Add blacklist option and minor code improvements

app/src/main/java/com/kabouzeid/gramophone/provider/BlacklistStore.java

@@ -0,0 +1,158 @@
+package com.kabouzeid.gramophone.provider;
+
+import android.content.ContentValues;
+import android.content.Context;
+import android.content.Intent;
+import android.database.Cursor;
+import android.database.sqlite.SQLiteDatabase;
+import android.database.sqlite.SQLiteOpenHelper;
+import android.os.Environment;
+import android.support.annotation.NonNull;
+
+import com.kabouzeid.gramophone.service.MusicService;
+import com.kabouzeid.gramophone.util.FileUtil;
+import com.kabouzeid.gramophone.util.PreferenceUtil;
+
+import java.io.File;
+import java.util.ArrayList;
+
+import hugo.weaving.DebugLog;
+
+public class BlacklistStore extends SQLiteOpenHelper {
+    private static BlacklistStore sInstance = null;
+    public static final String DATABASE_NAME = "blacklist.db";
+    private static final int VERSION = 1;
+    private Context context;
+
+    public BlacklistStore(final Context context) {
+        super(context, DATABASE_NAME, null, VERSION);
+        this.context = context;
+    }
+
+    @Override
+    public void onCreate(@NonNull final SQLiteDatabase db) {
+        db.execSQL("CREATE TABLE IF NOT EXISTS " + BlacklistStoreColumns.NAME + " ("
+                + BlacklistStoreColumns.PATH + " STRING NOT NULL);");
+    }
+
+    @Override
+    public void onUpgrade(@NonNull final SQLiteDatabase db, final int oldVersion, final int newVersion) {
+        db.execSQL("DROP TABLE IF EXISTS " + BlacklistStoreColumns.NAME);
+        onCreate(db);
+    }
+
+    @Override
+    public void onDowngrade(@NonNull SQLiteDatabase db, int oldVersion, int newVersion) {
+        db.execSQL("DROP TABLE IF EXISTS " + BlacklistStoreColumns.NAME);
+        onCreate(db);
+    }
+
+    @NonNull
+    public static synchronized BlacklistStore getInstance(@NonNull final Context context) {
+        if (sInstance == null) {
+            sInstance = new BlacklistStore(context.getApplicationContext());
+            if (!PreferenceUtil.getInstance(context).initializedBlacklist()) {
+                // blacklisted by default
+                sInstance.addPathImpl(Environment.getExternalStoragePublicDirectory(Environment.DIRECTORY_ALARMS));
+                sInstance.addPathImpl(Environment.getExternalStoragePublicDirectory(Environment.DIRECTORY_NOTIFICATIONS));
+                sInstance.addPathImpl(Environment.getExternalStoragePublicDirectory(Environment.DIRECTORY_RINGTONES));
+
+                PreferenceUtil.getInstance(context).setInitializedBlacklist();
+            }
+        }
+        return sInstance;
+    }
+
+    public void addPath(File file) {
+        addPathImpl(file);
+        notifyMediaStoreChanged();
+    }
+
+    private void addPathImpl(File file) {
+        if (file == null || contains(file)) {
+            return;
+        }
+        String path = FileUtil.safeGetCanonicalPath(file);
+
+        final SQLiteDatabase database = getWritableDatabase();
+        database.beginTransaction();
+
+        try {
+            // add the entry
+            final ContentValues values = new ContentValues(1);
+            values.put(BlacklistStoreColumns.PATH, path);
+            database.insert(BlacklistStoreColumns.NAME, null, values);
+
+            database.setTransactionSuccessful();
+        } finally {
+            database.endTransaction();
+        }
+    }
+
+    public boolean contains(File file) {
+        if (file == null) {
+            return false;
+        }
+        String path = FileUtil.safeGetCanonicalPath(file);
+
+        final SQLiteDatabase database = getReadableDatabase();
+        Cursor cursor = database.query(BlacklistStoreColumns.NAME,
+                new String[]{BlacklistStoreColumns.PATH},
+                BlacklistStoreColumns.PATH + "=?",
+                new String[]{path},
+                null, null, null, null);
+
+        boolean containsPath = cursor != null && cursor.moveToFirst();
+        if (cursor != null) {
+            cursor.close();
+        }
+        return containsPath;
+    }
+
+    public void removePath(File file) {
+        final SQLiteDatabase database = getWritableDatabase();
+        String path = FileUtil.safeGetCanonicalPath(file);
+
+        database.delete(BlacklistStoreColumns.NAME,
+                BlacklistStoreColumns.PATH + "=?",
+                new String[]{path});
+
+        notifyMediaStoreChanged();
+    }
+
+    public void clear() {
+        final SQLiteDatabase database = getWritableDatabase();
+        database.delete(BlacklistStoreColumns.NAME, null, null);
+
+        notifyMediaStoreChanged();
+    }
+
+    private void notifyMediaStoreChanged() {
+        context.sendBroadcast(new Intent(MusicService.MEDIA_STORE_CHANGED));
+    }
+
+    @NonNull
+    @DebugLog
+    public ArrayList<String> getPaths() {
+        Cursor cursor = getReadableDatabase().query(BlacklistStoreColumns.NAME,
+                new String[]{BlacklistStoreColumns.PATH},
+                null, null, null, null, null);
+
+        ArrayList<String> paths = new ArrayList<>();
+        if (cursor != null && cursor.moveToFirst()) {
+            do {
+                paths.add(cursor.getString(0));
+            } while (cursor.moveToNext());
+        }
+
+        if (cursor != null)
+            cursor.close();
+        return paths;
+    }
+
+    public interface BlacklistStoreColumns {
+        String NAME = "blacklist";
+
+        String PATH = "path";
+    }
+}