/*
 * Copyright (C) 2016 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 android.view;

import android.annotation.IntDef;
import android.annotation.NonNull;
import android.annotation.Nullable;
import android.graphics.Bitmap;
import android.graphics.Rect;
import android.os.Handler;
import android.view.ViewTreeObserver.OnDrawListener;

import java.lang.annotation.Retention;
import java.lang.annotation.RetentionPolicy;

Provides a mechanisms to issue pixel copy requests to allow for copy operations from Surface to Bitmap /**
 * Provides a mechanisms to issue pixel copy requests to allow for copy
 * operations from {@link Surface} to {@link Bitmap}
 */
public final class PixelCopy {

    
@hide
/** @hide */
    @Retention(RetentionPolicy.SOURCE)
    @IntDef({SUCCESS, ERROR_UNKNOWN, ERROR_TIMEOUT, ERROR_SOURCE_NO_DATA,
        ERROR_SOURCE_INVALID, ERROR_DESTINATION_INVALID})
    public @interface CopyResultStatus {}

    
The pixel copy request succeeded /** The pixel copy request succeeded */
    public static final int SUCCESS = 0;

    
The pixel copy request failed with an unknown error. /** The pixel copy request failed with an unknown error. */
    public static final int ERROR_UNKNOWN = 1;

    
A timeout occurred while trying to acquire a buffer from the source to
copy from.
/**
     * A timeout occurred while trying to acquire a buffer from the source to
     * copy from.
     */
    public static final int ERROR_TIMEOUT = 2;

    
The source has nothing to copy from. When the source is a Surface this means that no buffers have been queued yet. Wait for the source to produce a frame and try again. /**
     * The source has nothing to copy from. When the source is a {@link Surface}
     * this means that no buffers have been queued yet. Wait for the source
     * to produce a frame and try again.
     */
    public static final int ERROR_SOURCE_NO_DATA = 3;

    
It is not possible to copy from the source. This can happen if the source
is hardware-protected or destroyed.
/**
     * It is not possible to copy from the source. This can happen if the source
     * is hardware-protected or destroyed.
     */
    public static final int ERROR_SOURCE_INVALID = 4;

    
The destination isn't a valid copy target. If the destination is a bitmap
this can occur if the bitmap is too large for the hardware to copy to.
It can also occur if the destination has been destroyed.
/**
     * The destination isn't a valid copy target. If the destination is a bitmap
     * this can occur if the bitmap is too large for the hardware to copy to.
     * It can also occur if the destination has been destroyed.
     */
    public static final int ERROR_DESTINATION_INVALID = 5;

    
Listener for observing the completion of a PixelCopy request.
/**
     * Listener for observing the completion of a PixelCopy request.
     */
    public interface OnPixelCopyFinishedListener {
        
Callback for when a pixel copy request has completed. This will be called
regardless of whether the copy succeeded or failed.
Params:
copyResult – Contains the resulting status of the copy request. This will either be PixelCopy.SUCCESS or one of the PixelCopy.ERROR_* values./**
         * Callback for when a pixel copy request has completed. This will be called
         * regardless of whether the copy succeeded or failed.
         *
         * @param copyResult Contains the resulting status of the copy request.
         * This will either be {@link PixelCopy#SUCCESS} or one of the
         * <code>PixelCopy.ERROR_*</code> values.
         */
        void onPixelCopyFinished(@CopyResultStatus int copyResult);
    }

    
Requests for the display content of a SurfaceView to be copied into a provided Bitmap. The contents of the source will be scaled to fit exactly inside the bitmap. The pixel format of the source buffer will be converted, as part of the copy, to fit the the bitmap's Config. The most recently queued buffer in the SurfaceView's Surface will be used as the source of the copy. 
Params:
source – The source from which to copy
dest – The destination of the copy. The source will be scaled to
match the width, height, and format of this bitmap.
listener – Callback for when the pixel copy request completes
listenerThread – The callback will be invoked on this Handler when
the copy is finished./**
     * Requests for the display content of a {@link SurfaceView} to be copied
     * into a provided {@link Bitmap}.
     *
     * The contents of the source will be scaled to fit exactly inside the bitmap.
     * The pixel format of the source buffer will be converted, as part of the copy,
     * to fit the the bitmap's {@link Bitmap.Config}. The most recently queued buffer
     * in the SurfaceView's Surface will be used as the source of the copy.
     *
     * @param source The source from which to copy
     * @param dest The destination of the copy. The source will be scaled to
     * match the width, height, and format of this bitmap.
     * @param listener Callback for when the pixel copy request completes
     * @param listenerThread The callback will be invoked on this Handler when
     * the copy is finished.
     */
    public static void request(@NonNull SurfaceView source, @NonNull Bitmap dest,
            @NonNull OnPixelCopyFinishedListener listener, @NonNull Handler listenerThread) {
        request(source.getHolder().getSurface(), dest, listener, listenerThread);
    }

    
Requests for the display content of a SurfaceView to be copied into a provided Bitmap. The contents of the source will be scaled to fit exactly inside the bitmap. The pixel format of the source buffer will be converted, as part of the copy, to fit the the bitmap's Config. The most recently queued buffer in the SurfaceView's Surface will be used as the source of the copy. 
Params:
source – The source from which to copy
srcRect – The area of the source to copy from. If this is null
the copy area will be the entire surface. The rect will be clamped to
the bounds of the Surface.
dest – The destination of the copy. The source will be scaled to
match the width, height, and format of this bitmap.
listener – Callback for when the pixel copy request completes
listenerThread – The callback will be invoked on this Handler when
the copy is finished./**
     * Requests for the display content of a {@link SurfaceView} to be copied
     * into a provided {@link Bitmap}.
     *
     * The contents of the source will be scaled to fit exactly inside the bitmap.
     * The pixel format of the source buffer will be converted, as part of the copy,
     * to fit the the bitmap's {@link Bitmap.Config}. The most recently queued buffer
     * in the SurfaceView's Surface will be used as the source of the copy.
     *
     * @param source The source from which to copy
     * @param srcRect The area of the source to copy from. If this is null
     * the copy area will be the entire surface. The rect will be clamped to
     * the bounds of the Surface.
     * @param dest The destination of the copy. The source will be scaled to
     * match the width, height, and format of this bitmap.
     * @param listener Callback for when the pixel copy request completes
     * @param listenerThread The callback will be invoked on this Handler when
     * the copy is finished.
     */
    public static void request(@NonNull SurfaceView source, @Nullable Rect srcRect,
            @NonNull Bitmap dest, @NonNull OnPixelCopyFinishedListener listener,
            @NonNull Handler listenerThread) {
        request(source.getHolder().getSurface(), srcRect,
                dest, listener, listenerThread);
    }

    
Requests a copy of the pixels from a Surface to be copied into a provided Bitmap. The contents of the source will be scaled to fit exactly inside the bitmap. The pixel format of the source buffer will be converted, as part of the copy, to fit the the bitmap's Config. The most recently queued buffer in the Surface will be used as the source of the copy. 
Params:
source – The source from which to copy
dest – The destination of the copy. The source will be scaled to
match the width, height, and format of this bitmap.
listener – Callback for when the pixel copy request completes
listenerThread – The callback will be invoked on this Handler when
the copy is finished./**
     * Requests a copy of the pixels from a {@link Surface} to be copied into
     * a provided {@link Bitmap}.
     *
     * The contents of the source will be scaled to fit exactly inside the bitmap.
     * The pixel format of the source buffer will be converted, as part of the copy,
     * to fit the the bitmap's {@link Bitmap.Config}. The most recently queued buffer
     * in the Surface will be used as the source of the copy.
     *
     * @param source The source from which to copy
     * @param dest The destination of the copy. The source will be scaled to
     * match the width, height, and format of this bitmap.
     * @param listener Callback for when the pixel copy request completes
     * @param listenerThread The callback will be invoked on this Handler when
     * the copy is finished.
     */
    public static void request(@NonNull Surface source, @NonNull Bitmap dest,
            @NonNull OnPixelCopyFinishedListener listener, @NonNull Handler listenerThread) {
        request(source, null, dest, listener, listenerThread);
    }

    
Requests a copy of the pixels at the provided Rect from a Surface to be copied into a provided Bitmap. The contents of the source rect will be scaled to fit exactly inside the bitmap. The pixel format of the source buffer will be converted, as part of the copy, to fit the the bitmap's Config. The most recently queued buffer in the Surface will be used as the source of the copy. 
Params:
source – The source from which to copy
srcRect – The area of the source to copy from. If this is null
the copy area will be the entire surface. The rect will be clamped to
the bounds of the Surface.
dest – The destination of the copy. The source will be scaled to
match the width, height, and format of this bitmap.
listener – Callback for when the pixel copy request completes
listenerThread – The callback will be invoked on this Handler when
the copy is finished./**
     * Requests a copy of the pixels at the provided {@link Rect} from
     * a {@link Surface} to be copied into a provided {@link Bitmap}.
     *
     * The contents of the source rect will be scaled to fit exactly inside the bitmap.
     * The pixel format of the source buffer will be converted, as part of the copy,
     * to fit the the bitmap's {@link Bitmap.Config}. The most recently queued buffer
     * in the Surface will be used as the source of the copy.
     *
     * @param source The source from which to copy
     * @param srcRect The area of the source to copy from. If this is null
     * the copy area will be the entire surface. The rect will be clamped to
     * the bounds of the Surface.
     * @param dest The destination of the copy. The source will be scaled to
     * match the width, height, and format of this bitmap.
     * @param listener Callback for when the pixel copy request completes
     * @param listenerThread The callback will be invoked on this Handler when
     * the copy is finished.
     */
    public static void request(@NonNull Surface source, @Nullable Rect srcRect,
            @NonNull Bitmap dest, @NonNull OnPixelCopyFinishedListener listener,
            @NonNull Handler listenerThread) {
        validateBitmapDest(dest);
        if (!source.isValid()) {
            throw new IllegalArgumentException("Surface isn't valid, source.isValid() == false");
        }
        if (srcRect != null && srcRect.isEmpty()) {
            throw new IllegalArgumentException("sourceRect is empty");
        }
        // TODO: Make this actually async and fast and cool and stuff
        int result = ThreadedRenderer.copySurfaceInto(source, srcRect, dest);
        listenerThread.post(new Runnable() {
            @Override
            public void run() {
                listener.onPixelCopyFinished(result);
            }
        });
    }

    
Requests a copy of the pixels from a Window to be copied into a provided Bitmap. The contents of the source will be scaled to fit exactly inside the bitmap. The pixel format of the source buffer will be converted, as part of the copy, to fit the the bitmap's Config. The most recently queued buffer in the Window's Surface will be used as the source of the copy. Note: This is limited to being able to copy from Window's with a non-null DecorView. If Window.peekDecorView() is null this throws an IllegalArgumentException. It will similarly throw an exception if the DecorView has not yet acquired a backing surface. It is recommended that OnDrawListener is used to ensure that at least one draw has happened before trying to copy from the window, otherwise either an IllegalArgumentException will be thrown or an error will be returned to the OnPixelCopyFinishedListener. 
Params:
source – The source from which to copy
dest – The destination of the copy. The source will be scaled to
match the width, height, and format of this bitmap.
listener – Callback for when the pixel copy request completes
listenerThread – The callback will be invoked on this Handler when
the copy is finished./**
     * Requests a copy of the pixels from a {@link Window} to be copied into
     * a provided {@link Bitmap}.
     *
     * The contents of the source will be scaled to fit exactly inside the bitmap.
     * The pixel format of the source buffer will be converted, as part of the copy,
     * to fit the the bitmap's {@link Bitmap.Config}. The most recently queued buffer
     * in the Window's Surface will be used as the source of the copy.
     *
     * Note: This is limited to being able to copy from Window's with a non-null
     * DecorView. If {@link Window#peekDecorView()} is null this throws an
     * {@link IllegalArgumentException}. It will similarly throw an exception
     * if the DecorView has not yet acquired a backing surface. It is recommended
     * that {@link OnDrawListener} is used to ensure that at least one draw
     * has happened before trying to copy from the window, otherwise either
     * an {@link IllegalArgumentException} will be thrown or an error will
     * be returned to the {@link OnPixelCopyFinishedListener}.
     *
     * @param source The source from which to copy
     * @param dest The destination of the copy. The source will be scaled to
     * match the width, height, and format of this bitmap.
     * @param listener Callback for when the pixel copy request completes
     * @param listenerThread The callback will be invoked on this Handler when
     * the copy is finished.
     */
    public static void request(@NonNull Window source, @NonNull Bitmap dest,
            @NonNull OnPixelCopyFinishedListener listener, @NonNull Handler listenerThread) {
        request(source, null, dest, listener, listenerThread);
    }

    
Requests a copy of the pixels at the provided Rect from a Window to be copied into a provided Bitmap. The contents of the source rect will be scaled to fit exactly inside the bitmap. The pixel format of the source buffer will be converted, as part of the copy, to fit the the bitmap's Config. The most recently queued buffer in the Window's Surface will be used as the source of the copy. Note: This is limited to being able to copy from Window's with a non-null DecorView. If Window.peekDecorView() is null this throws an IllegalArgumentException. It will similarly throw an exception if the DecorView has not yet acquired a backing surface. It is recommended that OnDrawListener is used to ensure that at least one draw has happened before trying to copy from the window, otherwise either an IllegalArgumentException will be thrown or an error will be returned to the OnPixelCopyFinishedListener. 
Params:
source – The source from which to copy
srcRect – The area of the source to copy from. If this is null
the copy area will be the entire surface. The rect will be clamped to
the bounds of the Surface.
dest – The destination of the copy. The source will be scaled to
match the width, height, and format of this bitmap.
listener – Callback for when the pixel copy request completes
listenerThread – The callback will be invoked on this Handler when
the copy is finished./**
     * Requests a copy of the pixels at the provided {@link Rect} from
     * a {@link Window} to be copied into a provided {@link Bitmap}.
     *
     * The contents of the source rect will be scaled to fit exactly inside the bitmap.
     * The pixel format of the source buffer will be converted, as part of the copy,
     * to fit the the bitmap's {@link Bitmap.Config}. The most recently queued buffer
     * in the Window's Surface will be used as the source of the copy.
     *
     * Note: This is limited to being able to copy from Window's with a non-null
     * DecorView. If {@link Window#peekDecorView()} is null this throws an
     * {@link IllegalArgumentException}. It will similarly throw an exception
     * if the DecorView has not yet acquired a backing surface. It is recommended
     * that {@link OnDrawListener} is used to ensure that at least one draw
     * has happened before trying to copy from the window, otherwise either
     * an {@link IllegalArgumentException} will be thrown or an error will
     * be returned to the {@link OnPixelCopyFinishedListener}.
     *
     * @param source The source from which to copy
     * @param srcRect The area of the source to copy from. If this is null
     * the copy area will be the entire surface. The rect will be clamped to
     * the bounds of the Surface.
     * @param dest The destination of the copy. The source will be scaled to
     * match the width, height, and format of this bitmap.
     * @param listener Callback for when the pixel copy request completes
     * @param listenerThread The callback will be invoked on this Handler when
     * the copy is finished.
     */
    public static void request(@NonNull Window source, @Nullable Rect srcRect,
            @NonNull Bitmap dest, @NonNull OnPixelCopyFinishedListener listener,
            @NonNull Handler listenerThread) {
        validateBitmapDest(dest);
        if (source == null) {
            throw new IllegalArgumentException("source is null");
        }
        if (source.peekDecorView() == null) {
            throw new IllegalArgumentException(
                    "Only able to copy windows with decor views");
        }
        Surface surface = null;
        final ViewRootImpl root = source.peekDecorView().getViewRootImpl();
        if (root != null) {
            surface = root.mSurface;
            final Rect surfaceInsets = root.mWindowAttributes.surfaceInsets;
            if (srcRect == null) {
                srcRect = new Rect(surfaceInsets.left, surfaceInsets.top,
                        root.mWidth + surfaceInsets.left, root.mHeight + surfaceInsets.top);
            } else {
                srcRect.offset(surfaceInsets.left, surfaceInsets.top);
            }
        }
        if (surface == null || !surface.isValid()) {
            throw new IllegalArgumentException(
                    "Window doesn't have a backing surface!");
        }
        request(surface, srcRect, dest, listener, listenerThread);
    }

    private static void validateBitmapDest(Bitmap bitmap) {
        // TODO: Pre-check max texture dimens if we can
        if (bitmap == null) {
            throw new IllegalArgumentException("Bitmap cannot be null");
        }
        if (bitmap.isRecycled()) {
            throw new IllegalArgumentException("Bitmap is recycled");
        }
        if (!bitmap.isMutable()) {
            throw new IllegalArgumentException("Bitmap is immutable");
        }
    }

    private PixelCopy() {}
}