belongs to the given product and has the given name *and*
+    /// most importantly a preset file format that can't be loaded by Pot Browser.
+    ///
+    /// This is used by the preset crawler to identify whether a crawled preset can be used to
+    /// make a preset with an unsupported format actually loadable. Only makes sense for Komplete
+    /// at the moment because this is the only database which exposes unsupported presets.
+    fn find_unsupported_preset_matching(
+        &self,
+        product_id: ProductId,
+        preset_name: &str,
+    ) -> Option<PotPreset> {
+        let _ = (product_id, preset_name);
+        None
+    }
+}
+
+pub type InnerFilterItemCollections = GenericFilterItemCollections<InnerFilterItem>;
+
+pub enum InnerFilterItem {
+    /// A unique final filter item. Only makes sense within a specific database and within the
+    /// context of a specific pot filter item kind. Not deduplicated.
+    Unique(FilterItem),
+    /// A filter item representing a particular product (product for which the preset is made).
+    ///
+    /// Will be deduplicated by the pot database!
+    Product(ProductId),
+}
+
+impl HasFilterItemId for InnerFilterItem {
+    fn id(&self) -> FilterItemId {
+        match self {
+            InnerFilterItem::Unique(i) => i.id,
+            InnerFilterItem::Product(i) => FilterItemId(Some(Fil::Product(*i))),
+        }
+    }
+}
+
+pub struct SortablePresetId {
+    pub inner_preset_id: InnerPresetId,
+    pub preset_name: String,
+}
+
+impl SortablePresetId {
+    pub fn new(i: u32, preset_name: String) -> Self {
+        Self {
+            inner_preset_id: InnerPresetId(i),
+            preset_name,
+        }
+    }
+}
+
+#[derive(Copy, Clone)]
+pub struct ProviderContext<'a> {
+    pub plugin_db: &'a PluginDatabase,
+}
+
+impl<'a> ProviderContext<'a> {
+    pub fn new(plugin_db: &'a PluginDatabase) -> Self {
+        Self { plugin_db }
+    }
+}
+
+/// Komplete content path state ID = 1
+pub const FIL_IS_AVAILABLE_TRUE: Fil = Fil::Boolean(true);
+/// Komplete content path state ID = 4
+pub const FIL_IS_AVAILABLE_FALSE: Fil = Fil::Boolean(false);
+pub const FIL_IS_SUPPORTED_TRUE: Fil = Fil::Boolean(true);
+pub const FIL_IS_SUPPORTED_FALSE: Fil = Fil::Boolean(false);
+pub const FIL_IS_FAVORITE_TRUE: Fil = Fil::Boolean(true);
+pub const FIL_IS_FAVORITE_FALSE: Fil = Fil::Boolean(false);
+/// Komplete content type ID = 1
+pub const FIL_IS_USER_PRESET_TRUE: Fil = Fil::Boolean(true);
+/// Komplete content type ID = 2
+pub const FIL_IS_USER_PRESET_FALSE: Fil = Fil::Boolean(false);
+/// Komplete product type ID = 1
+pub const FIL_PRODUCT_KIND_INSTRUMENT: Fil = Fil::ProductKind(ProductKind::Instrument);
+/// Komplete product type ID = 2
+pub const FIL_PRODUCT_KIND_EFFECT: Fil = Fil::ProductKind(ProductKind::Effect);
+/// Komplete product type ID = 4
+pub const FIL_PRODUCT_KIND_LOOP: Fil = Fil::ProductKind(ProductKind::Loop);
+/// Komplete product type ID = 8
+pub const FIL_PRODUCT_KIND_ONE_SHOT: Fil = Fil::ProductKind(ProductKind::OneShot);
+pub const FIL_HAS_PREVIEW_TRUE: Fil = Fil::Boolean(true);
+pub const FIL_HAS_PREVIEW_FALSE: Fil = Fil::Boolean(false);

plugin-reaper-relearn/pot/src/providers/defaults.rs

@@ -0,0 +1,151 @@
+use crate::provider_database::{
+    Database, InnerFilterItem, InnerFilterItemCollections, ProviderContext, SortablePresetId,
+};
+use crate::{
+    create_plugin_factory_preset, FilterInput, InnerBuildInput, InnerPresetId,
+    PersistentDatabaseId, PersistentInnerPresetId, PersistentPresetId, PluginId,
+    PluginIdInPipeFormat, PotPreset, SearchInput,
+};
+use std::borrow::Cow;
+
+use crate::plugins::PluginCommon;
+use either::Either;
+use enumset::{enum_set, EnumSet};
+use helgobox_api::persistence::PotFilterKind;
+use itertools::Itertools;
+use std::error::Error;
+use std::iter;
+
+pub struct DefaultsDatabase {
+    persistent_id: PersistentDatabaseId,
+    plugins: Vec<PluginCommon>,
+}
+
+impl Default for DefaultsDatabase {
+    fn default() -> Self {
+        Self {
+            persistent_id: PersistentDatabaseId::new("fx-defaults".to_string()),
+            plugins: vec![],
+        }
+    }
+}
+
+impl DefaultsDatabase {
+    pub fn open() -> Self {
+        Default::default()
+    }
+
+    fn query_presets_internal<'a>(
+        &'a self,
+        filter_input: &'a FilterInput,
+    ) -> impl Iterator<Item = (usize, &'a PluginCommon)> + 'a {
+        let matches = !filter_input.filters.wants_user_presets_only();
+        if !matches {
+            return Either::Left(iter::empty());
+        }
+        let iter = self.plugins.iter().enumerate().filter(|(i, p)| {
+            let id = InnerPresetId(*i as _);
+            filter_input.everything_matches(Some(&p.core), id)
+        });
+        Either::Right(iter)
+    }
+}
+
+impl Database for DefaultsDatabase {
+    fn persistent_id(&self) -> &PersistentDatabaseId {
+        &self.persistent_id
+    }
+
+    fn name(&self) -> Cow<str> {
+        "FX defaults".into()
+    }
+
+    fn description(&self) -> Cow<str> {
+        "Default factory presets for all of your plug-ins".into()
+    }
+
+    fn supported_advanced_filter_kinds(&self) -> EnumSet<PotFilterKind> {
+        enum_set!(PotFilterKind::Bank)
+    }
+
+    fn refresh(&mut self, ctx: &ProviderContext) -> Result<(), Box<dyn Error>> {
+        // We clone the plug-in list so we can create own own order and maintain stable IDs.
+        self.plugins = ctx.plugin_db.plugins().map(|p| p.common.clone()).collect();
+        Ok(())
+    }
+
+    fn query_filter_collections(
+        &self,
+        _: &ProviderContext,
+        input: InnerBuildInput,
+        _: EnumSet<PotFilterKind>,
+    ) -> Result<InnerFilterItemCollections, Box<dyn Error>> {
+        let mut new_filters = *input.filter_input.filters;
+        new_filters.clear_this_and_dependent_filters(PotFilterKind::Bank);
+        let product_items = self
+            .query_presets_internal(&input.filter_input.with_filters(&new_filters))
+            .map(|(_, plugin)| plugin.core.product_id)
+            .unique()
+            .map(InnerFilterItem::Product)
+            .collect();
+        let mut collections = InnerFilterItemCollections::empty();
+        collections.set(PotFilterKind::Bank, product_items);
+        Ok(collections)
+    }
+
+    fn query_presets(
+        &self,
+        _: &ProviderContext,
+        input: InnerBuildInput,
+    ) -> Result<Vec<SortablePresetId>, Box<dyn Error>> {
+        let preset_ids = self
+            .query_presets_internal(&input.filter_input)
+            .filter(|(_, entry)| {
+                let search_input = DefaultSearchInput { entry };
+                input.search_evaluator.matches(search_input)
+            })
+            .map(|(i, _)| SortablePresetId::new(i as _, PRESET_NAME.to_string()))
+            .collect();
+        Ok(preset_ids)
+    }
+
+    fn find_preset_by_id(
+        &self,
+        _: &ProviderContext,
+        preset_id: InnerPresetId,
+    ) -> Option<PotPreset> {
+        let plugin = self.plugins.get(preset_id.0 as usize)?;
+        let persistent_id = PersistentPresetId::new(
+            self.persistent_id.clone(),
+            create_persistent_inner_id(&plugin.core.id),
+        );
+        let preset = create_plugin_factory_preset(plugin, persistent_id, PRESET_NAME.to_string());
+        Some(preset)
+    }
+}
+
+const PRESET_NAME: &str = "<Default>";
+
+/// Example: `vst2|1967946098`
+fn create_persistent_inner_id(plugin_id: &PluginId) -> PersistentInnerPresetId {
+    let id = PluginIdInPipeFormat(plugin_id).to_string();
+    PersistentInnerPresetId::new(id)
+}
+
+struct DefaultSearchInput<'a> {
+    entry: &'a PluginCommon,
+}
+
+impl SearchInput for DefaultSearchInput<'_> {
+    fn preset_name(&self) -> &str {
+        PRESET_NAME
+    }
+
+    fn product_name(&self) -> Option<Cow<str>> {
+        Some(self.entry.to_string().into())
+    }
+
+    fn file_extension(&self) -> Option<&str> {
+        None
+    }
+}

plugin-reaper-relearn/pot/src/providers/directory.rs

@@ -0,0 +1,293 @@
+use crate::provider_database::{
+    Database, InnerFilterItem, InnerFilterItemCollections, ProviderContext, SortablePresetId,
+};
+use crate::{
+    FiledBasedPotPresetKind, FilterInput, InnerBuildInput, InnerPresetId, PersistentDatabaseId,
+    PersistentInnerPresetId, PersistentPresetId, PipeEscaped, PluginId, PotPreset, PotPresetCommon,
+    PotPresetKind, SearchInput,
+};
+use std::borrow::Cow;
+
+use crate::plugins::{PluginCore, PluginDatabase};
+use base::hash_util::{NonCryptoHashSet, NonCryptoIndexMap, PersistentHash, PersistentHasher};
+use camino::Utf8PathBuf;
+use either::Either;
+use enumset::{enum_set, EnumSet};
+use helgobox_api::persistence::PotFilterKind;
+use itertools::Itertools;
+use std::error::Error;
+use std::ffi::OsStr;
+use std::fs::File;
+use std::hash::Hasher;
+use std::io::{BufRead, BufReader};
+use std::iter;
+use std::path::Path;
+use walkdir::WalkDir;
+
+pub struct DirectoryDatabase {
+    persistent_id: PersistentDatabaseId,
+    root_dir: Utf8PathBuf,
+    valid_extensions: NonCryptoHashSet<&'static OsStr>,
+    name: &'static str,
+    description: &'static str,
+    entries: Vec<PresetEntry>,
+}
+
+pub struct DirectoryDbConfig {
+    pub persistent_id: PersistentDatabaseId,
+    pub root_dir: Utf8PathBuf,
+    pub valid_extensions: &'static [&'static str],
+    pub name: &'static str,
+    pub description: &'static str,
+}
+
+impl DirectoryDatabase {
+    pub fn open(config: DirectoryDbConfig) -> Result<Self, Box<dyn Error>> {
+        if !config.root_dir.try_exists()? {
+            return Err("path to root directory doesn't exist".into());
+        }
+        let db = Self {
+            persistent_id: config.persistent_id,
+            name: config.name,
+            entries: Default::default(),
+            root_dir: config.root_dir,
+            valid_extensions: config.valid_extensions.iter().map(OsStr::new).collect(),
+            description: config.description,
+        };
+        Ok(db)
+    }
+
+    fn query_presets_internal<'a>(
+        &'a self,
+        filter_input: &'a FilterInput,
+    ) -> impl Iterator<Item = (usize, &'a PresetEntry)> + 'a {
+        let matches = !filter_input.filters.wants_factory_presets_only();
+        if !matches {
+            return Either::Left(iter::empty());
+        }
+        let iter = self.entries.iter().enumerate().filter(|(id, e)| {
+            let id = InnerPresetId(*id as _);
+            e.plugin_cores
+                .values()
+                .any(|core| filter_input.everything_matches(Some(core), id))
+        });
+        Either::Right(iter)
+    }
+}
+
+struct PresetEntry {
+    preset_name: String,
+    relative_path: String,
+    plugin_cores: NonCryptoIndexMap<PluginId, PluginCore>,
+    content_hash: PersistentHash,
+}
+
+impl Database for DirectoryDatabase {
+    fn persistent_id(&self) -> &PersistentDatabaseId {
+        &self.persistent_id
+    }
+
+    fn name(&self) -> Cow<str> {
+        self.name.into()
+    }
+
+    fn description(&self) -> Cow<str> {
+        self.description.into()
+    }
+
+    fn supported_advanced_filter_kinds(&self) -> EnumSet<PotFilterKind> {
+        enum_set!(PotFilterKind::Bank)
+    }
+
+    fn refresh(&mut self, ctx: &ProviderContext) -> Result<(), Box<dyn Error>> {
+        self.entries = WalkDir::new(&self.root_dir)
+            .follow_links(true)
+            .into_iter()
+            .filter_map(|entry| {
+                let entry = entry.ok()?;
+                if !entry.file_type().is_file() {
+                    return None;
+                }
+                let extension = entry.path().extension()?;
+                if !self.valid_extensions.contains(extension) {
+                    return None;
+                }
+                let relative_path = entry.path().strip_prefix(&self.root_dir).ok()?;
+                // Immediately exclude relative paths that can't be represented as valid UTF-8.
+                // Otherwise we will potentially open a can of worms (regarding persistence etc.).
+                let processing_output = process_file(entry.path(), ctx.plugin_db).ok()?;
+                let preset_entry = PresetEntry {
+                    preset_name: entry.path().file_stem()?.to_str()?.to_string(),
+                    relative_path: relative_path.to_str()?.to_string(),
+                    plugin_cores: processing_output.used_plugins,
+                    content_hash: processing_output.content_hash,
+                };
+                Some(preset_entry)
+            })
+            .collect();
+        Ok(())
+    }
+
+    fn query_filter_collections(
+        &self,
+        _: &ProviderContext,
+        input: InnerBuildInput,
+        _: EnumSet<PotFilterKind>,
+    ) -> Result<InnerFilterItemCollections, Box<dyn Error>> {
+        let mut new_filters = *input.filter_input.filters;
+        new_filters.clear_this_and_dependent_filters(PotFilterKind::Bank);
+        let product_items = self
+            .query_presets_internal(&input.filter_input.with_filters(&new_filters))
+            .flat_map(|(_, entry)| entry.plugin_cores.values().map(|core| core.product_id))
+            .unique()
+            .map(InnerFilterItem::Product)
+            .collect();
+        let mut collections = InnerFilterItemCollections::empty();
+        collections.set(PotFilterKind::Bank, product_items);
+        Ok(collections)
+    }
+
+    fn query_presets(
+        &self,
+        ctx: &ProviderContext,
+        input: InnerBuildInput,
+    ) -> Result<Vec<SortablePresetId>, Box<dyn Error>> {
+        let preset_ids = self
+            .query_presets_internal(&input.filter_input)
+            .filter(|(_, entry)| {
+                let search_input = DirectorySearchInput {
+                    ctx,
+                    preset_entry: entry,
+                };
+                input.search_evaluator.matches(search_input)
+            })
+            .map(|(i, entry)| SortablePresetId::new(i as _, entry.preset_name.clone()))
+            .collect();
+        Ok(preset_ids)
+    }
+
+    fn find_preset_by_id(
+        &self,
+        ctx: &ProviderContext,
+        preset_id: InnerPresetId,
+    ) -> Option<PotPreset> {
+        let preset_entry = self.entries.get(preset_id.0 as usize)?;
+        let preset = PotPreset {
+            common: PotPresetCommon {
+                persistent_id: PersistentPresetId::new(
+                    self.persistent_id().clone(),
+                    create_persistent_inner_id(preset_entry),
+                ),
+                name: preset_entry.preset_name.clone(),
+                context_name: Path::new(&preset_entry.relative_path)
+                    .parent()
+                    .and_then(|p| Some(p.to_str()?.to_string())),
+                plugin_ids: preset_entry.plugin_cores.values().map(|c| c.id).collect(),
+                product_ids: preset_entry
+                    .plugin_cores
+                    .values()
+                    .map(|c| c.product_id)
+                    .collect(),
+                product_name: build_product_name(ctx, preset_entry),
+                content_hash: Some(preset_entry.content_hash),
+                db_specific_preview_file: None,
+                is_supported: true,
+                is_available: !preset_entry.plugin_cores.is_empty(),
+                metadata: Default::default(),
+            },
+            kind: PotPresetKind::FileBased(FiledBasedPotPresetKind {
+                file_ext: get_file_extension(&preset_entry.relative_path).to_string(),
+                path: self.root_dir.join(&preset_entry.relative_path),
+            }),
+        };
+        Some(preset)
+    }
+}
+
+struct FileProcessingOutput {
+    content_hash: PersistentHash,
+    used_plugins: NonCryptoIndexMap<PluginId, PluginCore>,
+}
+
+/// Finds used plug-ins in a REAPER-XML-like text file (e.g. RPP, RfxChain, RTrackTemplate).
+///
+/// Examples entries:
+///
+/// ```text
+///     <VST "VSTi: Zebra2 (u-he)" Zebra2.vst 0 Schmackes 1397572658<565354534D44327A6562726132000000> ""
+///     <VST "VSTi: ReaSamplOmatic5000 (Cockos)"
+///     <CLAP "CLAPi: Surge XT (Surge Synth Team)"
+/// ```
+fn process_file(
+    path: &Path,
+    plugin_db: &PluginDatabase,
+) -> Result<FileProcessingOutput, Box<dyn Error>> {
+    let file = File::open(path)?;
+    let mut used_plugins = NonCryptoIndexMap::default();
+    let mut buffer = String::new();
+    let mut reader = BufReader::new(&file);
+    let mut hasher = PersistentHasher::new();
+    while let Ok(count) = reader.read_line(&mut buffer) {
+        if count == 0 {
+            // EOF
+            break;
+        }
+        hasher.write(buffer.as_bytes());
+        let line = buffer.trim();
+        if let Some(plugin) = plugin_db.detect_plugin_from_rxml_line(line) {
+            used_plugins.insert(plugin.common.core.id, plugin.common.core);
+        }
+        buffer.clear();
+    }
+    let output = FileProcessingOutput {
+        content_hash: hasher.digest_128(),
+        used_plugins,
+    };
+    Ok(output)
+}
+
+/// Example: `Synths/Lead.RTrackTemplate`
+fn create_persistent_inner_id(preset_entry: &PresetEntry) -> PersistentInnerPresetId {
+    let escaped_path = PipeEscaped(preset_entry.relative_path.as_str());
+    PersistentInnerPresetId::new(escaped_path.to_string())
+}
+
+struct DirectorySearchInput<'a> {
+    ctx: &'a ProviderContext<'a>,
+    preset_entry: &'a PresetEntry,
+}
+
+impl SearchInput for DirectorySearchInput<'_> {
+    fn preset_name(&self) -> &str {
+        &self.preset_entry.preset_name
+    }
+
+    fn product_name(&self) -> Option<Cow<str>> {
+        let product_name = build_product_name(self.ctx, self.preset_entry)?;
+        Some(product_name.into())
+    }
+
+    fn file_extension(&self) -> Option<&str> {
+        Some(get_file_extension(&self.preset_entry.relative_path))
+    }
+}
+
+fn build_product_name(ctx: &ProviderContext, preset_entry: &PresetEntry) -> Option<String> {
+    if preset_entry.plugin_cores.len() > 1 {
+        Some("<Multiple>".to_string())
+    } else if let Some(first) = preset_entry.plugin_cores.values().next() {
+        ctx.plugin_db
+            .find_plugin_by_id(&first.id)
+            .map(|p| p.common.to_string())
+    } else {
+        None
+    }
+}
+
+fn get_file_extension(relative_path: &str) -> &str {
+    Path::new(relative_path)
+        .extension()
+        .unwrap()
+        .to_str()
+        .unwrap()
+}

plugin-reaper-relearn/pot/src/providers/ini.rs

@@ -0,0 +1,331 @@
+use crate::provider_database::{
+    Database, InnerFilterItem, InnerFilterItemCollections, ProviderContext, SortablePresetId,
+};
+use crate::{
+    FilterInput, InnerBuildInput, InnerPresetId, InternalPotPresetKind, PersistentDatabaseId,
+    PersistentInnerPresetId, PersistentPresetId, PipeEscaped, PluginKind, PotPreset,
+    PotPresetCommon, PotPresetKind, SearchInput,
+};
+use std::borrow::Cow;
+
+use crate::plugins::{Plugin, PluginCore, SuperPluginKind};
+use base::hash_util::{PersistentHash, PersistentHasher};
+use camino::Utf8PathBuf;
+use either::Either;
+use enumset::{enum_set, EnumSet};
+use helgobox_api::persistence::PotFilterKind;
+use ini::Ini;
+use itertools::Itertools;
+use std::error::Error;
+use std::hash::Hasher;
+use std::iter;
+use std::str::FromStr;
+use walkdir::WalkDir;
+
+pub struct IniDatabase {
+    persistent_id: PersistentDatabaseId,
+    root_dir: Utf8PathBuf,
+    entries: Vec<PresetEntry>,
+}
+
+impl IniDatabase {
+    pub fn open(
+        persistent_id: PersistentDatabaseId,
+        root_dir: Utf8PathBuf,
+    ) -> Result<Self, Box<dyn Error>> {
+        if !root_dir.try_exists()? {
+            return Err("path to presets root directory doesn't exist".into());
+        }
+        let db = Self {
+            persistent_id,
+            entries: Default::default(),
+            root_dir,
+        };
+        Ok(db)
+    }
+
+    fn query_presets_internal<'a>(
+        &'a self,
+        filter_input: &'a FilterInput,
+    ) -> impl Iterator<Item = (usize, &'a PresetEntry)> + 'a {
+        let matches = !filter_input.filters.wants_factory_presets_only();
+        if !matches {
+            return Either::Left(iter::empty());
+        }
+        let iter = self.entries.iter().enumerate().filter(|(i, e)| {
+            let id = InnerPresetId(*i as _);
+            filter_input.everything_matches(e.plugin.as_ref(), id)
+        });
+        Either::Right(iter)
+    }
+}
+
+struct PresetEntry {
+    preset_name: String,
+    plugin_kind: PluginKind,
+    /// Example: "Massive"
+    plugin_identifier: String,
+    /// If `None`, it means the corresponding plug-in is not installed/scanned.
+    plugin: Option<PluginCore>,
+    content_hash: Option<PersistentHash>,
+}
+
+impl Database for IniDatabase {
+    fn persistent_id(&self) -> &PersistentDatabaseId {
+        &self.persistent_id
+    }
+
+    fn name(&self) -> Cow<str> {
+        "FX presets".into()
+    }
+
+    fn description(&self) -> Cow<str> {
+        "All FX presets that you saved via \"Save preset...\" in REAPER's FX window.\n\".vstpreset\"-style presets are not yet supported!"
+            .into()
+    }
+
+    fn supported_advanced_filter_kinds(&self) -> EnumSet<PotFilterKind> {
+        enum_set!(PotFilterKind::Bank)
+    }
+
+    fn refresh(&mut self, ctx: &ProviderContext) -> Result<(), Box<dyn Error>> {
+        let file_name_regex = base::regex!(r#"(?i)(.*?)-(.*).ini"#);
+        self.entries = WalkDir::new(&self.root_dir)
+            .max_depth(1)
+            .follow_links(true)
+            .into_iter()
+            .filter_map(|entry| {
+                let entry = entry.ok()?;
+                if !entry.file_type().is_file() {
+                    return None;
+                }
+                let file_name = entry.file_name().to_str()?;
+                // Example file names:
+                // - vst-Zebra2.ini
+                // - vst3-FM8-1168312232-builtin.ini
+                // - vst-TDR Nova-builtin.ini
+                // - vst-reacomp.ini
+                // - vst3-Massive.ini
+                // - clap-org_surge-synth-team_surge-xt.ini
+                // - js-analysis_hund.ini
+                let captures = file_name_regex.captures(file_name)?;
+                let plugin_kind_str = captures.get(1)?.as_str();
+                let plugin_kind = PluginKind::from_str(plugin_kind_str).ok()?;
+                let plugin_identifier = captures.get(2)?.as_str();
+                if plugin_identifier.ends_with("-builtin") {
+                    return None;
+                }
+                let (main_plugin_identifier, shell_qualifier) =
+                    match plugin_identifier.rsplit_once('-') {
+                        // Example: vst3-Zebra2-959560201.ini
+                        // (interpret the number behind the dash as shell qualifier)
+                        Some((left, right))
+                            if right.len() >= 5 && right.chars().all(|ch| ch.is_ascii_digit()) =>
+                        {
+                            (left, Some(right))
+                        }
+                        // Examples: "vst-Tritik-Irid.ini", "vst-Zebra2.ini"
+                        _ => (plugin_identifier, None),
+                    };
+                let plugin = ctx.plugin_db.plugins().find(|p| {
+                    if p.common.core.id.kind() != plugin_kind {
+                        return false;
+                    }
+                    match &p.kind {
+                        SuperPluginKind::Vst(k) => {
+                            let unsafe_char_regex = base::regex!(r#"[^a-zA-Z0-9_]"#);
+                            let safe_main_plugin_identifier =
+                                unsafe_char_regex.replace_all(main_plugin_identifier, "_");
+                            let file_name_prefix = format!("{safe_main_plugin_identifier}.");
+                            tracing::trace!(
+                                "Test VST '{}' should start with INI plug-in file name prefix '{file_name_prefix}'",
+                                k.safe_file_name
+                            );
+                            if !k.safe_file_name.starts_with(&file_name_prefix) {
+                                return false;
+                            }
+                            let plugin_shell_qualifier = k.shell_qualifier.as_deref();
+                            if shell_qualifier != plugin_shell_qualifier {
+                                return false;
+                            }
+                            true
+                        }
+                        SuperPluginKind::Clap(k) => {
+                            let safe_plugin_id = k.id.replace('.', "_");
+                            if plugin_identifier != safe_plugin_id {
+                                return false;
+                            }
+                            true
+                        }
+                        SuperPluginKind::Js(k) => {
+                            let lowercase_safe_path = k.path.replace(['/', '\\', '.'], "_").to_lowercase();
+                            let lowercase_plugin_identifier = plugin_identifier.to_lowercase();
+                            tracing::trace!(
+                                "Test JS '{lowercase_safe_path}' vs. INI plug-in identifier '{lowercase_plugin_identifier}'"
+                            );
+                            if lowercase_plugin_identifier != lowercase_safe_path {
+                                return false;
+                            }
+                            true
+                        }
+                    }
+                });
+                let ini_file = Ini::load_from_file(entry.path()).ok()?;
+                let general_section = ini_file.section(Some("General"))?;
+                let nb_presets = general_section.get("NbPresets")?;
+                let preset_count: u32 = nb_presets.parse().ok()?;
+                let plugin_identifier = plugin_identifier.to_string();
+                let iter = (0..preset_count).filter_map(move |i| {
+                    let section_name = format!("Preset{i}");
+                    let section = ini_file.section(Some(section_name))?;
+                    let name = section.get("Name")?;
+                    // Calculate hash. At first add info about the plug-in. Without that info,
+                    // the content could be ambiguous.
+                    let mut hasher = PersistentHasher::new();
+                    let plugin_kind_str = plugin_kind.as_ref();
+                    let plugin_info = format!("{plugin_kind_str}-{plugin_identifier}");
+                    hasher.write(plugin_info.as_bytes());
+                    // Calculate hash out of data properties ("Data", "Data_1", "Data_2", ...)
+                    let data = section.get("Data")?;
+                    hasher.write(data.as_bytes());
+                    let mut i = 1;
+                    while let Some(more_data) = section.get(format!("Data{i}")) {
+                        hasher.write(more_data.as_bytes());
+                        i += 1;
+                    }
+                    // Build entry
+                    let preset_entry = PresetEntry {
+                        preset_name: name.to_string(),
+                        plugin_kind,
+                        plugin_identifier: plugin_identifier.clone(),
+                        plugin: plugin.map(|p| p.common.core),
+                        content_hash: Some(hasher.digest_128()),
+                    };
+                    Some(preset_entry)
+                });
+                Some(iter)
+            })
+            .flatten()
+            .collect();
+        Ok(())
+    }
+
+    fn query_filter_collections(
+        &self,
+        _: &ProviderContext,
+        input: InnerBuildInput,
+        _: EnumSet<PotFilterKind>,
+    ) -> Result<InnerFilterItemCollections, Box<dyn Error>> {
+        let mut new_filters = *input.filter_input.filters;
+        new_filters.clear_this_and_dependent_filters(PotFilterKind::Bank);
+        let product_items = self
+            .query_presets_internal(&input.filter_input.with_filters(&new_filters))
+            .filter_map(|(_, entry)| Some(entry.plugin.as_ref()?.product_id))
+            .unique()
+            .map(InnerFilterItem::Product)
+            .collect();
+        let mut collections = InnerFilterItemCollections::empty();
+        collections.set(PotFilterKind::Bank, product_items);
+        Ok(collections)
+    }
+
+    fn query_presets(
+        &self,
+        ctx: &ProviderContext,
+        input: InnerBuildInput,
+    ) -> Result<Vec<SortablePresetId>, Box<dyn Error>> {
+        let preset_ids = self
+            .query_presets_internal(&input.filter_input)
+            .filter(|(_, preset_entry)| {
+                let search_input = IniSearchInput { ctx, preset_entry };
+                input.search_evaluator.matches(search_input)
+            })
+            .map(|(i, entry)| SortablePresetId::new(i as _, entry.preset_name.clone()))
+            .collect();
+        Ok(preset_ids)
+    }
+
+    fn find_preset_by_id(
+        &self,
+        ctx: &ProviderContext,
+        preset_id: InnerPresetId,
+    ) -> Option<PotPreset> {
+        let preset_entry = self.entries.get(preset_id.0 as usize)?;
+        let plugin = preset_entry
+            .plugin
+            .as_ref()
+            .and_then(|entry| ctx.plugin_db.find_plugin_by_id(&entry.id));
+        let preset = PotPreset {
+            common: PotPresetCommon {
+                persistent_id: PersistentPresetId::new(
+                    self.persistent_id().clone(),
+                    create_persistent_inner_id(preset_entry),
+                ),
+                name: preset_entry.preset_name.clone(),
+                context_name: None,
+                plugin_ids: preset_entry
+                    .plugin
+                    .as_ref()
+                    .map(|p| p.id)
+                    .into_iter()
+                    .collect(),
+                product_ids: preset_entry
+                    .plugin
+                    .as_ref()
+                    .map(|p| p.product_id)
+                    .into_iter()
+                    .collect(),
+                product_name: Some(build_product_name(preset_entry, plugin).to_string()),
+                content_hash: preset_entry.content_hash,
+                db_specific_preview_file: None,
+                is_supported: true,
+                is_available: preset_entry.plugin.is_some(),
+                metadata: Default::default(),
+            },
+            kind: PotPresetKind::Internal(InternalPotPresetKind {
+                plugin_id: preset_entry.plugin.as_ref().map(|p| p.id),
+            }),
+        };
+        Some(preset)
+    }
+}
+
+/// Example: `vst3-Surge XT.ini|My Preset`
+fn create_persistent_inner_id(preset_entry: &PresetEntry) -> PersistentInnerPresetId {
+    let plugin_kind = preset_entry.plugin_kind.as_ref();
+    let plugin_identifier = &preset_entry.plugin_identifier;
+    let escaped_preset_name = PipeEscaped(&preset_entry.preset_name);
+    let id = format!("{plugin_kind}-{plugin_identifier}.ini|{escaped_preset_name}");
+    PersistentInnerPresetId::new(id)
+}
+
+struct IniSearchInput<'a> {
+    ctx: &'a ProviderContext<'a>,
+    preset_entry: &'a PresetEntry,
+}
+
+impl SearchInput for IniSearchInput<'_> {
+    fn preset_name(&self) -> &str {
+        &self.preset_entry.preset_name
+    }
+
+    fn product_name(&self) -> Option<Cow<str>> {
+        let plugin = self
+            .preset_entry
+            .plugin
+            .as_ref()
+            .and_then(|entry| self.ctx.plugin_db.find_plugin_by_id(&entry.id));
+        Some(build_product_name(self.preset_entry, plugin))
+    }
+
+    fn file_extension(&self) -> Option<&str> {
+        None
+    }
+}
+
+fn build_product_name<'a>(preset_entry: &'a PresetEntry, plugin: Option<&Plugin>) -> Cow<'a, str> {
+    match plugin {
+        None => preset_entry.plugin_identifier.as_str().into(),
+        Some(p) => p.common.to_string().into(),
+    }
+}

plugin-reaper-relearn/pot/src/providers/mod.rs

@@ -0,0 +1,5 @@
+pub mod defaults;
+pub mod directory;
+pub mod ini;
+pub mod komplete;
+pub mod projects;

plugin-reaper-relearn/pot/src/providers/projects.rs

@@ -0,0 +1,430 @@
+use crate::provider_database::{
+    Database, InnerFilterItem, InnerFilterItemCollections, ProviderContext, SortablePresetId,
+};
+use crate::{
+    Fil, FilterInput, FilterItem, FilterItemId, InnerBuildInput, InnerPresetId,
+    PersistentDatabaseId, PersistentInnerPresetId, PersistentPresetId, PipeEscaped, PluginId,
+    PotPreset, PotPresetCommon, PotPresetKind, ProjectBasedPotPresetKind, ProjectId, SearchInput,
+};
+use std::borrow::Cow;
+
+use crate::plugins::{PluginCore, PluginDatabase};
+use base::hash_util::{
+    calculate_persistent_non_crypto_hash_one_shot, NonCryptoIndexMap, PersistentHash,
+};
+use either::Either;
+use enumset::{enum_set, EnumSet};
+use helgobox_api::persistence::PotFilterKind;
+use itertools::Itertools;
+
+use std::error::Error;
+use std::ffi::OsStr;
+
+use std::ops::Range;
+use std::path::{Path, PathBuf};
+use std::{fs, iter};
+use walkdir::WalkDir;
+
+pub struct ProjectDatabase {
+    persistent_id: PersistentDatabaseId,
+    root_dir: PathBuf,
+    name: String,
+    description: String,
+    projects: Vec<Proj>,
+    preset_entries: Vec<PresetEntry>,
+}
+
+pub struct ProjectDbConfig {
+    pub persistent_id: PersistentDatabaseId,
+    pub root_dir: PathBuf,
+    pub name: String,
+}
+
+impl ProjectDatabase {
+    pub fn open(config: ProjectDbConfig) -> Result<Self, Box<dyn Error>> {
+        if !config.root_dir.try_exists()? {
+            return Err("path to projects root directory doesn't exist".into());
+        }
+        let db = Self {
+            persistent_id: config.persistent_id,
+            name: config.name,
+            preset_entries: Default::default(),
+            description: format!("Projects in {}", config.root_dir.to_string_lossy()),
+            root_dir: config.root_dir,
+            projects: vec![],
+        };
+        Ok(db)
+    }
+
+    fn query_presets_internal<'a>(
+        &'a self,
+        filter_input: &'a FilterInput,
+    ) -> impl Iterator<Item = (usize, &'a PresetEntry)> + 'a {
+        let matches = !filter_input.filters.wants_factory_presets_only();
+        if !matches {
+            return Either::Left(iter::empty());
+        }
+        let iter = self.preset_entries.iter().enumerate().filter(|(id, e)| {
+            if let Some(FilterItemId(Some(Fil::Project(id)))) =
+                filter_input.filters.get(PotFilterKind::Project)
+            {
+                if e.project_id != id {
+                    return false;
+                }
+            }
+            let id = InnerPresetId(*id as _);
+            e.track_preset
+                .used_plugins
+                .values()
+                .any(|core| filter_input.everything_matches(Some(core), id))
+        });
+        Either::Right(iter)
+    }
+}
+
+struct PresetEntry {
+    project_id: ProjectId,
+    track_preset: TrackPreset,
+}
+
+struct Proj {
+    name: String,
+    relative_path_to_rpp: String,
+}
+
+impl Database for ProjectDatabase {
+    fn persistent_id(&self) -> &PersistentDatabaseId {
+        &self.persistent_id
+    }
+
+    fn name(&self) -> Cow<str> {
+        self.name.as_str().into()
+    }
+
+    fn description(&self) -> Cow<str> {
+        self.description.as_str().into()
+    }
+
+    fn supported_advanced_filter_kinds(&self) -> EnumSet<PotFilterKind> {
+        enum_set!(PotFilterKind::Bank | PotFilterKind::Project)
+    }
+
+    fn refresh(&mut self, ctx: &ProviderContext) -> Result<(), Box<dyn Error>> {
+        self.preset_entries = WalkDir::new(&self.root_dir)
+            .follow_links(true)
+            .into_iter()
+            .filter_map(|entry| {
+                let entry = entry.ok()?;
+                if !entry.file_type().is_file() {
+                    return None;
+                }
+                let extension = entry.path().extension()?;
+                if extension != OsStr::new("RPP") {
+                    return None;
+                }
+                let relative_path = entry.path().strip_prefix(&self.root_dir).ok()?;
+                let stem = entry.path().file_stem()?;
+                // Immediately exclude relative paths that can't be represented as valid UTF-8.
+                // Otherwise we will potentially open a can of worms (regarding persistence etc.).
+                let project = Proj {
+                    name: stem.to_str()?.to_string(),
+                    relative_path_to_rpp: relative_path.to_str()?.to_string(),
+                };
+                self.projects.push(project);
+                let project_id = ProjectId(self.projects.len() as u32 - 1);
+                process_file(entry.path(), ctx.plugin_db, project_id).ok()
+            })
+            .flatten()
+            .collect();
+        Ok(())
+    }
+
+    fn query_filter_collections(
+        &self,
+        _: &ProviderContext,
+        input: InnerBuildInput,
+        affected_kinds: EnumSet<PotFilterKind>,
+    ) -> Result<InnerFilterItemCollections, Box<dyn Error>> {
+        let mut collections = InnerFilterItemCollections::empty();
+        if affected_kinds.contains(PotFilterKind::Project) {
+            let mut new_filters = *input.filter_input.filters;
+            new_filters.clear_this_and_dependent_filters(PotFilterKind::Project);
+            let project_items = self
+                .query_presets_internal(&input.filter_input.with_filters(&new_filters))
+                .map(|(_, entry)| entry.project_id)
+                .unique()
+                .filter_map(|project_id| {
+                    let project = self.projects.get(project_id.0 as usize)?;
+                    let item = FilterItem {
+                        persistent_id: "".to_string(),
+                        id: FilterItemId(Some(Fil::Project(project_id))),
+                        parent_name: None,
+                        name: Some(project.name.clone()),
+                        icon: None,
+                        more_info: Some(project.relative_path_to_rpp.to_string()),
+                    };
+                    Some(InnerFilterItem::Unique(item))
+                })
+                .collect();
+            collections.set(PotFilterKind::Project, project_items);
+        }
+        if affected_kinds.contains(PotFilterKind::Bank) {
+            let mut new_filters = *input.filter_input.filters;
+            new_filters.clear_this_and_dependent_filters(PotFilterKind::Bank);
+            let product_items = self
+                .query_presets_internal(&input.filter_input.with_filters(&new_filters))
+                .flat_map(|(_, entry)| {
+                    entry
+                        .track_preset
+                        .used_plugins
+                        .values()
+                        .map(|core| core.product_id)
+                })
+                .unique()
+                .map(InnerFilterItem::Product)
+                .collect();
+            collections.set(PotFilterKind::Bank, product_items);
+        }
+        Ok(collections)
+    }
+
+    fn query_presets(
+        &self,
+        ctx: &ProviderContext,
+        input: InnerBuildInput,
+    ) -> Result<Vec<SortablePresetId>, Box<dyn Error>> {
+        let preset_ids = self
+            .query_presets_internal(&input.filter_input)
+            .filter(|(_, preset_entry)| {
+                let search_input = ProjectSearchInput { ctx, preset_entry };
+                input.search_evaluator.matches(search_input)
+            })
+            .map(|(i, entry)| SortablePresetId::new(i as _, entry.track_preset.preset_name.clone()))
+            .collect();
+        Ok(preset_ids)
+    }
+
+    fn find_preset_by_id(
+        &self,
+        ctx: &ProviderContext,
+        preset_id: InnerPresetId,
+    ) -> Option<PotPreset> {
+        let preset_entry = self.preset_entries.get(preset_id.0 as usize)?;
+        let project = self.projects.get(preset_entry.project_id.0 as usize)?;
+        let relative_path = PathBuf::from(&project.relative_path_to_rpp);
+        let preset = PotPreset {
+            common: PotPresetCommon {
+                persistent_id: PersistentPresetId::new(
+                    self.persistent_id().clone(),
+                    create_persistent_inner_id(project, preset_entry),
+                ),
+                name: preset_entry.track_preset.preset_name.clone(),
+                context_name: Some(project.name.clone()),
+                plugin_ids: preset_entry
+                    .track_preset
+                    .used_plugins
+                    .values()
+                    .map(|c| c.id)
+                    .collect(),
+                product_ids: preset_entry
+                    .track_preset
+                    .used_plugins
+                    .values()
+                    .map(|c| c.product_id)
+                    .collect(),
+                product_name: build_product_name(ctx, preset_entry).map(|n| n.to_string()),
+                content_hash: Some(preset_entry.track_preset.content_hash),
+                db_specific_preview_file: None,
+                is_supported: true,
+                is_available: !preset_entry.track_preset.used_plugins.is_empty(),
+                metadata: Default::default(),
+            },
+            kind: PotPresetKind::ProjectBased(ProjectBasedPotPresetKind {
+                path_to_rpp: self.root_dir.join(relative_path),
+                fx_chain_range: preset_entry.track_preset.fx_chain_range.clone(),
+            }),
+        };
+        Some(preset)
+    }
+}
+
+struct TrackPreset {
+    preset_name: String,
+    track_id: String,
+    fx_chain_range: Range<usize>,
+    used_plugins: NonCryptoIndexMap<PluginId, PluginCore>,
+    content_hash: PersistentHash,
+}
+
+fn process_file(
+    path: &Path,
+    plugin_db: &PluginDatabase,
+    project_id: ProjectId,
+) -> Result<Vec<PresetEntry>, Box<dyn Error>> {
+    let rppxml = fs::read_to_string(path)?;
+    Ok(extract_presets(&rppxml, plugin_db, project_id))
+}
+
+/// Example: `maojiao/2023-02-03-ben/2023-02-03-ben.RPP|0FF9F738-7CF6-8A49-9AEA-A9AF26DF9C46`
+fn create_persistent_inner_id(
+    project: &Proj,
+    preset_entry: &PresetEntry,
+) -> PersistentInnerPresetId {
+    let escaped_path = PipeEscaped(project.relative_path_to_rpp.as_str());
+    let id = format!("{escaped_path}|{}", preset_entry.track_preset.track_id);
+    PersistentInnerPresetId::new(id)
+}
+
+fn extract_presets(
+    rppxml: &str,
+    plugin_db: &PluginDatabase,
+    project_id: ProjectId,
+) -> Vec<PresetEntry> {
+    use rppxml_parser::*;
+    let parser = OneShotParser::new(rppxml);
+    #[derive(Debug, Default)]
+    struct P<'a> {
+        track_id: &'a str,
+        name: Option<&'a str>,
+        rfx_chain_start: Option<usize>,
+        rfx_chain_end: Option<usize>,
+        used_plugins: NonCryptoIndexMap<PluginId, PluginCore>,
+    }
+    impl<'a> P<'a> {
+        pub fn new(track_id: &'a str) -> Self {
+            Self {
+                track_id,
+                name: None,
+                rfx_chain_start: None,
+                rfx_chain_end: None,
+                used_plugins: Default::default(),
+            }
+        }
+    }
+    let mut stack: Vec<&str> = Vec::with_capacity(10);
+    let mut preset: Option<P> = None;
+    let mut presets: Vec<P> = vec![];
+    for e in parser.events() {
+        let line = e.line();
+        match e.item {
+            Item::StartTag(el) => {
+                stack.push(el.name());
+                match *stack.as_slice() {
+                    ["REAPER_PROJECT", "TRACK"] => {
+                        let track_id = el.into_values().next().unwrap_or_default();
+                        preset = Some(P::new(track_id));
+                    }
+                    ["REAPER_PROJECT", "TRACK", "FXCHAIN", _] => {
+                        if let Some(p) = &mut preset {
+                            if let Some(plugin) =
+                                plugin_db.detect_plugin_from_rxml_line(line.trim())
+                            {
+                                p.used_plugins
+                                    .insert(plugin.common.core.id, plugin.common.core);
+                            }
+                        }
+                    }
+                    _ => {}
+                }
+            }
+            Item::EndTag => {
+                match *stack.as_slice() {
+                    ["REAPER_PROJECT", "TRACK"] => {
+                        presets.extend(preset.take());
+                    }
+                    ["REAPER_PROJECT", "TRACK", "FXCHAIN"] => {
+                        if let Some(p) = &mut preset {
+                            p.rfx_chain_end = Some(e.start);
+                        }
+                    }
+                    _ => {}
+                }
+                stack.pop();
+            }
+            Item::Attribute(el) => match *stack.as_slice() {
+                ["REAPER_PROJECT", "TRACK"] => match el.name() {
+                    "NAME" => {
+                        if let Some(p) = &mut preset {
+                            let name = el.into_values().next().unwrap_or_default();
+                            p.name = Some(name)
+                        }
+                    }
+                    _ => {}
+                },
+                ["REAPER_PROJECT", "TRACK", "FXCHAIN"] => match el.name() {
+                    "BYPASS" => {
+                        if let Some(p) = &mut preset {
+                            if p.rfx_chain_start.is_none() {
+                                p.rfx_chain_start = Some(e.start);
+                            }
+                        }
+                    }
+                    _ => {}
+                },
+                _ => {}
+            },
+            Item::Content(_) => {}
+            Item::Empty => {}
+        }
+    }
+    presets
+        .into_iter()
+        .filter_map(|p| {
+            if p.used_plugins.is_empty() {
+                return None;
+            }
+            let fx_chain_range = p.rfx_chain_start?..p.rfx_chain_end?;
+            let track_id = p.track_id.strip_prefix('{')?.strip_suffix('}')?.to_string();
+            let preset_name = p.name?.to_string();
+            let content_hash = calculate_persistent_non_crypto_hash_one_shot(
+                rppxml[fx_chain_range.clone()].as_bytes(),
+            );
+            let track_preset = TrackPreset {
+                preset_name,
+                track_id,
+                fx_chain_range,
+                used_plugins: p.used_plugins,
+                content_hash,
+            };
+            let preset_entry = PresetEntry {
+                project_id,
+                track_preset,
+            };
+            Some(preset_entry)
+        })
+        .collect()
+}
+
+struct ProjectSearchInput<'a> {
+    ctx: &'a ProviderContext<'a>,
+    preset_entry: &'a PresetEntry,
+}
+
+impl SearchInput for ProjectSearchInput<'_> {
+    fn preset_name(&self) -> &str {
+        &self.preset_entry.track_preset.preset_name
+    }
+
+    fn product_name(&self) -> Option<Cow<str>> {
+        build_product_name(self.ctx, self.preset_entry)
+    }
+
+    fn file_extension(&self) -> Option<&str> {
+        None
+    }
+}
+
+fn build_product_name(
+    ctx: &ProviderContext,
+    preset_entry: &PresetEntry,
+) -> Option<Cow<'static, str>> {
+    if preset_entry.track_preset.used_plugins.len() > 1 {
+        Some("<Multiple>".into())
+    } else if let Some(first) = preset_entry.track_preset.used_plugins.values().next() {
+        ctx.plugin_db
+            .find_plugin_by_id(&first.id)
+            .map(|p| p.common.to_string().into())
+    } else {
+        None
+    }
+}

plugin-reaper-relearn/pot/src/worker.rs

@@ -0,0 +1,136 @@
+use base::Global;
+use futures::channel::oneshot;
+use once_cell::sync::Lazy;
+use std::any::Any;
+use std::collections::VecDeque;
+use std::error::Error;
+use std::future::Future;
+use tokio::runtime::Runtime;
+
+pub type PotWorkerDispatcher<C> = WorkerDispatcher<C, PotWorkerSpawner>;
+pub type MainThreadDispatcher<C> = WorkerDispatcher<C, MainThreadSpawner>;
+
+type PotWorkerResult<R> = Result<R, Box<dyn Error>>;
+
+/// Helper for easily dispatching background work from a non-asynchronous context and executing
+/// code as soon as the result of the background work is available.
+#[derive(Debug)]
+pub struct WorkerDispatcher<C, S> {
+    tasks: VecDeque<Task<C, Box<dyn Any + Send + 'static>>>,
+    spawner: S,
+}
+
+impl<C, S> WorkerDispatcher<C, S>
+where
+    S: Spawner,
+{
+    pub fn new(spawner: S) -> Self {
+        Self {
+            tasks: Default::default(),
+            spawner,
+        }
+    }
+
+    /// Checks for each background task if a result is available and if yes, executes the
+    /// corresponding result handler.
+    ///
+    /// Must be called repeatedly from the non-asynchronous code.
+    pub fn poll(&mut self, state: &mut C) {
+        // Take next task from queue. Do nothing if no task enqueued.
+        let Some(mut task) = self.tasks.pop_front() else {
+            return;
+        };
+        // Check if task has already produced some result.
+        match task.result_receiver.try_recv() {
+            // Result available. Handle it, done.
+            Ok(Some(result)) => {
+                (task.result_handler)(state, result);
+            }
+            // Result not yet available. Push task back on queue.
+            Ok(None) => {
+                self.tasks.push_back(task);
+            }
+            // Sender dropped. Discard task.
+            Err(_) => {}
+        }
+    }
+
+    /// Schedules the given work for execution by the Pot worker and registers a handler that
+    /// will be executed as soon as the work has produced a result.
+    pub fn do_in_background_and_then<R>(
+        &mut self,
+        work: impl Future<Output = R> + Send + 'static,
+        result_handler: impl FnOnce(&mut C, R) + Send + 'static,
+    ) where
+        R: Send + 'static,
+    {
+        // Create one-shot channel for transferring task result from background thread to
+        // polling thread.
+        let (sender, receiver) = oneshot::channel::<Box<dyn Any + Send + 'static>>();
+        // Combine this and the corresponding handler into a so-called task.
+        let task = Task {
+            result_receiver: receiver,
+            result_handler: Box::new(|context, result| {
+                if let Ok(result) = result.downcast::<R>() {
+                    result_handler(context, *result);
+                }
+            }),
+        };
+        // Enqueue that task for repeated polling.
+        self.tasks.push_back(task);
+        // Schedule work to be done in background.
+        self.spawner.spawn(async move {
+            // Start executing work
+            let result = work.await;
+            // Work done. Send result.
+            let _ = sender.send(Box::new(result));
+            Ok(())
+        });
+    }
+}
+
+pub fn spawn_in_pot_worker(f: impl Future<Output = PotWorkerResult<()>> + Send + 'static) {
+    POT_WORKER_RUNTIME.as_ref().unwrap().spawn(async {
+        f.await.unwrap();
+    });
+}
+
+pub trait Spawner {
+    fn spawn(&self, f: impl Future<Output = PotWorkerResult<()>> + Send + 'static);
+}
+
+#[derive(Debug)]
+pub struct PotWorkerSpawner;
+
+impl Spawner for PotWorkerSpawner {
+    fn spawn(&self, f: impl Future<Output = PotWorkerResult<()>> + Send + 'static) {
+        spawn_in_pot_worker(f);
+    }
+}
+
+#[derive(Debug)]
+pub struct MainThreadSpawner;
+
+impl Spawner for MainThreadSpawner {
+    fn spawn(&self, f: impl Future<Output = PotWorkerResult<()>> + Send + 'static) {
+        Global::future_support().spawn_in_main_thread_from_main_thread(f);
+    }
+}
+
+#[derive(derivative::Derivative)]
+#[derivative(Debug)]
+struct Task<C, R> {
+    result_receiver: oneshot::Receiver<R>,
+    #[derivative(Debug = "ignore")]
+    result_handler: ResultHandler<C, R>,
+}
+
+type ResultHandler<C, R> = Box<dyn FnOnce(&mut C, R) + Send>;
+
+static POT_WORKER_RUNTIME: Lazy<std::io::Result<Runtime>> = Lazy::new(|| {
+    tokio::runtime::Builder::new_multi_thread()
+        .enable_time()
+        .thread_name("Helgobox Pot Worker")
+        .worker_threads(1)
+        .build()
+});