/*

 * Copyright (c) 1997, 2008, 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.

 */

/* ****************************************************************

 ******************************************************************

 ******************************************************************

 *** COPYRIGHT (c) Eastman Kodak Company, 1997

 *** As  an unpublished  work pursuant to Title 17 of the United

 *** States Code.  All rights reserved.

 ******************************************************************

 ******************************************************************

 ******************************************************************/

package java.awt.image;

import sun.java2d.StateTrackable.State;

import static sun.java2d.StateTrackable.State.*;

import sun.java2d.StateTrackableDelegate;

import sun.awt.image.SunWritableRaster;

/**

 * This class exists to wrap one or more data arrays.  Each data array in

 * the DataBuffer is referred to as a bank.  Accessor methods for getting

 * and setting elements of the DataBuffer's banks exist with and without

 * a bank specifier.  The methods without a bank specifier use the default 0th

 * bank.  The DataBuffer can optionally take an offset per bank, so that

 * data in an existing array can be used even if the interesting data

 * doesn't start at array location zero.  Getting or setting the 0th

 * element of a bank, uses the (0+offset)th element of the array.  The

 * size field specifies how much of the data array is available for

 * use.  Size + offset for a given bank should never be greater

 * than the length of the associated data array.  The data type of

 * a data buffer indicates the type of the data array(s) and may also

 * indicate additional semantics, e.g. storing unsigned 8-bit data

 * in elements of a byte array.  The data type may be TYPE_UNDEFINED

 * or one of the types defined below.  Other types may be added in

 * the future.  Generally, an object of class DataBuffer will be cast down

 * to one of its data type specific subclasses to access data type specific

 * methods for improved performance.  Currently, the Java 2D(tm) API

 * image classes use TYPE_BYTE, TYPE_USHORT, TYPE_INT, TYPE_SHORT,

 * TYPE_FLOAT, and TYPE_DOUBLE DataBuffers to store image data.

 * @see java.awt.image.Raster

 * @see java.awt.image.SampleModel

 */

public abstract class DataBuffer {

    /** Tag for unsigned byte data. */

    public static final int TYPE_BYTE  = 0;

    /** Tag for unsigned short data. */

    public static final int TYPE_USHORT = 1;

    /** Tag for signed short data.  Placeholder for future use. */

    public static final int TYPE_SHORT = 2;

    /** Tag for int data. */

    public static final int TYPE_INT   = 3;

    /** Tag for float data.  Placeholder for future use. */

    public static final int TYPE_FLOAT  = 4;

    /** Tag for double data.  Placeholder for future use. */

    public static final int TYPE_DOUBLE  = 5;

    /** Tag for undefined data. */

    public static final int TYPE_UNDEFINED = 32;

    /** The data type of this DataBuffer. */

    protected int dataType;

    /** The number of banks in this DataBuffer. */

    protected int banks;

    /** Offset into default (first) bank from which to get the first element. */

    protected int offset;

    /** Usable size of all banks. */

    protected int size;

    /** Offsets into all banks. */

    protected int offsets[];

    /* The current StateTrackable state. */

    StateTrackableDelegate theTrackable;

    /** Size of the data types indexed by DataType tags defined above. */

    private static final int dataTypeSize[] = {8,16,16,32,32,64};

    /** Returns the size (in bits) of the data type, given a datatype tag.

      * @param type the value of one of the defined datatype tags

      * @return the size of the data type

      * @throws IllegalArgumentException if <code>type</code> is less than

      *         zero or greater than {@link #TYPE_DOUBLE}

      */

    public static int getDataTypeSize(int type) {

        if (type < TYPE_BYTE || type > TYPE_DOUBLE) {

            throw new IllegalArgumentException("Unknown data type "+type);

        }

        return dataTypeSize[type];

    }

    /**

     *  Constructs a DataBuffer containing one bank of the specified

     *  data type and size.

     *

     *  @param dataType the data type of this <code>DataBuffer</code>

     *  @param size the size of the banks

     */

    protected DataBuffer(int dataType, int size) {

        this(UNTRACKABLE, dataType, size);

    }

    /**

     *  Constructs a DataBuffer containing one bank of the specified

     *  data type and size with the indicated initial {@link State State}.

     *

     *  @param initialState the initial {@link State State} state of the data

     *  @param dataType the data type of this <code>DataBuffer</code>

     *  @param size the size of the banks

     *  @since 1.7

     */

    DataBuffer(State initialState,

               int dataType, int size)

    {

        this.theTrackable = StateTrackableDelegate.createInstance(initialState);

        this.dataType = dataType;

        this.banks = 1;

        this.size = size;

        this.offset = 0;

        this.offsets = new int[1];  // init to 0 by new

    }

    /**

     *  Constructs a DataBuffer containing the specified number of

     *  banks.  Each bank has the specified size and an offset of 0.

     *

     *  @param dataType the data type of this <code>DataBuffer</code>

     *  @param size the size of the banks

     *  @param numBanks the number of banks in this

     *         <code>DataBuffer</code>

     */

    protected DataBuffer(int dataType, int size, int numBanks) {

        this(UNTRACKABLE, dataType, size, numBanks);

    }

    /**

     *  Constructs a DataBuffer containing the specified number of

     *  banks with the indicated initial {@link State State}.

     *  Each bank has the specified size and an offset of 0.

     *

     *  @param initialState the initial {@link State State} state of the data

     *  @param dataType the data type of this <code>DataBuffer</code>

     *  @param size the size of the banks

     *  @param numBanks the number of banks in this

     *         <code>DataBuffer</code>

     *  @since 1.7

     */

    DataBuffer(State initialState,

               int dataType, int size, int numBanks)

    {

        this.theTrackable = StateTrackableDelegate.createInstance(initialState);

        this.dataType = dataType;

        this.banks = numBanks;

        this.size = size;

        this.offset = 0;

        this.offsets = new int[banks]; // init to 0 by new

    }

    /**

     *  Constructs a DataBuffer that contains the specified number

     *  of banks.  Each bank has the specified datatype, size and offset.

     *

     *  @param dataType the data type of this <code>DataBuffer</code>

     *  @param size the size of the banks

     *  @param numBanks the number of banks in this

     *         <code>DataBuffer</code>

     *  @param offset the offset for each bank

     */

    protected DataBuffer(int dataType, int size, int numBanks, int offset) {

        this(UNTRACKABLE, dataType, size, numBanks, offset);

    }

    /**

     *  Constructs a DataBuffer that contains the specified number

     *  of banks with the indicated initial {@link State State}.

     *  Each bank has the specified datatype, size and offset.

     *

     *  @param initialState the initial {@link State State} state of the data

     *  @param dataType the data type of this <code>DataBuffer</code>

     *  @param size the size of the banks

     *  @param numBanks the number of banks in this

     *         <code>DataBuffer</code>

     *  @param offset the offset for each bank

     *  @since 1.7

     */

    DataBuffer(State initialState,

               int dataType, int size, int numBanks, int offset)

    {

        this.theTrackable = StateTrackableDelegate.createInstance(initialState);

        this.dataType = dataType;

        this.banks = numBanks;

        this.size = size;

        this.offset = offset;

        this.offsets = new int[numBanks];

        for (int i = 0; i < numBanks; i++) {

            this.offsets[i] = offset;

        }

    }

    /**

     *  Constructs a DataBuffer which contains the specified number

     *  of banks.  Each bank has the specified datatype and size.  The

     *  offset for each bank is specified by its respective entry in

     *  the offsets array.

     *

     *  @param dataType the data type of this <code>DataBuffer</code>

     *  @param size the size of the banks

     *  @param numBanks the number of banks in this

     *         <code>DataBuffer</code>

     *  @param offsets an array containing an offset for each bank.

     *  @throws ArrayIndexOutOfBoundsException if <code>numBanks</code>

     *          does not equal the length of <code>offsets</code>

     */

    protected DataBuffer(int dataType, int size, int numBanks, int offsets[]) {

        this(UNTRACKABLE, dataType, size, numBanks, offsets);

    }

    /**

     *  Constructs a DataBuffer which contains the specified number

     *  of banks with the indicated initial {@link State State}.

     *  Each bank has the specified datatype and size.  The

     *  offset for each bank is specified by its respective entry in

     *  the offsets array.

     *

     *  @param initialState the initial {@link State State} state of the data

     *  @param dataType the data type of this <code>DataBuffer</code>

     *  @param size the size of the banks

     *  @param numBanks the number of banks in this

     *         <code>DataBuffer</code>

     *  @param offsets an array containing an offset for each bank.

     *  @throws ArrayIndexOutOfBoundsException if <code>numBanks</code>

     *          does not equal the length of <code>offsets</code>

     *  @since 1.7

     */

    DataBuffer(State initialState,

               int dataType, int size, int numBanks, int offsets[])

    {

        if (numBanks != offsets.length) {

            throw new ArrayIndexOutOfBoundsException("Number of banks" +

                 " does not match number of bank offsets");

        }

        this.theTrackable = StateTrackableDelegate.createInstance(initialState);

        this.dataType = dataType;

        this.banks = numBanks;

        this.size = size;

        this.offset = offsets[0];

        this.offsets = (int[])offsets.clone();

    }

    /**  Returns the data type of this DataBuffer.

     *   @return the data type of this <code>DataBuffer</code>.

     */

    public int getDataType() {

        return dataType;

    }

    /**  Returns the size (in array elements) of all banks.

     *   @return the size of all banks.

     */

    public int getSize() {

        return size;

    }

    /** Returns the offset of the default bank in array elements.

     *  @return the offset of the default bank.

     */

    public int getOffset() {

        return offset;

    }

    /** Returns the offsets (in array elements) of all the banks.

     *  @return the offsets of all banks.

     */

    public int[] getOffsets() {

        return (int[])offsets.clone();

    }

    /** Returns the number of banks in this DataBuffer.

     *  @return the number of banks.

     */

    public int getNumBanks() {

        return banks;

    }

    /**

     * Returns the requested data array element from the first (default) bank

     * as an integer.

     * @param i the index of the requested data array element

     * @return the data array element at the specified index.

     * @see #setElem(int, int)

     * @see #setElem(int, int, int)

     */

    public int getElem(int i) {

        return getElem(0,i);

    }

    /**

     * Returns the requested data array element from the specified bank

     * as an integer.

     * @param bank the specified bank

     * @param i the index of the requested data array element

     * @return the data array element at the specified index from the

     *         specified bank at the specified index.

     * @see #setElem(int, int)

     * @see #setElem(int, int, int)

     */

    public abstract int getElem(int bank, int i);

    /**

     * Sets the requested data array element in the first (default) bank

     * from the given integer.

     * @param i the specified index into the data array

     * @param val the data to set the element at the specified index in

     * the data array

     * @see #getElem(int)

     * @see #getElem(int, int)

     */

    public void  setElem(int i, int val) {

        setElem(0,i,val);

    }

    /**

     * Sets the requested data array element in the specified bank

     * from the given integer.

     * @param bank the specified bank

     * @param i the specified index into the data array

     * @param val  the data to set the element in the specified bank

     * at the specified index in the data array

     * @see #getElem(int)

     * @see #getElem(int, int)

     */

    public abstract void setElem(int bank, int i, int val);

    /**

     * Returns the requested data array element from the first (default) bank

     * as a float.  The implementation in this class is to cast getElem(i)

     * to a float.  Subclasses may override this method if another

     * implementation is needed.

     * @param i the index of the requested data array element

     * @return a float value representing the data array element at the

     *  specified index.

     * @see #setElemFloat(int, float)

     * @see #setElemFloat(int, int, float)

     */

    public float getElemFloat(int i) {

        return (float)getElem(i);

    }

    /**

     * Returns the requested data array element from the specified bank

     * as a float.  The implementation in this class is to cast

     * {@link #getElem(int, int)}

     * to a float.  Subclasses can override this method if another

     * implementation is needed.

     * @param bank the specified bank

     * @param i the index of the requested data array element

     * @return a float value representing the data array element from the

     * specified bank at the specified index.

     * @see #setElemFloat(int, float)

     * @see #setElemFloat(int, int, float)

     */

    public float getElemFloat(int bank, int i) {

        return (float)getElem(bank,i);

    }

    /**

     * Sets the requested data array element in the first (default) bank

     * from the given float.  The implementation in this class is to cast

     * val to an int and call {@link #setElem(int, int)}.  Subclasses

     * can override this method if another implementation is needed.

     * @param i the specified index

     * @param val the value to set the element at the specified index in

     * the data array

     * @see #getElemFloat(int)

     * @see #getElemFloat(int, int)

     */

    public void setElemFloat(int i, float val) {

        setElem(i,(int)val);

    }

    /**

     * Sets the requested data array element in the specified bank

     * from the given float.  The implementation in this class is to cast

     * val to an int and call {@link #setElem(int, int)}.  Subclasses can

     * override this method if another implementation is needed.

     * @param bank the specified bank

     * @param i the specified index

     * @param val the value to set the element in the specified bank at

     * the specified index in the data array

     * @see #getElemFloat(int)

     * @see #getElemFloat(int, int)

     */

    public void setElemFloat(int bank, int i, float val) {

        setElem(bank,i,(int)val);

    }

    /**

     * Returns the requested data array element from the first (default) bank

     * as a double.  The implementation in this class is to cast

     * {@link #getElem(int)}

     * to a double.  Subclasses can override this method if another

     * implementation is needed.

     * @param i the specified index

     * @return a double value representing the element at the specified

     * index in the data array.

     * @see #setElemDouble(int, double)

     * @see #setElemDouble(int, int, double)

     */

    public double getElemDouble(int i) {

        return (double)getElem(i);

    }

    /**

     * Returns the requested data array element from the specified bank as

     * a double.  The implementation in this class is to cast getElem(bank, i)

     * to a double.  Subclasses may override this method if another

     * implementation is needed.

     * @param bank the specified bank

     * @param i the specified index

     * @return a double value representing the element from the specified

     * bank at the specified index in the data array.

     * @see #setElemDouble(int, double)

     * @see #setElemDouble(int, int, double)

     */

    public double getElemDouble(int bank, int i) {

        return (double)getElem(bank,i);

    }

    /**

     * Sets the requested data array element in the first (default) bank

     * from the given double.  The implementation in this class is to cast

     * val to an int and call {@link #setElem(int, int)}.  Subclasses can

     * override this method if another implementation is needed.

     * @param i the specified index

     * @param val the value to set the element at the specified index

     * in the data array

     * @see #getElemDouble(int)

     * @see #getElemDouble(int, int)

     */

    public void setElemDouble(int i, double val) {

        setElem(i,(int)val);

    }

    /**

     * Sets the requested data array element in the specified bank

     * from the given double.  The implementation in this class is to cast

     * val to an int and call {@link #setElem(int, int)}.  Subclasses can

     * override this method if another implementation is needed.

     * @param bank the specified bank

     * @param i the specified index

     * @param val the value to set the element in the specified bank

     * at the specified index of the data array

     * @see #getElemDouble(int)

     * @see #getElemDouble(int, int)

     */

    public void setElemDouble(int bank, int i, double val) {

        setElem(bank,i,(int)val);

    }

    static int[] toIntArray(Object obj) {

        if (obj instanceof int[]) {

            return (int[])obj;

        } else if (obj == null) {

            return null;

        } else if (obj instanceof short[]) {

            short sdata[] = (short[])obj;

            int idata[] = new int[sdata.length];

            for (int i = 0; i < sdata.length; i++) {

                idata[i] = (int)sdata[i] & 0xffff;

            }

            return idata;

        } else if (obj instanceof byte[]) {

            byte bdata[] = (byte[])obj;

            int idata[] = new int[bdata.length];

            for (int i = 0; i < bdata.length; i++) {

                idata[i] = 0xff & (int)bdata[i];

            }

            return idata;

        }

        return null;

    }

    static {

        SunWritableRaster.setDataStealer(new SunWritableRaster.DataStealer() {

            public byte[] getData(DataBufferByte dbb, int bank) {

                return dbb.bankdata[bank];

            }

            public short[] getData(DataBufferUShort dbus, int bank) {

                return dbus.bankdata[bank];