feat: native folder/file picker, persistent config, and model management

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

@@ -1,18 +1,24 @@
 use std::path::Path;
 use std::process::{Child, Command};
 use std::sync::Mutex;
-use tauri::{Manager, State};
+use tauri::{AppHandle, Manager, State};
+use tauri_plugin_dialog::DialogExt;
 
 pub struct ServerState(pub Mutex<Option<Child>>);
 
-/// Query GPU info via nvidia-smi.
+// ─── GPU ──────────────────────────────────────────────────────────────────────
+
+#[derive(serde::Serialize)]
+pub struct GpuInfo {
+    pub name: String,
+    pub vram_mib: u32,
+    pub recommended_layers: i32,
+}
+
 #[tauri::command]
 fn query_gpu() -> Result<GpuInfo, String> {
     let output = Command::new("nvidia-smi")
-        .args([
-            "--query-gpu=name,memory.total",
-            "--format=csv,noheader,nounits",
-        ])
+        .args(["--query-gpu=name,memory.total", "--format=csv,noheader,nounits"])
         .output()
         .map_err(|_| "nvidia-smi not found — no NVIDIA GPU detected".to_string())?;
 
@@ -36,21 +42,11 @@ fn query_gpu() -> Result<GpuInfo, String> {
     let usable = vram_mib.saturating_sub(1024);
     let recommended_layers = (usable / 80).min(200) as i32;
 
-    Ok(GpuInfo {
-        name,
-        vram_mib,
-        recommended_layers,
-    })
+    Ok(GpuInfo { name, vram_mib, recommended_layers })
 }
 
-#[derive(serde::Serialize)]
-pub struct GpuInfo {
-    pub name: String,
-    pub vram_mib: u32,
-    pub recommended_layers: i32,
-}
+// ─── Server lifecycle ─────────────────────────────────────────────────────────
 
-/// Start the inference server with full configuration.
 #[tauri::command]
 fn start_server(
     state: State<ServerState>,
@@ -60,16 +56,11 @@ fn start_server(
     ctx_size: u32,
 ) -> Result<String, String> {
     let mut guard = state.0.lock().map_err(|e| e.to_string())?;
-
     if guard.is_some() {
         return Err("Server is already running".into());
     }
 
-    let binary = if cfg!(target_os = "windows") {
-        "localllm.exe"
-    } else {
-        "localllm"
-    };
+    let binary = if cfg!(target_os = "windows") { "localllm.exe" } else { "localllm" };
 
     let child = Command::new(binary)
         .env("LOCALLLM_MODEL", &model_path)
@@ -81,20 +72,16 @@ fn start_server(
 
     let pid = child.id();
     *guard = Some(child);
-
     Ok(format!("Server started (pid={pid}) on {addr}"))
 }
 
 #[tauri::command]
 fn stop_server(state: State<ServerState>) -> Result<String, String> {
     let mut guard = state.0.lock().map_err(|e| e.to_string())?;
-
     match guard.as_mut() {
         None => Err("Server is not running".into()),
         Some(child) => {
-            child
-                .kill()
-                .map_err(|e| format!("Failed to kill server: {e}"))?;
+            child.kill().map_err(|e| format!("Failed to kill server: {e}"))?;
             let _ = child.wait();
             *guard = None;
             Ok("Server stopped".into())
@@ -105,11 +92,15 @@ fn stop_server(state: State<ServerState>) -> Result<String, String> {
 #[tauri::command]
 fn server_status(state: State<ServerState>) -> String {
     let guard = state.0.lock().unwrap();
-    if guard.is_some() {
-        "running".into()
-    } else {
-        "stopped".into()
-    }
+    if guard.is_some() { "running".into() } else { "stopped".into() }
+}
+
+// ─── Model files ──────────────────────────────────────────────────────────────
+
+#[derive(serde::Serialize, serde::Deserialize, Clone)]
+pub struct ModelFile {
+    pub name: String,
+    pub path: String,
 }
 
 /// Scan a directory for .gguf model files.
@@ -131,16 +122,9 @@ fn scan_models(dir: String) -> Result<Vec<ModelFile>, String> {
         if p.is_file() {
             if let Some(ext) = p.extension() {
                 if ext.eq_ignore_ascii_case("gguf") {
-                    let name = p
-                        .file_name()
-                        .unwrap_or_default()
-                        .to_string_lossy()
-                        .to_string();
+                    let name = p.file_name().unwrap_or_default().to_string_lossy().to_string();
                     let full_path = p.to_string_lossy().to_string();
-                    models.push(ModelFile {
-                        name,
-                        path: full_path,
-                    });
+                    models.push(ModelFile { name, path: full_path });
                 }
             }
         }
@@ -150,13 +134,67 @@ fn scan_models(dir: String) -> Result<Vec<ModelFile>, String> {
     Ok(models)
 }
 
+/// Open a native folder picker and scan the chosen directory for .gguf files.
+/// Returns (chosen_dir, models[]).
+#[derive(serde::Serialize)]
+pub struct PickDirResult {
+    pub dir: String,
+    pub models: Vec<ModelFile>,
+}
+
+#[tauri::command]
+async fn pick_models_dir(app: AppHandle) -> Result<PickDirResult, String> {
+    let folder = app
+        .dialog()
+        .file()
+        .set_title("Select models folder")
+        .blocking_pick_folder();
+
+    match folder {
+        Some(path) => {
+            let dir = path.to_string();
+            let models = scan_models(dir.clone())?;
+            Ok(PickDirResult { dir, models })
+        }
+        None => Err("cancelled".into()),
+    }
+}
+
+/// Open a native multi-file picker filtered to .gguf files.
+/// Returns the selected ModelFile list (files in their original locations — no copy).
+#[tauri::command]
+async fn pick_model_files(app: AppHandle) -> Result<Vec<ModelFile>, String> {
+    let files = app
+        .dialog()
+        .file()
+        .set_title("Select model files")
+        .add_filter("GGUF models", &["gguf"])
+        .blocking_pick_files();
+
+    match files {
+        Some(paths) => {
+            let models: Vec<ModelFile> = paths
+                .iter()
+                .map(|p| {
+                    let path_str = p.to_string();
+                    let name = Path::new(&path_str)
+                        .file_name()
+                        .unwrap_or_default()
+                        .to_string_lossy()
+                        .to_string();
+                    ModelFile { name, path: path_str }
+                })
+                .collect();
+            Ok(models)
+        }
+        None => Err("cancelled".into()),
+    }
+}
+
 /// Copy a .gguf file into the models directory.
-/// Returns the new ModelFile on success.
 #[tauri::command]
 fn import_model(src_path: String, dest_dir: String) -> Result<ModelFile, String> {
     let src = Path::new(&src_path);
-
-    // Validate source
     if !src.exists() {
         return Err(format!("Source file not found: {src_path}"));
     }
@@ -168,7 +206,6 @@ fn import_model(src_path: String, dest_dir: String) -> Result<ModelFile, String>
         return Err("Only .gguf files are supported".into());
     }
 
-    // Ensure destination directory exists
     let dest_dir_path = Path::new(&dest_dir);
     if !dest_dir_path.exists() {
         std::fs::create_dir_all(dest_dir_path)
@@ -178,7 +215,6 @@ fn import_model(src_path: String, dest_dir: String) -> Result<ModelFile, String>
     let file_name = src.file_name().unwrap_or_default();
     let dest_path = dest_dir_path.join(file_name);
 
-    // If already in the same directory, just return it
     if src == dest_path {
         return Ok(ModelFile {
             name: file_name.to_string_lossy().to_string(),
@@ -186,7 +222,6 @@ fn import_model(src_path: String, dest_dir: String) -> Result<ModelFile, String>
         });
     }
 
-    // Copy the file
     std::fs::copy(src, &dest_path).map_err(|e| format!("Failed to copy model: {e}"))?;
 
     Ok(ModelFile {
@@ -195,24 +230,80 @@ fn import_model(src_path: String, dest_dir: String) -> Result<ModelFile, String>
     })
 }
 
-#[derive(serde::Serialize, Clone)]
-pub struct ModelFile {
-    pub name: String,
-    pub path: String,
+// ─── Persistent config ────────────────────────────────────────────────────────
+
+/// All user-configurable settings, persisted to app data dir as config.json.
+#[derive(serde::Serialize, serde::Deserialize, Clone, Default)]
+pub struct AppConfig {
+    pub models_dir: Option<String>,
+    pub model_path: Option<String>,
+    pub addr: Option<String>,
+    pub gpu_layers: Option<i32>,
+    pub ctx_size: Option<u32>,
+    pub api_key: Option<String>,
+    pub server_url: Option<String>,
+    /// Extra model paths added via file picker (not necessarily in models_dir)
+    pub extra_model_paths: Option<Vec<String>>,
 }
 
+fn config_path(app: &AppHandle) -> Result<std::path::PathBuf, String> {
+    let data_dir = app
+        .path()
+        .app_data_dir()
+        .map_err(|e| format!("Cannot resolve app data dir: {e}"))?;
+    std::fs::create_dir_all(&data_dir)
+        .map_err(|e| format!("Cannot create app data dir: {e}"))?;
+    Ok(data_dir.join("config.json"))
+}
+
+#[tauri::command]
+fn save_config(app: AppHandle, config: AppConfig) -> Result<(), String> {
+    let path = config_path(&app)?;
+    let json = serde_json::to_string_pretty(&config)
+        .map_err(|e| format!("Serialization error: {e}"))?;
+    std::fs::write(&path, json).map_err(|e| format!("Write error: {e}"))?;
+    Ok(())
+}
+
+#[tauri::command]
+fn load_config(app: AppHandle) -> Result<AppConfig, String> {
+    let path = config_path(&app)?;
+    if !path.exists() {
+        return Ok(AppConfig::default());
+    }
+    let json = std::fs::read_to_string(&path).map_err(|e| format!("Read error: {e}"))?;
+    serde_json::from_str(&json).map_err(|e| format!("Parse error: {e}"))
+}
+
+/// Returns the app data directory path (useful for debugging).
+#[tauri::command]
+fn get_app_data_dir(app: AppHandle) -> Result<String, String> {
+    app.path()
+        .app_data_dir()
+        .map(|p| p.to_string_lossy().to_string())
+        .map_err(|e| format!("Cannot resolve app data dir: {e}"))
+}
+
+// ─── App entry ────────────────────────────────────────────────────────────────
+
 #[cfg_attr(mobile, tauri::mobile_entry_point)]
 pub fn run() {
     tauri::Builder::default()
         .plugin(tauri_plugin_shell::init())
+        .plugin(tauri_plugin_dialog::init())
         .manage(ServerState(Mutex::new(None)))
         .invoke_handler(tauri::generate_handler![
             query_gpu,
             scan_models,
+            pick_models_dir,
+            pick_model_files,
             import_model,
             start_server,
             stop_server,
-            server_status
+            server_status,
+            save_config,
+            load_config,
+            get_app_data_dir,
         ])
         .setup(|app| {
             #[cfg(debug_assertions)]