xref: /MusicPlayer2/MusicPlayer2/taglib/infotag.h (revision 2661106a96494c0a7dfab38bf1ae7b9565882443)
1 /***************************************************************************
2     copyright            : (C) 2012 by Tsuda Kageyu
3     email                : [email protected]
4  ***************************************************************************/
5 
6 /***************************************************************************
7  *   This library is free software; you can redistribute it and/or modify  *
8  *   it under the terms of the GNU Lesser General Public License version   *
9  *   2.1 as published by the Free Software Foundation.                     *
10  *                                                                         *
11  *   This library is distributed in the hope that it will be useful, but   *
12  *   WITHOUT ANY WARRANTY; without even the implied warranty of            *
13  *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU     *
14  *   Lesser General Public License for more details.                       *
15  *                                                                         *
16  *   You should have received a copy of the GNU Lesser General Public      *
17  *   License along with this library; if not, write to the Free Software   *
18  *   Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA         *
19  *   02110-1301  USA                                                       *
20  *                                                                         *
21  *   Alternatively, this file is available under the Mozilla Public        *
22  *   License Version 1.1.  You may obtain a copy of the License at         *
23  *   http://www.mozilla.org/MPL/                                           *
24  ***************************************************************************/
25 
26 #ifndef TAGLIB_INFOTAG_H
27 #define TAGLIB_INFOTAG_H
28 
29 #include "tag.h"
30 #include "tmap.h"
31 #include "tstring.h"
32 #include "tstringlist.h"
33 #include "tbytevector.h"
34 #include "taglib_export.h"
35 
36 namespace TagLib {
37 
38   class File;
39 
40   //! A RIFF INFO tag implementation.
41   namespace RIFF {
42   namespace Info {
43 
44     typedef Map<ByteVector, String> FieldListMap;
45 
46     //! A abstraction for the string to data encoding in Info tags.
47 
48     /*!
49      * RIFF INFO tag has no clear definitions about character encodings.
50      * In practice, local encoding of each system is largely used and UTF-8 is
51      * popular too.
52      *
53      * Here is an option to read and write tags in your preferred encoding
54      * by subclassing this class, reimplementing parse() and render() and setting
55      * your reimplementation as the default with Info::Tag::setStringHandler().
56      *
57      * \see ID3v1::Tag::setStringHandler()
58      */
59 
60     class TAGLIB_EXPORT StringHandler
61     {
62     public:
63       StringHandler();
64       ~StringHandler();
65 
66       /*!
67        * Decode a string from \a data.  The default implementation assumes that
68        * \a data is an UTF-8 character array.
69        */
70       virtual String parse(const ByteVector &data) const;
71 
72       /*!
73        * Encode a ByteVector with the data from \a s.  The default implementation
74        * assumes that \a s is an UTF-8 string.
75        */
76       virtual ByteVector render(const String &s) const;
77     };
78 
79     //! The main class in the ID3v2 implementation
80 
81     /*!
82      * This is the main class in the INFO tag implementation.  RIFF INFO tag is a
83      * metadata format found in WAV audio and AVI video files.  Though it is a part
84      * of Microsoft/IBM's RIFF specification, the author could not find the official
85      * documents about it.  So, this implementation is referring to unofficial documents
86      * online and some applications' behaviors especially Windows Explorer.
87      */
88     class TAGLIB_EXPORT Tag : public TagLib::Tag
89     {
90     public:
91       /*!
92        * Constructs an empty INFO tag.
93        */
94       Tag();
95 
96       /*!
97        * Constructs an INFO tag read from \a data which is contents of "LIST" chunk.
98        */
99       Tag(const ByteVector &data);
100 
101       virtual ~Tag();
102 
103       // Reimplementations
104 
105       virtual String title() const;
106       virtual String artist() const;
107       virtual String album() const;
108       virtual String comment() const;
109       virtual String genre() const;
110       virtual unsigned int year() const;
111       virtual unsigned int track() const;
112 
113       virtual void setTitle(const String &s);
114       virtual void setArtist(const String &s);
115       virtual void setAlbum(const String &s);
116       virtual void setComment(const String &s);
117       virtual void setGenre(const String &s);
118       virtual void setYear(unsigned int i);
119       virtual void setTrack(unsigned int i);
120 
121       virtual bool isEmpty() const;
122 
123       /*!
124        * Returns a copy of the internal fields of the tag.  The returned map directly
125        * reflects the contents of the "INFO" chunk.
126        *
127        * \note Modifying this map does not affect the tag's internal data.
128        * Use setFieldText() and removeField() instead.
129        *
130        * \see setFieldText()
131        * \see removeField()
132        */
133       FieldListMap fieldListMap() const;
134 
135       /*
136        * Gets the value of the field with the ID \a id.
137        */
138       String fieldText(const ByteVector &id) const;
139 
140       /*
141         * Sets the value of the field with the ID \a id to \a s.
142         * If the field does not exist, it is created.
143         * If \s is empty, the field is removed.
144         *
145         * \note fieldId must be four-byte long pure ASCII string.  This function
146         * performs nothing if fieldId is invalid.
147         */
148       void setFieldText(const ByteVector &id, const String &s);
149 
150       /*
151        * Removes the field with the ID \a id.
152        */
153       void removeField(const ByteVector &id);
154 
155       /*!
156        * Render the tag back to binary data, suitable to be written to disk.
157        *
158        * \note Returns empty ByteVector is the tag contains no fields.
159        */
160       ByteVector render() const;
161 
162       /*!
163        * Sets the string handler that decides how the text data will be
164        * converted to and from binary data.
165        * If the parameter \a handler is null, the previous handler is
166        * released and default UTF-8 handler is restored.
167        *
168        * \note The caller is responsible for deleting the previous handler
169        * as needed after it is released.
170        *
171        * \see StringHandler
172        */
173       static void setStringHandler(const StringHandler *handler);
174 
175     protected:
176       /*!
177        * Pareses the body of the tag in \a data.
178        */
179       void parse(const ByteVector &data);
180 
181 
182     private:
183       Tag(const Tag &);
184       Tag &operator=(const Tag &);
185 
186       class TagPrivate;
187       TagPrivate *d;
188     };
189   }}
190 }
191 
192 #endif
193