/*

 * 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.

 *

 */

/*-

 *      Reads xbitmap format images into a DIBitmap structure.

 */

package sun.awt.image;

import java.io.*;

import java.awt.image.*;

/**

 * Parse files of the form:

 *

 * #define foo_width w

 * #define foo_height h

 * static char foo_bits[] = {

 * 0xnn,0xnn,0xnn,0xnn,0xnn,0xnn,0xnn,0xnn,0xnn,0xnn,0xnn,0xnn,0xnn,0xnn,0xnn,

 * 0xnn,0xnn,0xnn,0xnn,0xnn,0xnn,0xnn,0xnn,0xnn,0xnn,0xnn,0xnn,0xnn,0xnn,0xnn,

 * 0xnn,0xnn,0xnn,0xnn};

 *

 * @author James Gosling

 */

public class XbmImageDecoder extends ImageDecoder {

    private static byte XbmColormap[] = {(byte) 255, (byte) 255, (byte) 255,

                                         0, 0, 0};

    private static int XbmHints = (ImageConsumer.TOPDOWNLEFTRIGHT |

                                   ImageConsumer.COMPLETESCANLINES |

                                   ImageConsumer.SINGLEPASS |

                                   ImageConsumer.SINGLEFRAME);

    public XbmImageDecoder(InputStreamImageSource src, InputStream is) {

        super(src, is);

        if (!(input instanceof BufferedInputStream)) {

            // If the topmost stream is a metered stream,

            // we take forever to decode the image...

            input = new BufferedInputStream(input, 80);

        }

    }

    /**

     * An error has occurred. Throw an exception.

     */

    private static void error(String s1) throws ImageFormatException {

        throw new ImageFormatException(s1);

    }

    /**

     * produce an image from the stream.

     */

    public void produceImage() throws IOException, ImageFormatException {

        char nm[] = new char[80];

        int c;

        int i = 0;

        int state = 0;

        int H = 0;

        int W = 0;

        int x = 0;

        int y = 0;

        boolean start = true;

        byte raster[] = null;

        IndexColorModel model = null;

        while (!aborted && (c = input.read()) != -1) {

            if ('a' <= c && c <= 'z' ||

                    'A' <= c && c <= 'Z' ||

                    '0' <= c && c <= '9' || c == '#' || c == '_') {

                if (i < 78)

                    nm[i++] = (char) c;

            } else if (i > 0) {

                int nc = i;

                i = 0;

                if (start) {

                    if (nc != 7 ||

                        nm[0] != '#' ||

                        nm[1] != 'd' ||

                        nm[2] != 'e' ||

                        nm[3] != 'f' ||

                        nm[4] != 'i' ||

                        nm[5] != 'n' ||

                        nm[6] != 'e')

                    {

                        error("Not an XBM file");

                    }

                    start = false;

                }

                if (nm[nc - 1] == 'h')

                    state = 1;  /* expecting width */

                else if (nm[nc - 1] == 't' && nc > 1 && nm[nc - 2] == 'h')

                    state = 2;  /* expecting height */

                else if (nc > 2 && state < 0 && nm[0] == '0' && nm[1] == 'x') {

                    int n = 0;

                    for (int p = 2; p < nc; p++) {

                        c = nm[p];

                        if ('0' <= c && c <= '9')

                            c = c - '0';

                        else if ('A' <= c && c <= 'Z')

                            c = c - 'A' + 10;

                        else if ('a' <= c && c <= 'z')

                            c = c - 'a' + 10;

                        else

                            c = 0;

                        n = n * 16 + c;

                    }

                    for (int mask = 1; mask <= 0x80; mask <<= 1) {

                        if (x < W) {

                            if ((n & mask) != 0)

                                raster[x] = 1;

                            else

                                raster[x] = 0;

                        }

                        x++;

                    }

                    if (x >= W) {

                        if (setPixels(0, y, W, 1, model, raster, 0, W) <= 0) {

                            return;

                        }

                        x = 0;

                        if (y++ >= H) {

                            break;

                        }

                    }

                } else {

                    int n = 0;

                    for (int p = 0; p < nc; p++)

                        if ('0' <= (c = nm[p]) && c <= '9')

                            n = n * 10 + c - '0';

                        else {

                            n = -1;

                            break;

                        }

                    if (n > 0 && state > 0) {

                        if (state == 1)

                            W = n;

                        else

                            H = n;

                        if (W == 0 || H == 0)

                            state = 0;

                        else {

                            model = new IndexColorModel(8, 2, XbmColormap,

                                                        0, false, 0);

                            setDimensions(W, H);

                            setColorModel(model);

                            setHints(XbmHints);

                            headerComplete();

                            raster = new byte[W];

                            state = -1;

                        }

                    }

                }

            }

        }

        input.close();

        imageComplete(ImageConsumer.STATICIMAGEDONE, true);

    }

}