Add TMDB metadata client and Fetch Data: real episode titles/air dates via TMDB, with a Settings modal for the API token

src-tauri/src/settings.rs

@@ -0,0 +1,61 @@
+//! Small persisted app settings - currently just the TMDB API token ("Fetch Data" needs
+//! it; everything else in the app works offline without any settings at all). Stored as
+//! plain JSON in Tauri's per-OS app config directory (e.g.
+//! `~/Library/Application Support/com.renamr.app/settings.json` on macOS,
+//! `~/.config/renamr/settings.json` on Linux) - not the original FileBot's config
+//! location, since that's Java Preferences-backed and OS/JVM-specific; this is Renamr's
+//! own, analogous location for its own settings.
+
+use serde::{Deserialize, Serialize};
+use std::fs;
+use std::path::PathBuf;
+use tauri::{AppHandle, Manager};
+
+#[derive(Debug, Default, Serialize, Deserialize)]
+struct StoredSettings {
+    #[serde(default)]
+    tmdb_token: Option<String>,
+}
+
+fn settings_path(app: &AppHandle) -> Result<PathBuf, String> {
+    let dir = app
+        .path()
+        .app_config_dir()
+        .map_err(|e| format!("couldn't resolve the app config directory: {e}"))?;
+    fs::create_dir_all(&dir).map_err(|e| format!("couldn't create {}: {e}", dir.display()))?;
+    Ok(dir.join("settings.json"))
+}
+
+fn load(app: &AppHandle) -> StoredSettings {
+    let Ok(path) = settings_path(app) else {
+        return StoredSettings::default();
+    };
+    fs::read_to_string(path)
+        .ok()
+        .and_then(|contents| serde_json::from_str(&contents).ok())
+        .unwrap_or_default()
+}
+
+fn save(app: &AppHandle, settings: &StoredSettings) -> Result<(), String> {
+    let path = settings_path(app)?;
+    let json = serde_json::to_string_pretty(settings).map_err(|e| e.to_string())?;
+    fs::write(&path, json).map_err(|e| format!("couldn't write {}: {e}", path.display()))
+}
+
+/// Returns the stored TMDB token, or `None` if nothing (or only blank text) is saved.
+pub fn tmdb_token(app: &AppHandle) -> Option<String> {
+    load(app).tmdb_token.filter(|t| !t.trim().is_empty())
+}
+
+#[tauri::command]
+pub fn get_tmdb_token(app: AppHandle) -> Option<String> {
+    tmdb_token(&app)
+}
+
+#[tauri::command]
+pub fn save_tmdb_token(app: AppHandle, token: String) -> Result<(), String> {
+    let mut settings = load(&app);
+    let trimmed = token.trim().to_string();
+    settings.tmdb_token = if trimmed.is_empty() { None } else { Some(trimmed) };
+    save(&app, &settings)
+}