/*

 * 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

 * particular file as subject to the "Classpath" exception as provided

 *

 * 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.

 *

 */

package sun.io;

import sun.nio.cs.Surrogate;

import sun.nio.cs.ext.DoubleByte;

import static sun.nio.cs.CharsetMapping.*;

public abstract class CharToByteDBCS_EBCDIC extends CharToByteConverter

{

    private static final int SBCS = 0;

    private static final int DBCS = 1;

    private static final byte SO = 0x0e;

    private static final byte SI = 0x0f;

    private int  currentState;

    private char highHalfZoneCode;

    private byte[] outputByte = new byte[2];

    private DoubleByte.Encoder enc;

    public CharToByteDBCS_EBCDIC(DoubleByte.Encoder enc) {

        super();

        highHalfZoneCode = 0;

        currentState = SBCS;

        this.enc = enc;

    }

    int encodeChar(char c) {

        return enc.encodeChar(c);

    }

    /**

      * flush out any residual data and reset the buffer state

      */

    public int flush(byte [] output, int outStart, int outEnd)

        throws MalformedInputException, ConversionBufferFullException

    {

        int bytesOut = 0;

        if (highHalfZoneCode != 0) {

            reset();

            badInputLength = 0;

            throw new MalformedInputException();

        }

        if (currentState == DBCS) {

          if (outStart >= outEnd)

            throw new ConversionBufferFullException();

          output[outStart] = SI;

          bytesOut++;

        }

        reset();

        return bytesOut;

    }

    /**

     * Character conversion

     */

    public int convert(char[] input, int inOff, int inEnd,

                       byte[] output, int outOff, int outEnd)

        throws UnknownCharacterException, MalformedInputException,

               ConversionBufferFullException

    {

        char    inputChar;

        int     inputSize;

        byteOff = outOff;

        charOff = inOff;

        while(charOff < inEnd) {

           int   index;

           int   theBytes;

           int   spaceNeeded;

           if (highHalfZoneCode == 0) {

              inputChar = input[charOff];

              inputSize = 1;

           } else {

              inputChar = highHalfZoneCode;

              inputSize = 0;

              highHalfZoneCode = 0;

           }

           // Is this a high surrogate?

           if (Character.isHighSurrogate(inputChar)) {

              // Is this the last character of the input?

              if (charOff + inputSize >= inEnd) {

                 highHalfZoneCode = inputChar;

                 charOff += inputSize;

                 break;

              }

              // Is there a low surrogate following?

              inputChar = input[charOff + inputSize];

              if (Character.isLowSurrogate(inputChar)) {

                 // We have a valid surrogate pair.  Too bad we don't do

                 // surrogates.  Is substitution enabled?

                 if (subMode) {

                    if (subBytes.length == 1) {

                       outputByte[0] = 0x00;

                       outputByte[1] = subBytes[0];

                    }

                    else {

                       outputByte[0] = subBytes[0];

                       outputByte[1] = subBytes[1];

                    }

                    inputSize++;

                 } else {

                    badInputLength = 2;

                    throw new UnknownCharacterException();

                 }

              } else {

                 // We have a malformed surrogate pair

                 badInputLength = 1;

                 throw new MalformedInputException();

              }

           }

           // Is this an unaccompanied low surrogate?

           else if (Character.isLowSurrogate(inputChar)) {

               badInputLength = 1;

               throw new MalformedInputException();

           } else {

               // We have a valid character, get the bytes for it

               theBytes = encodeChar(inputChar);

               if (theBytes == UNMAPPABLE_ENCODING) {

                   // if there was no mapping - look for substitution characters

                   if (subMode) {

                       if (subBytes.length == 1) {

                           outputByte[0] = 0x00;

                           outputByte[1] = subBytes[0];

                       } else {

                           outputByte[0] = subBytes[0];

                           outputByte[1] = subBytes[1];

                       }

                   } else {

                       badInputLength = 1;

                       throw new UnknownCharacterException();

                   }

               } else {

                   outputByte[0] = (byte)((theBytes & 0x0000ff00)>>8);

                   outputByte[1] = (byte)(theBytes & 0x000000ff);

               }

           }

           //Set the output buffer into the correct state

           if (currentState == DBCS && outputByte[0] == 0x00) {

              if (byteOff >= outEnd)

                 throw new ConversionBufferFullException();

              currentState = SBCS;

              output[byteOff++] = SI;

           } else

              if (currentState == SBCS && outputByte[0] != 0x00) {

                 if (byteOff >= outEnd) {

                    throw new ConversionBufferFullException();

                 }

                 currentState = DBCS;

                 output[byteOff++] = SO;

              }

           if (currentState == DBCS)

              spaceNeeded = 2;

           else

              spaceNeeded = 1;

           if (byteOff + spaceNeeded > outEnd) {

              throw new ConversionBufferFullException();

           }

           if (currentState == SBCS)

              output[byteOff++] = outputByte[1];

           else {

              output[byteOff++] = outputByte[0];

              output[byteOff++] = outputByte[1];

           }

           charOff += inputSize;

        }

        return byteOff - outOff;

    }

    /**

     * Resets converter to its initial state.

     */

    public void reset() {

       charOff = byteOff = 0;

       highHalfZoneCode = 0;

       currentState = SBCS;

    }

    /**

     * Returns the maximum number of bytes needed to convert a char.

     */

    public int getMaxBytesPerChar() {

       return 4;    //Fixed with bug 4199599 so tests would pass.

    }

    /**

     * Sets the substitution bytes to use when the converter is in

     * substitution mode.  The given bytes should represent a valid

     * character in the target character encoding.

     */

    public void setSubstitutionBytes( byte[] newSubBytes )

       throws IllegalArgumentException

    {

       if( newSubBytes.length > 2 || newSubBytes.length == 0) {

           throw new IllegalArgumentException();

       }

       subBytes = new byte[ newSubBytes.length ];

       System.arraycopy( newSubBytes, 0, subBytes, 0, newSubBytes.length );

    }

    /**

     * Returns true if the given character can be converted to the

     * target character encoding.

     */

    public boolean canConvert(char c) {

        return encodeChar(c) != UNMAPPABLE_ENCODING;

    }

}