Add SQLite DB service

app/src/main/java/gallery/memories/MainActivity.java

@@ -24,11 +24,11 @@ public class MainActivity extends AppCompatActivity {
         setContentView(binding.getRoot());
 
         mNativeX = new NativeX(this, binding.webview);
-        initWebview();
+        initializeWebView();
     }
 
     @SuppressLint("SetJavaScriptEnabled")
-    protected void initWebview() {
+    protected void initializeWebView() {
         binding.webview.setWebViewClient(new WebViewClient() {
             public boolean shouldOverrideUrlLoading(WebView view, WebResourceRequest request) {
                 view.loadUrl(request.getUrl().toString());

app/src/main/java/gallery/memories/service/DbService.java

@@ -0,0 +1,30 @@
+package gallery.memories.service;
+
+import android.content.Context;
+import android.database.sqlite.SQLiteDatabase;
+import android.database.sqlite.SQLiteOpenHelper;
+
+public class DbService extends SQLiteOpenHelper {
+    public DbService(Context context) {
+        super(context, "memories", null, 11);
+    }
+
+    public void onCreate(SQLiteDatabase db) {
+        // Add table for images
+        db.execSQL("CREATE TABLE images ("
+            + "id INTEGER PRIMARY KEY AUTOINCREMENT,"
+            + "local_id INTEGER,"
+            + "mtime INTEGER,"
+            + "date_taken INTEGER,"
+            + "dayid INTEGER,"
+            + "exif_uid TEXT,"
+            + "basename TEXT,"
+            + "flag INTEGER"
+            + ");");
+    }
+
+    public void onUpgrade(SQLiteDatabase database, int oldVersion, int newVersion) {
+        database.execSQL("DROP TABLE IF EXISTS images");
+        onCreate(database);
+    }
+}

app/src/main/java/gallery/memories/service/TimelineQuery.java

@@ -2,6 +2,7 @@ package gallery.memories.service;
 
 import android.content.Context;
 import android.database.Cursor;
+import android.database.sqlite.SQLiteDatabase;
 import android.net.Uri;
 import android.provider.MediaStore;
 import android.util.Log;
@@ -14,11 +15,15 @@ import java.util.ArrayList;
 import java.util.TimeZone;
 
 public class TimelineQuery {
-    final static String TAG = "QueryService";
+    final static String TAG = "TimelineQuery";
     Context mCtx;
+    SQLiteDatabase mDb;
 
     public TimelineQuery(Context context) {
         mCtx = context;
+        mDb = new DbService(context).getWritableDatabase();
+
+        fullSyncDb();
     }
 
     public JSONArray getByDayId(final long dayId) {
@@ -95,4 +100,61 @@ public class TimelineQuery {
         // Return JSON string of files
         return new JSONArray(files);
     }
+
+    protected void fullSyncDb() {
+        Uri collection = MediaStore.Images.Media.EXTERNAL_CONTENT_URI;
+
+        // Flag all images for removal
+        mDb.execSQL("UPDATE images SET flag = 1");
+
+        // Same fields as server response
+        String[] projection = new String[] {
+                MediaStore.Images.Media._ID,
+                MediaStore.Images.Media.DISPLAY_NAME,
+                MediaStore.Images.Media.DATE_TAKEN,
+                MediaStore.Images.Media.DATE_MODIFIED,
+        };
+
+        try (Cursor cursor = mCtx.getContentResolver().query(
+                collection,
+                projection,
+                null,
+                null,
+                null
+        )) {
+            int idColumn = cursor.getColumnIndexOrThrow(MediaStore.Images.Media._ID);
+            int nameColumn = cursor.getColumnIndexOrThrow(MediaStore.Images.Media.DISPLAY_NAME);
+            int dateColumn = cursor.getColumnIndexOrThrow(MediaStore.Images.Media.DATE_TAKEN);
+            int mtimeColumn = cursor.getColumnIndexOrThrow(MediaStore.Images.Media.DATE_MODIFIED);
+
+            while (cursor.moveToNext()) {
+                long id = cursor.getLong(idColumn);
+                String name = cursor.getString(nameColumn);
+                long dateTaken = cursor.getLong(dateColumn);
+                long mtime = cursor.getLong(mtimeColumn);
+
+                // Check if file with local_id and mtime already exists
+                try (Cursor c = mDb.rawQuery("SELECT id FROM images WHERE local_id = ?",
+                        new String[]{Long.toString(id)})) {
+                    if (c.getCount() > 0) {
+                        // File already exists, remove flag
+                        mDb.execSQL("UPDATE images SET flag = 0 WHERE local_id = ?", new Object[]{id});
+
+                        Log.v(TAG, "File already exists: " + id + " / " + name);
+                        continue;
+                    }
+                }
+
+                // Delete file with same local_id and insert new one
+                mDb.beginTransaction();
+                mDb.execSQL("DELETE FROM images WHERE local_id = ?", new Object[] { id });
+                mDb.execSQL("INSERT OR IGNORE INTO images (local_id, mtime, basename, dayid) VALUES (?, ?, ?, ?)",
+                        new Object[] { id, mtime, name, (dateTaken / 86400000) });
+                mDb.setTransactionSuccessful();
+                mDb.endTransaction();
+
+                Log.v(TAG, "Inserted file to local DB: " + id + " / " + name);
+            }
+        }
+    }
 }