added movable rooms

src/settings.rs

@@ -0,0 +1,36 @@
+use std::fs;
+use std::io;
+use std::path::PathBuf;
+
+use crate::ui::UiSettings;
+
+const APP_DIR_NAME: &str = "desktop_dungeon_generator";
+const SETTINGS_FILE_NAME: &str = "settings.json";
+
+pub fn load_settings() -> Option<UiSettings> {
+    let path = settings_path()?;
+    let content = fs::read_to_string(path).ok()?;
+    serde_json::from_str::<UiSettings>(&content).ok()
+}
+
+pub fn save_settings(settings: &UiSettings) -> io::Result<()> {
+    let path = settings_path().ok_or_else(|| {
+        io::Error::new(
+            io::ErrorKind::NotFound,
+            "No OS application data directory found",
+        )
+    })?;
+
+    if let Some(parent) = path.parent() {
+        fs::create_dir_all(parent)?;
+    }
+
+    let json = serde_json::to_string_pretty(settings)
+        .map_err(|err| io::Error::new(io::ErrorKind::InvalidData, err))?;
+    fs::write(path, json)
+}
+
+fn settings_path() -> Option<PathBuf> {
+    let base = dirs::data_local_dir().or_else(dirs::data_dir)?;
+    Some(base.join(APP_DIR_NAME).join(SETTINGS_FILE_NAME))
+}