feat(directory-access): enhance directory write handling for Android with robust permission checks

Author: cs-util

index.html

@@ -125,64 +125,49 @@ <h1>Android File System Demo</h1>
             }
         });
 
-        // 3. OPEN DIRECTORY (Fixed for Android)
+        // 3. ROBUST DIRECTORY WRITE (Android Safe)
         document.getElementById('btnDir').addEventListener('click', async () => {
             try {
                 log("Requesting directory access...");
-                const dirHandle = await window.showDirectoryPicker({
-                    mode: "readwrite"
-                });
-
-                log(`📂 Directory selected: ${dirHandle.name}`);
-
-                // 1. Verify Directory Permission
-                const options = { mode: 'readwrite' };
-                if ((await dirHandle.queryPermission(options)) !== 'granted') {
-                    if ((await dirHandle.requestPermission(options)) !== 'granted') {
-                        throw new Error("Directory write permission denied.");
-                    }
-                }
-
-                // List contents
-                const entries = [];
-                for await (const entry of dirHandle.values()) {
-                    entries.push(entry);
-                }
-                log(`Files found: ${entries.length}`);
-
-                // 2. Create/Get the File Handle
-                const fileName = 'session-log.txt';
-                let fileHandle;
+                const dirHandle = await window.showDirectoryPicker({ mode: "readwrite" });
 
+                // 1. Create the file handle (This usually works)
+                let fileHandle;
                 try {
-                    fileHandle = await dirHandle.getFileHandle(fileName, { create: true });
+                    fileHandle = await dirHandle.getFileHandle('session-log.txt', { create: true });
                 } catch (e) {
-                    throw new Error(`Could not create file handle: ${e.message}`);
+                    log("Could not create file handle.", 'error');
+                    return;
                 }
 
-                // --- THE FIX: Request Permission on the FILE handle explicitly ---
-                // Android does not always inherit permission from the parent folder.
-                if ((await fileHandle.queryPermission(options)) !== 'granted') {
-                    log("⚠️ Requesting permission for the specific file...");
-                    if ((await fileHandle.requestPermission(options)) !== 'granted') {
-                        throw new Error("File write permission denied.");
+                // 2. Try to write directly (Works on Desktop, often fails on Android)
+                try {
+                    log("Attempting direct write...");
+                    const writable = await fileHandle.createWritable();
+                    await writable.write(`Log Entry: ${new Date().toISOString()}`);
+                    await writable.close();
+                    log("✅ Success! Direct write worked.");
+                } catch (err) {
+                    // 3. Catch the specific "Read-only" error
+                    if (err.message.includes("read-only") || err.name === "NoModificationAllowedError") {
+                        log("⚠️ Direct write failed (Android Restriction).");
+                        log("🔄 Falling back to Save Picker...");
+
+                        // Fallback: Ask user to explicitly save this specific file
+                        const saveHandle = await window.showSaveFilePicker({
+                            suggestedName: 'session-log.txt',
+                        });
+                        const writable = await saveHandle.createWritable();
+                        await writable.write(`Log Entry: ${new Date().toISOString()}`);
+                        await writable.close();
+                        log("✅ Saved via fallback!");
+                    } else {
+                        throw err; // Re-throw other errors
                     }
                 }
-                // ------------------------------------------------------------------
-
-                log("Attempting to write...");
-                const writable = await fileHandle.createWritable();
-                
-                // Read existing content if possible to append (optional)
-                const timestamp = new Date().toISOString();
-                await writable.write(`\nLog Entry: ${timestamp}`);
-                await writable.close();
-
-                log(`✅ Success! Wrote to ${fileName}`);
 
             } catch (err) {
-                if (err.name === 'AbortError') log("User cancelled.");
-                else log(`Error: ${err.message}`, 'error');
+                log(`Error: ${err.message}`, 'error');
             }
         });
     </script>