/*
 * Copyright (c) 2010, 2016, Oracle and/or its affiliates. All rights reserved.
 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
 *
 * This code is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License version 2 only, as
 * published by the Free Software Foundation.  Oracle designates this
 * particular file as subject to the "Classpath" exception as provided
 * by Oracle in the LICENSE file that accompanied this code.
 *
 * This code 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
 * version 2 for more details (a copy is included in the LICENSE file that
 * accompanied this code).
 *
 * You should have received a copy of the GNU General Public License version
 * 2 along with this work; if not, write to the Free Software Foundation,
 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
 *
 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
 * or visit www.oracle.com if you need additional information or have any
 * questions.
 */
package com.sun.glass.ui;

import java.lang.annotation.Native;
import java.nio.Buffer;
import java.nio.ByteBuffer;
import java.nio.IntBuffer;
import java.nio.ByteOrder;

The object wraps the given raw pixels data.
Pixels class is NOT thread safe.
/**
 * The object wraps the given raw pixels data.
 *
 * Pixels class is NOT thread safe.
 */
public abstract class Pixels {
    
The Format specifies the native byte order of the
underlying chunk of image data.
The data may be either INTs or BYTEs depending on
the constructor used.
The format ABCD implies the following byte order:
BYTE[0] = A
BYTE[1] = B
BYTE[2] = C
BYTE[3] = D
BYTE[4] = A
...
Calling code should take care of endianness of the platform
when passing image data as ints.
/**
     * The Format specifies the native byte order of the
     * underlying chunk of image data.
     * The data may be either INTs or BYTEs depending on
     * the constructor used.
     * The format ABCD implies the following byte order:
     * BYTE[0] = A
     * BYTE[1] = B
     * BYTE[2] = C
     * BYTE[3] = D
     * BYTE[4] = A
     * ...
     * Calling code should take care of endianness of the platform
     * when passing image data as ints.
     */
    public static class Format {
        @Native public static final int BYTE_BGRA_PRE = 1;
        @Native public static final int BYTE_ARGB = 2;
    }

    public static int getNativeFormat() {
        Application.checkEventThread();
        return Application.GetApplication().staticPixels_getNativeFormat();
    }

    // Need:
    // Clipboard:
    //    public Pixels(final int width, final int height, final byte[] data)
    //
    // Robot:
    //    public Pixels(final int width, final int height, final int[] data)
    //
    // PixelUtils == Prism == GlassToolkit :
    //    public Pixels(final int width, final int height, final ByteBuffer)
    //    public Pixels(final int width, final int height, final IntBuffer)

    // The following fields are safe to be protected, since they are final
    protected final int width;
    protected final int height;
    protected final int bytesPerComponent;

    // The following fields are safe to be protected, since they are final
    protected final ByteBuffer bytes;
    protected final IntBuffer ints;

    private final float scalex;
    private final float scaley;

    protected Pixels(final int width, final int height, final ByteBuffer pixels) {
        this.width = width;
        this.height = height;
        this.bytesPerComponent = 1;
        this.bytes = pixels.slice();
        if ((this.width <= 0) || (this.height <= 0) || ((this.width * this.height * 4) > this.bytes.capacity())) {
            throw new IllegalArgumentException("Too small byte buffer size "+this.width+"x"+this.height+" ["+(this.width*this.height*4)+"] > "+this.bytes.capacity());
        }

        this.ints = null;
        this.scalex = 1.0f;
        this.scaley = 1.0f;
    }

    protected Pixels(final int width, final int height, IntBuffer pixels) {
        this.width = width;
        this.height = height;
        this.bytesPerComponent = 4;
        this.ints = pixels.slice();
        if ((this.width <= 0) || (this.height <= 0) || ((this.width * this.height) > this.ints.capacity())) {
            throw new IllegalArgumentException("Too small int buffer size "+this.width+"x"+this.height+" ["+(this.width*this.height)+"] > "+this.ints.capacity());
        }

        this.bytes = null;
        this.scalex = 1.0f;
        this.scaley = 1.0f;
    }

    protected Pixels(final int width, final int height, IntBuffer pixels, float scalex, float scaley) {
        this.width = width;
        this.height = height;
        this.bytesPerComponent = 4;
        this.ints = pixels.slice();
        if ((this.width <= 0) || (this.height <= 0) || ((this.width * this.height) > this.ints.capacity())) {
            throw new IllegalArgumentException("Too small int buffer size "+this.width+"x"+this.height+" ["+(this.width*this.height)+"] > "+this.ints.capacity());
        }

        this.bytes = null;
        this.scalex = scalex;
        this.scaley = scaley;
    }

    public final float getScaleX() {
        Application.checkEventThread();
        return this.scalex;
    }

    public final float getScaleY() {
        Application.checkEventThread();
        return this.scaley;
    }

    public final float getScaleXUnsafe() {
        return this.scalex;
    }

    public final float getScaleYUnsafe() {
        return this.scaley;
    }

    public final int getWidth() {
        Application.checkEventThread();
        return this.width;
    }

    public final int getWidthUnsafe() {
        return this.width;
    }

    public final int getHeight() {
        Application.checkEventThread();
        return this.height;
    }

    public final int getHeightUnsafe() {
        return this.height;
    }

    public final int getBytesPerComponent() {
        Application.checkEventThread();
        return this.bytesPerComponent;
    }

    /*
     * Return the original pixels buffer.
     */
    public final Buffer getPixels() {
        if (this.bytes != null) {
            this.bytes.rewind();
            return this.bytes;
        } else if (this.ints != null) {
            this.ints.rewind();
            return this.ints;
        } else {
            throw new RuntimeException("Unexpected Pixels state.");
        }
    }

    /*
     * Return a copy of pixels as bytes.
     */
    public final ByteBuffer asByteBuffer() {
        Application.checkEventThread();
        ByteBuffer bb = ByteBuffer.allocateDirect(getWidth()*getHeight()*4);
        bb.order(ByteOrder.nativeOrder());
        bb.rewind();
        asByteBuffer(bb);
        return bb;
    }

    /*
     * Copy pixels into provided byte buffer.
     * The ByteBuffer must be direct.
     */
    public final void asByteBuffer(ByteBuffer bb) {
        Application.checkEventThread();
        if (!bb.isDirect()) {
            throw new RuntimeException("Expected direct buffer.");
        } else if (bb.remaining() < (getWidth()*getHeight()*4)) {
            throw new RuntimeException("Too small buffer.");
        }
        _fillDirectByteBuffer(bb);
    }

    // This method is called from the native code to reduce the number of JNI up-calls.
    private void attachData(long ptr) {
        if (this.ints != null) {
            int[] array = !this.ints.isDirect() ? this.ints.array() : null;
            _attachInt(ptr, this.width, this.height, this.ints, array, array != null ? this.ints.arrayOffset() : 0);
        }
        if (this.bytes != null) {
            byte[] array = !this.bytes.isDirect() ? this.bytes.array() : null;
            _attachByte(ptr, this.width, this.height, this.bytes, array, array != null ? this.bytes.arrayOffset() : 0);
        }
    }

    protected abstract void _fillDirectByteBuffer(ByteBuffer bb);
    protected abstract void _attachInt(long ptr, int w, int h, IntBuffer ints, int[] array, int offset);
    protected abstract void _attachByte(long ptr, int w, int h, ByteBuffer bytes, byte[] array, int offset);

    @Override public final boolean equals(Object object) {
        Application.checkEventThread();
        boolean equals = ((object != null) && (getClass().equals(object.getClass())));
        if (equals) {
            Pixels pixels = (Pixels)object;
            equals = ((getWidth() == pixels.getWidth()) && (getHeight() == pixels.getHeight()));
            if (equals) {
                ByteBuffer b1 = asByteBuffer();
                ByteBuffer b2 = pixels.asByteBuffer();
                equals = (b1.compareTo(b2) == 0);
            }
        }
        return equals;
    }

    @Override public final int hashCode() {
        Application.checkEventThread();
        int val = getWidth();
        val = 31*val + getHeight();
        val = 17*val + asByteBuffer().hashCode();
        return val;
    }
}