Subversion Repositories mkgmap

/*
 * Copyright (C) 2007 Steve Ratcliffe
 *
 *  This program is free software; you can redistribute it and/or modify
 *  it under the terms of the GNU General Public License version 2 as
 *  published by the Free Software Foundation.
 *
 *  This program 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 for more details.
 *
 *
 * Author: Steve Ratcliffe
 * Create date: Dec 19, 2007
 */
package uk.me.parabola.imgfmt.mps;

import java.io.Closeable;
import java.io.IOException;
import java.util.ArrayList;
import java.util.List;

import uk.me.parabola.imgfmt.app.BufferedImgFileReader;
import uk.me.parabola.imgfmt.app.ImgFileReader;
import uk.me.parabola.imgfmt.app.labelenc.CharacterDecoder;
import uk.me.parabola.imgfmt.app.labelenc.CodeFunctions;
import uk.me.parabola.imgfmt.fs.ImgChannel;

/**
 * This file is a description of the map set that is loaded into the
 * gmapsupp.img file and an index of the maps that it contains.
 *
 * It is different than all the other files that fit inside the gmapsupp file
 * in that it doesn't contain the common header.  So it does not extend ImgFile.
 *
 * @author Steve Ratcliffe
 */
public class MpsFileReader implements Closeable {

        private final List<MapBlock> maps = new ArrayList<>();
        private final List<ProductBlock> products = new ArrayList<>();

        private final ImgChannel chan;
        private final ImgFileReader reader;
        private final CharacterDecoder decoder;
        private final int codePage;

        public MpsFileReader(ImgChannel chan, int codePage) {
                this.chan = chan;
                this.reader = new BufferedImgFileReader(chan);

                this.codePage = codePage;
                CodeFunctions funcs = CodeFunctions.createEncoderForLBL(0, codePage);
                decoder = funcs.getDecoder();

                readBlocks();
        }

        private void readBlocks() {
                byte type;
                while ((type = reader.get()) > 0) {
                        int len = reader.get2u();

                        switch (type) {
                        case 0x4c:
                                readMapBlock();
                                break;
                        case 0x46:
                                readProductBlock();
                                break;
                        default:
                                // We always know the length, so just read over it
                                reader.get(len);
                                break;
                        }
                }
        }

        private void readMapBlock() {
                MapBlock block = new MapBlock(codePage);
                int val = reader.get4();
                block.setIds(val >>> 16, val & 0xffff);
                block.setMapNumber(reader.get4());

                byte[] zString = reader.getZString();
                block.setSeriesName(decodeToString(zString));
                block.setMapDescription(decodeToString(reader.getZString()));
                block.setAreaName(decodeToString(reader.getZString()));
                block.setHexNumber(reader.get4());
                reader.get4();
                maps.add(block);
        }

        private void readProductBlock() {
                ProductBlock block = new ProductBlock(codePage);
                block.setProductId(reader.get2u());
                block.setFamilyId(reader.get2u());
                block.setDescription(decodeToString(reader.getZString()));
                products.add(block);
        }

        private String decodeToString(byte[] zString) {
                decoder.reset();
                for (byte b : zString)
                        decoder.addByte(b);

                return decoder.getText().getText();
        }

        public List<MapBlock> getMaps() {
                return maps;
        }

        public List<ProductBlock> getProducts() {
                return products;
        }

        public void close() throws IOException {
                chan.close();
        }
}