feat: persist project selection

.living_spec/specs/functional/PERSISTENCE.md

@@ -0,0 +1,37 @@
+# Functional Spec: Persistence
+
+## 1. Scope
+The application needs to persist user preferences and session state across restarts.
+The primary use case is remembering the **Last Opened Project**.
+
+## 2. Storage Mechanism
+*   **Library:** `tauri-plugin-store`
+*   **File:** `store.json` (located in the App Data directory).
+*   **Keys:**
+    *   `last_project_path`: String (Absolute path).
+    *   (Future) `theme`: String.
+    *   (Future) `recent_projects`: Array<String>.
+
+## 3. Startup Logic
+1.  **Backend Init:**
+    *   Load `store.json`.
+    *   Read `last_project_path`.
+    *   Verify path exists and is a directory.
+    *   If valid:
+        *   Update `SessionState`.
+        *   Return "Project Loaded" status to Frontend on init.
+    *   If invalid/missing:
+        *   Clear key.
+        *   Remain in `Idle` state.
+
+## 4. Frontend Logic
+*   **On Mount:**
+    *   Call `get_current_project()` command.
+    *   If returns path -> Show Workspace.
+    *   If returns null -> Show Selection Screen.
+*   **On "Open Project":**
+    *   After successful open, save path to store.
+*   **On "Close Project":**
+    *   Clear `SessionState`.
+    *   Remove `last_project_path` from store.
+    *   Show Selection Screen.

.living_spec/specs/tech/STACK.md

@@ -81,9 +81,11 @@ To support both Remote and Local models, the system implements a `ModelProvider`
     *   `uuid`: For unique message IDs.
     *   `chrono`: For timestamps.
     *   `tauri-plugin-dialog`: Native system dialogs.
+    *   `tauri-plugin-store`: Persistent key-value storage.
 *   **JavaScript:**
     *   `@tauri-apps/api`: Tauri Bridge.
     *   `@tauri-apps/plugin-dialog`: Dialog API.
+    *   `@tauri-apps/plugin-store`: Store API.
     *   `react-markdown`: For rendering chat responses.
 
 ## Safety & Sandbox

package.json

@@ -13,6 +13,7 @@
     "@tauri-apps/api": "^2",
     "@tauri-apps/plugin-dialog": "^2.4.2",
     "@tauri-apps/plugin-opener": "^2",
+    "@tauri-apps/plugin-store": "^2.4.1",
     "react": "^19.1.0",
     "react-dom": "^19.1.0",
     "react-markdown": "^10.1.0"

pnpm-lock.yaml

@@ -17,6 +17,9 @@ importers:
       '@tauri-apps/plugin-opener':
         specifier: ^2
         version: 2.5.2
+      '@tauri-apps/plugin-store':
+        specifier: ^2.4.1
+        version: 2.4.1
       react:
         specifier: ^19.1.0
         version: 19.2.3
@@ -496,6 +499,9 @@ packages:
   '@tauri-apps/plugin-opener@2.5.2':
     resolution: {integrity: sha512-ei/yRRoCklWHImwpCcDK3VhNXx+QXM9793aQ64YxpqVF0BDuuIlXhZgiAkc15wnPVav+IbkYhmDJIv5R326Mew==}
 
+  '@tauri-apps/plugin-store@2.4.1':
+    resolution: {integrity: sha512-ckGSEzZ5Ii4Hf2D5x25Oqnm2Zf9MfDWAzR+volY0z/OOBz6aucPKEY0F649JvQ0Vupku6UJo7ugpGRDOFOunkA==}
+
   '@types/babel__core@7.20.5':
     resolution: {integrity: sha512-qoQprZvz5wQFJwMDqeseRXWv3rqMvhgpbXFfVyWhbx9X47POIA6i/+dXefEmZKoAgOaTdaIgNSMqMIU61yRyzA==}
 
@@ -1285,6 +1291,10 @@ snapshots:
     dependencies:
       '@tauri-apps/api': 2.9.1
 
+  '@tauri-apps/plugin-store@2.4.1':
+    dependencies:
+      '@tauri-apps/api': 2.9.1
+
   '@types/babel__core@7.20.5':
     dependencies:
       '@babel/parser': 7.28.5

src-tauri/Cargo.lock

@@ -2066,6 +2066,7 @@ dependencies = [
  "tauri-build",
  "tauri-plugin-dialog",
  "tauri-plugin-opener",
+ "tauri-plugin-store",
  "uuid",
  "walkdir",
 ]
@@ -4121,6 +4122,22 @@ dependencies = [
  "zbus",
 ]
 
+[[package]]
+name = "tauri-plugin-store"
+version = "2.4.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "59a77036340a97eb5bbe1b3209c31e5f27f75e6f92a52fd9dd4b211ef08bf310"
+dependencies = [
+ "dunce",
+ "serde",
+ "serde_json",
+ "tauri",
+ "tauri-plugin",
+ "thiserror 2.0.17",
+ "tokio",
+ "tracing",
+]
+
 [[package]]
 name = "tauri-runtime"
 version = "2.9.2"
@@ -4339,10 +4356,22 @@ dependencies = [
  "pin-project-lite",
  "signal-hook-registry",
  "socket2",
+ "tokio-macros",
  "tracing",
  "windows-sys 0.61.2",
 ]
 
+[[package]]
+name = "tokio-macros"
+version = "2.6.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "af407857209536a95c8e56f8231ef2c2e2aff839b22e07a1ffcbc617e9db9fa5"
+dependencies = [
+ "proc-macro2",
+ "quote",
+ "syn 2.0.111",
+]
+
 [[package]]
 name = "tokio-native-tls"
 version = "0.3.1"

src-tauri/Cargo.toml

@@ -29,4 +29,5 @@ reqwest = { version = "0.12.28", features = ["json", "blocking"] }
 uuid = { version = "1.19.0", features = ["v4", "serde"] }
 chrono = { version = "0.4.42", features = ["serde"] }
 async-trait = "0.1.89"
+tauri-plugin-store = "2.4.1"
 

src-tauri/capabilities/default.json

@@ -3,5 +3,10 @@
   "identifier": "default",
   "description": "Capability for the main window",
   "windows": ["main"],
-  "permissions": ["core:default", "opener:default", "dialog:default"]
+  "permissions": [
+    "core:default",
+    "opener:default",
+    "dialog:default",
+    "store:default"
+  ]
 }

src-tauri/src/commands/fs.rs

@@ -1,8 +1,13 @@
 use crate::state::SessionState;
 use serde::Serialize;
+use serde_json::json;
 use std::fs;
 use std::path::PathBuf;
-use tauri::State;
+use tauri::{AppHandle, State};
+use tauri_plugin_store::StoreExt;
+
+const STORE_PATH: &str = "store.json";
+const KEY_LAST_PROJECT: &str = "last_project_path";
 
 // -----------------------------------------------------------------------------
 // Helper Functions
@@ -32,7 +37,11 @@ fn resolve_path(state: &State<'_, SessionState>, relative_path: &str) -> Result<
 // -----------------------------------------------------------------------------
 
 #[tauri::command]
-pub async fn open_project(path: String, state: State<'_, SessionState>) -> Result<String, String> {
+pub async fn open_project(
+    app: AppHandle,
+    path: String,
+    state: State<'_, SessionState>,
+) -> Result<String, String> {
     let p = PathBuf::from(&path);
 
     // Validate path existence in blocking thread
@@ -49,13 +58,73 @@ pub async fn open_project(path: String, state: State<'_, SessionState>) -> Resul
     .await
     .map_err(|e| format!("Task failed: {}", e))??;
 
-    let mut root = state.project_root.lock().map_err(|e| e.to_string())?;
+    {
-    *root = Some(p.clone());
+        let mut root = state.project_root.lock().map_err(|e| e.to_string())?;
+        *root = Some(p.clone());
+    }
+
+    // Persist to store
+    let store = app
+        .store(STORE_PATH)
+        .map_err(|e| format!("Failed to access store: {}", e))?;
+    store.set(KEY_LAST_PROJECT, json!(path));
+    let _ = store.save();
 
     println!("Project opened: {:?}", p);
     Ok(path)
 }
 
+#[tauri::command]
+pub async fn close_project(app: AppHandle, state: State<'_, SessionState>) -> Result<(), String> {
+    // Clear session state
+    {
+        let mut root = state.project_root.lock().map_err(|e| e.to_string())?;
+        *root = None;
+    }
+
+    // Clear from store
+    let store = app
+        .store(STORE_PATH)
+        .map_err(|e| format!("Failed to access store: {}", e))?;
+    store.delete(KEY_LAST_PROJECT);
+    let _ = store.save();
+
+    Ok(())
+}
+
+#[tauri::command]
+pub async fn get_current_project(
+    app: AppHandle,
+    state: State<'_, SessionState>,
+) -> Result<Option<String>, String> {
+    // 1. Check in-memory state
+    {
+        let root = state.project_root.lock().map_err(|e| e.to_string())?;
+        if let Some(path) = &*root {
+            return Ok(Some(path.to_string_lossy().to_string()));
+        }
+    }
+
+    // 2. Check store
+    let store = app
+        .store(STORE_PATH)
+        .map_err(|e| format!("Failed to access store: {}", e))?;
+
+    if let Some(val) = store.get(KEY_LAST_PROJECT) {
+        if let Some(path_str) = val.as_str() {
+            let p = PathBuf::from(path_str);
+            if p.exists() && p.is_dir() {
+                // Update session state
+                let mut root = state.project_root.lock().map_err(|e| e.to_string())?;
+                *root = Some(p.clone());
+                return Ok(Some(path_str.to_string()));
+            }
+        }
+    }
+
+    Ok(None)
+}
+
 #[tauri::command]
 pub async fn read_file(path: String, state: State<'_, SessionState>) -> Result<String, String> {
     let full_path = resolve_path(&state, &path)?;

src-tauri/src/lib.rs

@@ -9,9 +9,12 @@ pub fn run() {
     tauri::Builder::default()
         .plugin(tauri_plugin_opener::init())
         .plugin(tauri_plugin_dialog::init())
+        .plugin(tauri_plugin_store::Builder::default().build())
         .manage(SessionState::default())
         .invoke_handler(tauri::generate_handler![
             commands::fs::open_project,
+            commands::fs::close_project,
+            commands::fs::get_current_project,
             commands::fs::read_file,
             commands::fs::write_file,
             commands::fs::list_directory,

src/App.tsx

@@ -1,4 +1,4 @@
-import { useState } from "react";
+import { useState, useEffect } from "react";
 import { invoke } from "@tauri-apps/api/core";
 import { open } from "@tauri-apps/plugin-dialog";
 import { Chat } from "./components/Chat";
@@ -8,6 +8,23 @@ function App() {
   const [projectPath, setProjectPath] = useState<string | null>(null);
   const [errorMsg, setErrorMsg] = useState<string | null>(null);
 
+  useEffect(() => {
+    invoke<string | null>("get_current_project")
+      .then((path) => {
+        if (path) setProjectPath(path);
+      })
+      .catch((e) => console.error(e));
+  }, []);
+
+  async function closeProject() {
+    try {
+      await invoke("close_project");
+      setProjectPath(null);
+    } catch (e) {
+      console.error(e);
+    }
+  }
+
   async function selectProject() {
     try {
       setErrorMsg(null);
@@ -57,9 +74,20 @@ function App() {
               background: "#f0f0f0",
               borderRadius: "4px",
               color: "#333",
+              display: "flex",
+              justifyContent: "space-between",
+              alignItems: "center",
             }}
           >
-            <strong>Active Project:</strong> {projectPath}
+            <span>
+              <strong>Active Project:</strong> {projectPath}
+            </span>
+            <button
+              onClick={closeProject}
+              style={{ padding: "5px 10px", fontSize: "0.9em" }}
+            >
+              Close
+            </button>
           </div>
           <hr style={{ margin: "20px 0" }} />
           <Chat />