/*
 * Copyright (C) 2014 The Android Open Source Project
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package com.example.android.wearable.watchface;

import android.content.BroadcastReceiver;
import android.content.Context;
import android.content.Intent;
import android.content.IntentFilter;
import android.content.res.Resources;
import android.graphics.Bitmap;
import android.graphics.Canvas;
import android.graphics.Paint;
import android.graphics.Rect;
import android.graphics.drawable.BitmapDrawable;
import android.graphics.drawable.Drawable;
import android.os.Bundle;
import android.os.Handler;
import android.os.Message;
import android.support.wearable.watchface.CanvasWatchFaceService;
import android.support.wearable.watchface.WatchFaceService;
import android.support.wearable.watchface.WatchFaceStyle;
import android.util.Log;
import android.view.SurfaceHolder;

import java.util.Calendar;
import java.util.TimeZone;
import java.util.concurrent.TimeUnit;

/**
 * Sample analog watch face with a ticking second hand. In ambient mode, the second hand isn't
 * shown. On devices with low-bit ambient mode, the hands are drawn without anti-aliasing in ambient
 * mode. The watch face is drawn with less contrast in mute mode.
 *
 * {@link SweepWatchFaceService} is similar but has a sweep second hand.
 */
public class AnalogWatchFaceService extends CanvasWatchFaceService {
    private static final String TAG = "AnalogWatchFaceService";

    /**
     * Update rate in milliseconds for interactive mode. We update once a second to advance the
     * second hand.
     */
    private static final long INTERACTIVE_UPDATE_RATE_MS = TimeUnit.SECONDS.toMillis(1);

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

    private class Engine extends CanvasWatchFaceService.Engine {
        static final int MSG_UPDATE_TIME = 0;

        static final float TWO_PI = (float) Math.PI * 2f;

        Paint mHourPaint;
        Paint mMinutePaint;
        Paint mSecondPaint;
        Paint mTickPaint;
        boolean mMute;
        Calendar mCalendar;

        /** Handler to update the time once a second in interactive mode. */
        final Handler mUpdateTimeHandler = new Handler() {
            @Override
            public void handleMessage(Message message) {
                switch (message.what) {
                    case MSG_UPDATE_TIME:
                        if (Log.isLoggable(TAG, Log.VERBOSE)) {
                            Log.v(TAG, "updating time");
                        }
                        invalidate();
                        if (shouldTimerBeRunning()) {
                            long timeMs = System.currentTimeMillis();
                            long delayMs = INTERACTIVE_UPDATE_RATE_MS
                                    - (timeMs % INTERACTIVE_UPDATE_RATE_MS);
                            mUpdateTimeHandler.sendEmptyMessageDelayed(MSG_UPDATE_TIME, delayMs);
                        }
                        break;
                }
            }
        };

        final BroadcastReceiver mTimeZoneReceiver = new BroadcastReceiver() {
            @Override
            public void onReceive(Context context, Intent intent) {
                mCalendar.setTimeZone(TimeZone.getDefault());
                invalidate();
            }
        };
        boolean mRegisteredTimeZoneReceiver = false;

        /**
         * Whether the display supports fewer bits for each color in ambient mode. When true, we
         * disable anti-aliasing in ambient mode.
         */
        boolean mLowBitAmbient;

        Bitmap mBackgroundBitmap;
        Bitmap mBackgroundScaledBitmap;

        @Override
        public void onCreate(SurfaceHolder holder) {
            if (Log.isLoggable(TAG, Log.DEBUG)) {
                Log.d(TAG, "onCreate");
            }
            super.onCreate(holder);

            setWatchFaceStyle(new WatchFaceStyle.Builder(AnalogWatchFaceService.this)
                    .setCardPeekMode(WatchFaceStyle.PEEK_MODE_SHORT)
                    .setBackgroundVisibility(WatchFaceStyle.BACKGROUND_VISIBILITY_INTERRUPTIVE)
                    .setShowSystemUiTime(false)
                    .build());

            Resources resources = AnalogWatchFaceService.this.getResources();
            Drawable backgroundDrawable = resources.getDrawable(R.drawable.bg, null /* theme */);
            mBackgroundBitmap = ((BitmapDrawable) backgroundDrawable).getBitmap();

            mHourPaint = new Paint();
            mHourPaint.setARGB(255, 200, 200, 200);
            mHourPaint.setStrokeWidth(5.f);
            mHourPaint.setAntiAlias(true);
            mHourPaint.setStrokeCap(Paint.Cap.ROUND);

            mMinutePaint = new Paint();
            mMinutePaint.setARGB(255, 200, 200, 200);
            mMinutePaint.setStrokeWidth(3.f);
            mMinutePaint.setAntiAlias(true);
            mMinutePaint.setStrokeCap(Paint.Cap.ROUND);

            mSecondPaint = new Paint();
            mSecondPaint.setARGB(255, 255, 0, 0);
            mSecondPaint.setStrokeWidth(2.f);
            mSecondPaint.setAntiAlias(true);
            mSecondPaint.setStrokeCap(Paint.Cap.ROUND);

            mTickPaint = new Paint();
            mTickPaint.setARGB(100, 255, 255, 255);
            mTickPaint.setStrokeWidth(2.f);
            mTickPaint.setAntiAlias(true);

            mCalendar = Calendar.getInstance();
        }

        @Override
        public void onDestroy() {
            mUpdateTimeHandler.removeMessages(MSG_UPDATE_TIME);
            super.onDestroy();
        }

        @Override
        public void onPropertiesChanged(Bundle properties) {
            super.onPropertiesChanged(properties);
            mLowBitAmbient = properties.getBoolean(PROPERTY_LOW_BIT_AMBIENT, false);
            if (Log.isLoggable(TAG, Log.DEBUG)) {
                Log.d(TAG, "onPropertiesChanged: low-bit ambient = " + mLowBitAmbient);
            }
        }

        @Override
        public void onTimeTick() {
            super.onTimeTick();
            if (Log.isLoggable(TAG, Log.DEBUG)) {
                Log.d(TAG, "onTimeTick: ambient = " + isInAmbientMode());
            }
            invalidate();
        }

        @Override
        public void onAmbientModeChanged(boolean inAmbientMode) {
            super.onAmbientModeChanged(inAmbientMode);
            if (Log.isLoggable(TAG, Log.DEBUG)) {
                Log.d(TAG, "onAmbientModeChanged: " + inAmbientMode);
            }
            if (mLowBitAmbient) {
                boolean antiAlias = !inAmbientMode;
                mHourPaint.setAntiAlias(antiAlias);
                mMinutePaint.setAntiAlias(antiAlias);
                mSecondPaint.setAntiAlias(antiAlias);
                mTickPaint.setAntiAlias(antiAlias);
            }
            invalidate();

            // Whether the timer should be running depends on whether we're in ambient mode (as well
            // as whether we're visible), so we may need to start or stop the timer.
            updateTimer();
        }

        @Override
        public void onInterruptionFilterChanged(int interruptionFilter) {
            super.onInterruptionFilterChanged(interruptionFilter);
            boolean inMuteMode = (interruptionFilter == WatchFaceService.INTERRUPTION_FILTER_NONE);
            if (mMute != inMuteMode) {
                mMute = inMuteMode;
                mHourPaint.setAlpha(inMuteMode ? 100 : 255);
                mMinutePaint.setAlpha(inMuteMode ? 100 : 255);
                mSecondPaint.setAlpha(inMuteMode ? 80 : 255);
                invalidate();
            }
        }

        @Override
        public void onDraw(Canvas canvas, Rect bounds) {
            mCalendar.setTimeInMillis(System.currentTimeMillis());

            int width = bounds.width();
            int height = bounds.height();

            // Draw the background, scaled to fit.
            if (mBackgroundScaledBitmap == null
                    || mBackgroundScaledBitmap.getWidth() != width
                    || mBackgroundScaledBitmap.getHeight() != height) {
                mBackgroundScaledBitmap = Bitmap.createScaledBitmap(mBackgroundBitmap,
                        width, height, true /* filter */);
            }
            canvas.drawBitmap(mBackgroundScaledBitmap, 0, 0, null);

            // Find the center. Ignore the window insets so that, on round watches with a
            // "chin", the watch face is centered on the entire screen, not just the usable
            // portion.
            float centerX = width / 2f;
            float centerY = height / 2f;

            // Draw the ticks.
            float innerTickRadius = centerX - 10;
            float outerTickRadius = centerX;
            for (int tickIndex = 0; tickIndex < 12; tickIndex++) {
                float tickRot = tickIndex * TWO_PI / 12;
                float innerX = (float) Math.sin(tickRot) * innerTickRadius;
                float innerY = (float) -Math.cos(tickRot) * innerTickRadius;
                float outerX = (float) Math.sin(tickRot) * outerTickRadius;
                float outerY = (float) -Math.cos(tickRot) * outerTickRadius;
                canvas.drawLine(centerX + innerX, centerY + innerY,
                        centerX + outerX, centerY + outerY, mTickPaint);
            }

            float seconds =
                    mCalendar.get(Calendar.SECOND) + mCalendar.get(Calendar.MILLISECOND) / 1000f;
            float secRot = seconds / 60f * TWO_PI;
            float minutes = mCalendar.get(Calendar.MINUTE) + seconds / 60f;
            float minRot = minutes / 60f * TWO_PI;
            float hours = mCalendar.get(Calendar.HOUR) + minutes / 60f;
            float hrRot = hours / 12f * TWO_PI;

            float secLength = centerX - 20;
            float minLength = centerX - 40;
            float hrLength = centerX - 80;

            if (!isInAmbientMode()) {
                float secX = (float) Math.sin(secRot) * secLength;
                float secY = (float) -Math.cos(secRot) * secLength;
                canvas.drawLine(centerX, centerY, centerX + secX, centerY + secY, mSecondPaint);
            }

            float minX = (float) Math.sin(minRot) * minLength;
            float minY = (float) -Math.cos(minRot) * minLength;
            canvas.drawLine(centerX, centerY, centerX + minX, centerY + minY, mMinutePaint);

            float hrX = (float) Math.sin(hrRot) * hrLength;
            float hrY = (float) -Math.cos(hrRot) * hrLength;
            canvas.drawLine(centerX, centerY, centerX + hrX, centerY + hrY, mHourPaint);
        }

        @Override
        public void onVisibilityChanged(boolean visible) {
            super.onVisibilityChanged(visible);
            if (Log.isLoggable(TAG, Log.DEBUG)) {
                Log.d(TAG, "onVisibilityChanged: " + visible);
            }

            if (visible) {
                registerReceiver();

                // Update time zone in case it changed while we weren't visible.
                mCalendar.setTimeZone(TimeZone.getDefault());
            } else {
                unregisterReceiver();
            }

            // Whether the timer should be running depends on whether we're visible (as well as
            // whether we're in ambient mode), so we may need to start or stop the timer.
            updateTimer();
        }

        private void registerReceiver() {
            if (mRegisteredTimeZoneReceiver) {
                return;
            }
            mRegisteredTimeZoneReceiver = true;
            IntentFilter filter = new IntentFilter(Intent.ACTION_TIMEZONE_CHANGED);
            AnalogWatchFaceService.this.registerReceiver(mTimeZoneReceiver, filter);
        }

        private void unregisterReceiver() {
            if (!mRegisteredTimeZoneReceiver) {
                return;
            }
            mRegisteredTimeZoneReceiver = false;
            AnalogWatchFaceService.this.unregisterReceiver(mTimeZoneReceiver);
        }

        /**
         * Starts the {@link #mUpdateTimeHandler} timer if it should be running and isn't currently
         * or stops it if it shouldn't be running but currently is.
         */
        private void updateTimer() {
            if (Log.isLoggable(TAG, Log.DEBUG)) {
                Log.d(TAG, "updateTimer");
            }
            mUpdateTimeHandler.removeMessages(MSG_UPDATE_TIME);
            if (shouldTimerBeRunning()) {
                mUpdateTimeHandler.sendEmptyMessage(MSG_UPDATE_TIME);
            }
        }

        /**
         * Returns whether the {@link #mUpdateTimeHandler} timer should be running. The timer should
         * only run when we're visible and in interactive mode.
         */
        private boolean shouldTimerBeRunning() {
            return isVisible() && !isInAmbientMode();
        }

    }
}
