poi/src/scratchpad/src/org/apache/poi/hwmf/record/WmfPalette.java

package org.apache.poi.hwmf.record;

import java.io.IOException;

import org.apache.poi.util.LittleEndianConsts;
import org.apache.poi.util.LittleEndianInputStream;

public class WmfPalette {
    
    public static class PaletteEntry {
        // Values (1 byte):  An 8-bit unsigned integer that defines how the palette entry is to be used. 
        // The Values field MUST be 0x00 or one of the values in the PaletteEntryFlag Enumeration table.
        // Blue (1 byte): An 8-bit unsigned integer that defines the blue intensity value for the palette entry.
        // Green (1 byte): An 8-bit unsigned integer that defines the green intensity value for the palette entry.
        // Red (1 byte): An 8-bit unsigned integer that defines the red intensity value for the palette entry.
        int values, blue, green, red;
        
        public int init(LittleEndianInputStream leis) throws IOException {
            values = leis.readUByte();
            blue = leis.readUByte();
            green = leis.readUByte();
            red = leis.readUByte();
            return 4*LittleEndianConsts.BYTE_SIZE;
        }
    }
    
    public static abstract class WmfPaletteParent implements WmfRecord  {
    
        /**
         * Start (2 bytes):  A 16-bit unsigned integer that defines the offset into the Palette Object when
         * used with the META_SETPALENTRIES and META_ANIMATEPALETTE record types.
         * When used with META_CREATEPALETTE, it MUST be 0x0300
         */
        int start;
        
        /**
         * NumberOfEntries (2 bytes):  A 16-bit unsigned integer that defines the number of objects in
         * aPaletteEntries.  
         */
        int numberOfEntries;
        
        PaletteEntry entries[];
        
        public int init(LittleEndianInputStream leis, long recordSize, int recordFunction) throws IOException {
            start = leis.readUShort();
            numberOfEntries = leis.readUShort();
            int size = 2*LittleEndianConsts.SHORT_SIZE;
            entries = new PaletteEntry[numberOfEntries];
            for (int i=0; i<numberOfEntries; i++) {
                entries[i] = new PaletteEntry();
                size += entries[i].init(leis);
            }
            return size;
        }
    }
    
    /**
     * The META_CREATEPALETTE record creates a Palette Object
     */
    public static class WmfCreatePalette extends WmfPaletteParent {
        public WmfRecordType getRecordType() {
            return WmfRecordType.createPalette;
        }
    }

    /**
     * The META_SETPALENTRIES record defines RGB color values in a range of entries in the logical
     * palette that is defined in the playback device context.
     */
    public static class WmfSetPaletteEntries extends WmfPaletteParent {
        public WmfRecordType getRecordType() {
            return WmfRecordType.setPalEntries;
        }
    }
    
    /**
     * The META_RESIZEPALETTE record redefines the size of the logical palette that is defined in the
     * playback device context.
     */
    public static class WmfResizePalette implements WmfRecord {
        /**
         * A 16-bit unsigned integer that defines the number of entries in 
         * the logical palette.
         */
        int numberOfEntries;
        
        public WmfRecordType getRecordType() {
            return WmfRecordType.resizePalette;
        }
        
        public int init(LittleEndianInputStream leis, long recordSize, int recordFunction) throws IOException {
            numberOfEntries = leis.readUShort();
            return LittleEndianConsts.SHORT_SIZE;
        }        
    }

    /**
     * The META_SELECTPALETTE record defines the current logical palette with a specified Palette Object.
     */
    public static class WmfSelectPalette implements WmfRecord {
        /**
         * A 16-bit unsigned integer used to index into the WMF Object Table to get
         * the Palette Object to be selected.
         */
        int palette;

        public WmfRecordType getRecordType() {
            return WmfRecordType.selectPalette;
        }
        
        public int init(LittleEndianInputStream leis, long recordSize, int recordFunction) throws IOException {
            palette = leis.readUShort();
            return LittleEndianConsts.SHORT_SIZE;
        }        
    }

    /**
     * The META_REALIZEPALETTE record maps entries from the logical palette that
     * is defined in the playback device context to the system palette.
     */
    public static class WmfRealizePalette implements WmfRecord {
        public WmfRecordType getRecordType() { return WmfRecordType.realizePalette; }

        public int init(LittleEndianInputStream leis, long recordSize, int recordFunction) throws IOException {
            return 0;
        }
    }

    /**
     * The META_ANIMATEPALETTE record redefines entries in the logical palette that
     * is defined in the playback device context with the specified Palette object
     * 
     * The logical palette that is specified by the Palette object in this record is the
     * source of the palette changes, and the logical palette that is currently selected
     * into the playback device context is the destination. Entries in the destination
     * palette with the PC_RESERVED PaletteEntryFlag set SHOULD be modified by this record,
     * and entries with that flag clear SHOULD NOT be modified.
     * If none of the entries in the destination palette have the PC_RESERVED flag set, then
     * this record SHOULD have no effect.
     */
    public static class WmfAnimatePalette extends WmfPaletteParent {
        public WmfRecordType getRecordType() {
            return WmfRecordType.animatePalette;
        }
    }
}