Subversion Repositories mkgmap

/*
 * Copyright (C) 2006 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: 10-Jan-2007
 */
package uk.me.parabola.imgfmt.app;

import java.util.regex.Pattern;

import uk.me.parabola.imgfmt.app.labelenc.CharacterEncoder;
import uk.me.parabola.imgfmt.app.labelenc.EncodedText;

/**
 * Labels are used for names of roads, points of interest etc.
 *
 * There are different storage formats.
 *
 * 1. A 6 bit compact uppercase ascii format, that has escape codes for some
 * special characters.
 *
 * 2. An 8 bit format.  This seems to be a fairly straightforward latin-1 like
 * encoding with no tricks to reduce the amount of space required.
 *
 * @author Steve Ratcliffe
 */
public class Label implements Comparable<Label> {

        private final String text;

        // The offset in to the data section.
        private int offset;

        public Label(String text) {
                this.text = text;
        }

        public int getLength() {
                if (text == null)
                        return 0;
                else
                        return text.length();
        }

        public String getText() {
                return text;
        }

        // highway shields and "thin" separators
        public final static Pattern SHIELDS = Pattern.compile("[\u0001-\u0006\u001b-\u001c]");

        // "fat" separators
        private final static Pattern SEPARATORS = Pattern.compile("[\u001d-\u001f]");

        // two or more whitespace characters
        private final static Pattern SQUASH_SPACES = Pattern.compile("\\s\\s+");

        public static String stripGarminCodes(String s) {
                if(s == null)
                        return null;
                s = SHIELDS.matcher(s).replaceAll(""); // remove
                s = SEPARATORS.matcher(s).replaceAll(" "); // replace with a space
                s = SQUASH_SPACES.matcher(s).replaceAll(" "); // replace with a space
                // a leading separator would have turned into a space so trim it
                return s.trim();
        }

        public static String squashSpaces(String s) {
                if(s == null || s.isEmpty())
                        return null;
                return SQUASH_SPACES.matcher(s).replaceAll(" "); // replace with single space
        }

        /**
         * The offset of this label in the LBL file.  The first byte of this file
         * is zero and an offset of zero means that the label has a zero length/is
         * empty.
         *
         * @return The offset within the LBL file of this string.
         */
        public int getOffset() {
                if (text == null || text.isEmpty())
                        return 0;
                else
                        return offset;
        }

        public void setOffset(int offset) {
                this.offset = offset;
        }

        /**
         * Write this label to the given img file.
         *
         * @param writer The LBL file to write to.
         * @param textEncoder The encoder to use for this text.  Converts the
         * unicode string representation to the correct byte stream for the file.
         * This depends on encoding format, character set etc.
         */
        public void write(ImgFileWriter writer, CharacterEncoder textEncoder) {
                EncodedText encText = textEncoder.encodeText(text);
                assert encText != null;

                if (encText.getLength() > 0)
                        writer.put(encText.getCtext(), 0, encText.getLength());
        }

        /**
         * String version of the label, for diagnostic purposes.
         */
        public String toString() {
                return "[" + offset + "]" + text;
        }

        public boolean equals(Object o) {
                if (this == o)
                        return true;
                if (o == null || !(o instanceof Label))
                        return false;

                return offset == ((Label) o).offset;

        }

        public int hashCode() {
                return offset;
        }

        /**
         * Note: this class has a natural ordering that is inconsistent with equals.
         * (But perhaps it shouldn't?)
         */
        public int compareTo(Label other) {
                if(this == other)
                        return 0;
                return text.compareToIgnoreCase(other.text);
        }
}