Extract store invalidation detection into separate AppState

gdn-app/src-tauri/src/api.rs

@@ -1,18 +1,25 @@
 use std::sync::{Arc, Mutex};
 
-use gdn::{ids::NoteId, store::Store};
+use gdn::ids::NoteId;
 use tauri::{AppHandle, Emitter, State};
 
-use crate::types::{EventNotesStoreUpdate, Note};
+use crate::{
+    state::AppState,
+    types::{EventNotesStoreUpdate, Note},
+};
 
 // API methods are sorted alphabetically.
 
-fn update_if_required(store: &mut Store, app: &AppHandle) {
-    if let Some(store_id) = store.needs_update() {
+fn update_if_required(state: &mut AppState, app: &AppHandle) {
+    let store_id = state.store.id();
+    if state.store_last_id == Some(store_id) {
+        // No update necessary if the id hasn't changed
+        return;
+    }
+
     let payload = EventNotesStoreUpdate { store_id };
     app.emit("notes_store_update", payload).unwrap();
-        store.update();
-    }
+    state.store_last_id = Some(store_id)
 }
 
 #[tauri::command]
@@ -21,10 +28,12 @@ pub fn note_child_add(
     child_id: NoteId,
     child_position: isize,
     app: AppHandle,
-    store: State<'_, Arc<Mutex<Store>>>,
+    state: State<'_, Arc<Mutex<AppState>>>,
 ) {
-    let mut guard = store.lock().unwrap();
-    guard.add_child_at_position(id, child_id, child_position);
+    let mut guard = state.lock().unwrap();
+    guard
+        .store
+        .add_child_at_position(id, child_id, child_position);
     update_if_required(&mut guard, &app);
 }
 
@@ -36,10 +45,12 @@ pub fn note_child_move(
     to_id: NoteId,
     to_position: isize,
     app: AppHandle,
-    store: State<'_, Arc<Mutex<Store>>>,
+    state: State<'_, Arc<Mutex<AppState>>>,
 ) {
-    let mut guard = store.lock().unwrap();
-    guard.move_child_by_id_to_position(child_id, from_id, from_iteration, to_id, to_position);
+    let mut guard = state.lock().unwrap();
+    guard
+        .store
+        .move_child_by_id_to_position(child_id, from_id, from_iteration, to_id, to_position);
     update_if_required(&mut guard, &app);
 }
 
@@ -49,10 +60,12 @@ pub fn note_child_remove(
     child_id: NoteId,
     child_iteration: usize,
     app: AppHandle,
-    store: State<'_, Arc<Mutex<Store>>>,
+    state: State<'_, Arc<Mutex<AppState>>>,
 ) {
-    let mut guard = store.lock().unwrap();
-    guard.remove_child_by_id(id, child_id, child_iteration);
+    let mut guard = state.lock().unwrap();
+    guard
+        .store
+        .remove_child_by_id(id, child_id, child_iteration);
     update_if_required(&mut guard, &app);
 }
 
@@ -61,32 +74,33 @@ pub fn note_children_set(
     id: NoteId,
     children: Vec<NoteId>,
     app: AppHandle,
-    store: State<'_, Arc<Mutex<Store>>>,
+    state: State<'_, Arc<Mutex<AppState>>>,
 ) {
-    let mut guard = store.lock().unwrap();
-    guard.set_children(id, children);
+    let mut guard = state.lock().unwrap();
+    guard.store.set_children(id, children);
     update_if_required(&mut guard, &app);
 }
 
 #[tauri::command]
-pub fn note_create(text: String, app: AppHandle, store: State<'_, Arc<Mutex<Store>>>) -> Note {
-    let mut guard = store.lock().unwrap();
-    let id = guard.create(text);
+pub fn note_create(text: String, app: AppHandle, state: State<'_, Arc<Mutex<AppState>>>) -> Note {
+    let mut guard = state.lock().unwrap();
+    let id = guard.store.create(text);
+    let note = guard.store.get(id).unwrap().into();
     update_if_required(&mut guard, &app);
-    guard.get(id).unwrap().into()
+    note
 }
 
 #[tauri::command]
-pub fn note_delete(id: NoteId, app: AppHandle, store: State<'_, Arc<Mutex<Store>>>) {
-    let mut guard = store.lock().unwrap();
-    guard.delete(id);
+pub fn note_delete(id: NoteId, app: AppHandle, state: State<'_, Arc<Mutex<AppState>>>) {
+    let mut guard = state.lock().unwrap();
+    guard.store.delete(id);
     update_if_required(&mut guard, &app);
 }
 
 #[tauri::command]
-pub fn note_get(id: NoteId, store: State<'_, Arc<Mutex<Store>>>) -> Option<Note> {
-    let guard = store.lock().unwrap();
-    guard.get(id).map(|it| it.into())
+pub fn note_get(id: NoteId, state: State<'_, Arc<Mutex<AppState>>>) -> Option<Note> {
+    let guard = state.lock().unwrap();
+    guard.store.get(id).map(|it| it.into())
 }
 
 #[tauri::command]
@@ -94,16 +108,16 @@ pub fn note_text_set(
     id: NoteId,
     text: String,
     app: AppHandle,
-    store: State<'_, Arc<Mutex<Store>>>,
+    state: State<'_, Arc<Mutex<AppState>>>,
 ) {
-    let mut guard = store.lock().unwrap();
-    guard.set_text(id, text);
+    let mut guard = state.lock().unwrap();
+    guard.store.set_text(id, text);
     update_if_required(&mut guard, &app);
 }
 
 #[tauri::command]
-pub fn notes_clear(app: AppHandle, store: State<'_, Arc<Mutex<Store>>>) {
-    let mut guard = store.lock().unwrap();
-    guard.clear();
+pub fn notes_clear(app: AppHandle, state: State<'_, Arc<Mutex<AppState>>>) {
+    let mut guard = state.lock().unwrap();
+    guard.store.clear();
     update_if_required(&mut guard, &app);
 }

gdn-app/src-tauri/src/lib.rs

@@ -1,16 +1,21 @@
 use serde_json as _; // Silence unused dependency warning
 use std::sync::{Arc, Mutex};
 
-use gdn::store::Store;
+use crate::state::AppState;
 
 mod api;
+mod state;
 mod types;
 
 #[cfg_attr(mobile, tauri::mobile_entry_point)]
 pub fn run() {
+    let state = Arc::new(Mutex::new(AppState::new()));
+
+    // TODO Launch store loading task
+
     tauri::Builder::default()
         .plugin(tauri_plugin_opener::init())
-        .manage(Arc::new(Mutex::new(Store::new())))
+        .manage(state)
         .invoke_handler(tauri::generate_handler![
             api::note_child_add,
             api::note_child_move,

gdn-app/src-tauri/src/state.rs

@@ -0,0 +1,15 @@
+use gdn::store::Store;
+
+pub struct AppState {
+    pub store: Store,
+    pub store_last_id: Option<u64>,
+}
+
+impl AppState {
+    pub fn new() -> Self {
+        Self {
+            store: Store::new(),
+            store_last_id: None,
+        }
+    }
+}

gdn/src/store.rs

@@ -38,8 +38,7 @@ pub struct RichNote {
 
 #[derive(Default)]
 pub struct Store {
-    last_id: u64,
-    curr_id: u64,
+    id: u64,
     notes: HashMap<NoteId, RawNote>,
     parents: HashMap<NoteId, HashMap<NoteId, usize>>,
 }
@@ -74,16 +73,8 @@ impl Store {
         Repo { notes }
     }
 
-    pub fn needs_update(&self) -> Option<u64> {
-        if self.last_id != self.curr_id {
-            Some(self.curr_id)
-        } else {
-            None
-        }
-    }
-
-    pub fn update(&mut self) {
-        self.last_id = self.curr_id;
+    pub fn id(&self) -> u64 {
+        self.id
     }
 
     pub fn get(&self, id: NoteId) -> Option<RichNote> {
@@ -104,7 +95,7 @@ impl Store {
     }
 
     fn tick(&mut self) {
-        self.curr_id += 1;
+        self.id += 1;
     }
 
     fn make_consistent_and_tick(&mut self) {