package com.javispedro.vndroid;

import android.content.Context;
import android.graphics.PixelFormat;
import android.hardware.display.DisplayManager;
import android.media.ImageReader;
import android.media.projection.MediaProjection;
import android.os.Handler;
import android.support.annotation.NonNull;
import android.util.DisplayMetrics;
import android.util.Log;
import android.view.Display;

public class ScreenMirrorGrabber extends ScreenGrabber {
    private static final String TAG = ScreenMirrorGrabber.class.getSimpleName();

    protected final MediaProjection projection;
    protected final Display realDisplay;

    protected final DisplayMetrics realDisplayMetrics;

    private float scale = 0.5f;

    public ScreenMirrorGrabber(Context context, @NonNull MediaProjection proj, @NonNull Display display) {
        super(context);
        projection = proj;
        realDisplay = display;
        realDisplayMetrics = new DisplayMetrics();
    }

    private void initDisplay() {
        realDisplay.getRealMetrics(realDisplayMetrics);

        Log.d(TAG, "real display size: " + realDisplayMetrics.widthPixels + "x" + realDisplayMetrics.heightPixels);

        int width = Math.round(realDisplayMetrics.widthPixels * scale);
        int height = Math.round(realDisplayMetrics.heightPixels * scale);
        int dpi = realDisplayMetrics.densityDpi;

        Log.d(TAG, "starting mirror display with size: " + width + "x" + height + " dpi: " + dpi);

        reader = ImageReader.newInstance(width, height, PixelFormat.RGBA_8888, MAX_IMAGES);
        reader.setOnImageAvailableListener(new ImageReaderCallback(), null);

        display = projection.createVirtualDisplay("vndroid",
                width, height, dpi,
                DisplayManager.VIRTUAL_DISPLAY_FLAG_PUBLIC | DisplayManager.VIRTUAL_DISPLAY_FLAG_AUTO_MIRROR,
                reader.getSurface(),
                new VirtualDisplayCallback(), null);
    }

    @Override
    public void start() {
        if (reader != null || display != null) {
            Log.w(TAG, "already started");
            return;
        }

        initDisplay();
    }

    @Override
    public void stop() {
        super.stop();
        projection.stop();
    }

    @Override
    public int scaleInputX(int x) {
        return Math.round(x / scale);
    }

    @Override
    public int scaleInputY(int y) {
        return Math.round(y / scale);
    }

    @Override
    public boolean hasSizeChanged() {
        DisplayMetrics metrics = new DisplayMetrics();
        realDisplay.getRealMetrics(metrics);
        return metrics.widthPixels != realDisplayMetrics.widthPixels || metrics.heightPixels != realDisplayMetrics.heightPixels;
    }

    @Override
    public void updateScreenSize() {
        final ImageReader oldReader = reader;
        reader = null;

        if (display != null) {
            display.release();
            display = null;
        }

        initDisplay();

        Log.d(TAG, "new buffers set");

        // Delay destruction of old image buffers to minimize multithread issues...
        if (oldReader != null) {
            new Handler().postDelayed(new Runnable() {
                @Override
                public void run() {
                    Log.d(TAG, "old buffers closed");
                    oldReader.close();
                }
            }, 1000);
        }
    }
}