/*
 * 				Firetweet - Twitter client for Android
 * 
 *  Copyright (C) 2012-2014 Mariotaku Lee <mariotaku.lee@gmail.com>
 * 
 *  This program is free software: you can redistribute it and/or modify
 *  it under the terms of the GNU General Public License as published by
 *  the Free Software Foundation, either version 3 of the License, or
 *  (at your option) any later version.
 * 
 *  This program is distributed in the hope that it will be useful,
 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *  GNU General Public License for more details.
 * 
 *  You should have received a copy of the GNU General Public License
 *  along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */

package org.getlantern.firetweet.nyan;

import android.content.BroadcastReceiver;
import android.content.Context;
import android.content.Intent;
import android.content.IntentFilter;
import android.content.SharedPreferences;
import android.content.SharedPreferences.OnSharedPreferenceChangeListener;
import android.content.res.Resources;
import android.os.PowerManager;
import android.service.wallpaper.WallpaperService;
import android.view.SurfaceHolder;

public class NyanWallpaperService extends WallpaperService implements NyanConstants {

    @Override
    public Engine onCreateEngine() {
        return new NyanWallpaperEngine();
    }

    private Context getContext() {
        return this;
    }

    private final class NyanWallpaperEngine extends Engine implements OnSharedPreferenceChangeListener {

        private SharedPreferences mPreferences;
        private final BroadcastReceiver mScreenReceiver = new BroadcastReceiver() {

            @Override
            public void onReceive(final Context context, final Intent intent) {
                final String action = intent.getAction();
                if (Intent.ACTION_SCREEN_ON.equals(action)) {
                    if (mHelper == null) return;
                    mHelper.start();
                } else if (Intent.ACTION_SCREEN_OFF.equals(action)) {
                    if (mHelper == null) return;
                    mHelper.stop();
                }

            }
        };

        private NyanSurfaceHelper mHelper;

        @Override
        public void onCreate(final SurfaceHolder surfaceHolder) {
            super.onCreate(surfaceHolder);
            mPreferences = getSharedPreferences(SHARED_PREFERENCES_NAME, MODE_PRIVATE);
            mPreferences.registerOnSharedPreferenceChangeListener(this);
            mHelper = new NyanSurfaceHelper(getContext());
            final IntentFilter filter = new IntentFilter();
            filter.addAction(Intent.ACTION_SCREEN_ON);
            filter.addAction(Intent.ACTION_SCREEN_OFF);
            registerReceiver(mScreenReceiver, filter);
        }

        @Override
        public void onDestroy() {
            mPreferences.unregisterOnSharedPreferenceChangeListener(this);
            unregisterReceiver(mScreenReceiver);
            super.onDestroy();
        }

        @Override
        public void onSharedPreferenceChanged(final SharedPreferences sharedPreferences, final String key) {
            if (KEY_LIVE_WALLPAPER_SCALE.equals(key)) {
                updateSurface();
            }
        }

        @Override
        public void onSurfaceCreated(final SurfaceHolder holder) {
            super.onSurfaceCreated(holder);
            holder.addCallback(mHelper);
            updateSurface();
            updateHelperState();
        }

        @Override
        public void onSurfaceDestroyed(final SurfaceHolder holder) {
            mHelper.stop();
            holder.removeCallback(mHelper);
            super.onSurfaceDestroyed(holder);
        }

        @Override
        public void onVisibilityChanged(final boolean visible) {
            super.onVisibilityChanged(visible);
            if (mHelper != null) {
                mHelper.setSkipDrawing(!visible);
            }
        }

        private void updateHelperState() {
            final PowerManager pm = (PowerManager) getSystemService(POWER_SERVICE);
            if (pm.isScreenOn()) {
                mHelper.start();
            } else {
                mHelper.stop();
            }
        }

        private void updateSurface() {
            if (mPreferences == null) return;
            final Resources res = getResources();
            final int def = res.getInteger(R.integer.default_live_wallpaper_scale);
            mHelper.setScale(mPreferences.getInt(KEY_LIVE_WALLPAPER_SCALE, def));
            updateHelperState();
        }

    }

}