001/*
002 * Licensed to the Apache Software Foundation (ASF) under one or more
003 * contributor license agreements.  See the NOTICE file distributed with
004 * this work for additional information regarding copyright ownership.
005 * The ASF licenses this file to You under the Apache License, Version 2.0
006 * (the "License"); you may not use this file except in compliance with
007 * the License.  You may obtain a copy of the License at
008 *
009 *      http://www.apache.org/licenses/LICENSE-2.0
010 *
011 * Unless required by applicable law or agreed to in writing, software
012 * distributed under the License is distributed on an "AS IS" BASIS,
013 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
014 * See the License for the specific language governing permissions and
015 * limitations under the License.
016 */
017package org.apache.commons.imaging.formats.tiff.taginfos;
018
019import java.nio.ByteOrder;
020import java.nio.charset.StandardCharsets;
021
022import org.apache.commons.imaging.ImageWriteException;
023import org.apache.commons.imaging.formats.tiff.constants.TiffDirectoryType;
024import org.apache.commons.imaging.formats.tiff.fieldtypes.FieldType;
025
026public class TagInfoAscii extends TagInfo {
027    public TagInfoAscii(final String name, final int tag, final int length,
028            final TiffDirectoryType directoryType) {
029        super(name, tag, FieldType.ASCII, length, directoryType);
030    }
031
032    public String[] getValue(final ByteOrder byteOrder, final byte[] bytes) {
033        int nullCount = 0;
034        for (int i = 0; i < bytes.length - 1; i++) {
035            if (bytes[i] == 0) {
036                nullCount++;
037            }
038        }
039        final String[] strings = new String[nullCount + 1];
040        int stringsAdded = 0;
041        strings[0] = ""; // if we have a 0 length string
042        int nextStringPos = 0;
043        // According to the Exiftool FAQ, http://www.metadataworkinggroup.org
044        // specifies that the TIFF ASCII fields are actually UTF-8.
045        // Exiftool however allows you to configure the charset used.
046        for (int i = 0; i < bytes.length; i++) {
047            if (bytes[i] == 0) {
048                final String string = new String(bytes, nextStringPos, i
049                        - nextStringPos, StandardCharsets.UTF_8);
050                strings[stringsAdded++] = string;
051                nextStringPos = i + 1;
052            }
053        }
054        if (nextStringPos < bytes.length) {
055            // Buggy file, string wasn't null terminated
056            final String string = new String(bytes, nextStringPos, bytes.length
057                    - nextStringPos, StandardCharsets.UTF_8);
058            strings[stringsAdded++] = string;
059        }
060        return strings;
061    }
062
063    public byte[] encodeValue(final ByteOrder byteOrder, final String... values)
064            throws ImageWriteException {
065        return FieldType.ASCII.writeData(values, byteOrder);
066    }
067}