1/*
2 * libid3tag - ID3 tag manipulation library
3 * Copyright (C) 2000-2003 Underbit Technologies, Inc.
4 *
5 * This program is free software; you can redistribute it and/or modify
6 * it under the terms of the GNU General Public License as published by
7 * the Free Software Foundation; either version 2 of the License, or
8 * (at your option) any later version.
9 *
10 * This program is distributed in the hope that it will be useful,
11 * but WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
13 * GNU General Public License for more details.
14 *
15 * You should have received a copy of the GNU General Public License
16 * along with this program; if not, write to the Free Software
17 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
18 *
19 * $Id: genre.c,v 1.7 2003/04/19 00:14:33 rob Exp $
20 */
21
22# ifdef HAVE_CONFIG_H
23#  include "config.h"
24# endif
25
26# include "global.h"
27
28# include "id3tag.h"
29# include "ucs4.h"
30
31/* genres are stored in ucs4 format */
32# include "genre.dat"
33
34# define NGENRES  (sizeof(genre_table) / sizeof(genre_table[0]))
35
36/*
37 * NAME:	genre->index()
38 * DESCRIPTION:	return an ID3v1 genre string indexed by number
39 */
40id3_ucs4_t const *id3_genre_index(unsigned int index)
41{
42  return (index < NGENRES) ? genre_table[index] : 0;
43}
44
45/*
46 * NAME:	genre->name()
47 * DESCRIPTION:	translate an ID3v2 genre number/keyword to its full name
48 */
49id3_ucs4_t const *id3_genre_name(id3_ucs4_t const *string)
50{
51  id3_ucs4_t const *ptr;
52  static id3_ucs4_t const genre_remix[] = { 'R', 'e', 'm', 'i', 'x', 0 };
53  static id3_ucs4_t const genre_cover[] = { 'C', 'o', 'v', 'e', 'r', 0 };
54  unsigned long number;
55
56  if (string == 0 || *string == 0)
57    return id3_ucs4_empty;
58
59  if (string[0] == 'R' && string[1] == 'X' && string[2] == 0)
60    return genre_remix;
61  if (string[0] == 'C' && string[1] == 'R' && string[2] == 0)
62    return genre_cover;
63
64  for (ptr = string; *ptr; ++ptr) {
65    if (*ptr < '0' || *ptr > '9')
66      return string;
67  }
68
69  number = id3_ucs4_getnumber(string);
70
71  return (number < NGENRES) ? genre_table[number] : string;
72}
73
74/*
75 * NAME:	translate()
76 * DESCRIPTION:	return a canonicalized character for testing genre equivalence
77 */
78static
79id3_ucs4_t translate(id3_ucs4_t ch)
80{
81  if (ch) {
82    if (ch >= 'A' && ch <= 'Z')
83      ch += 'a' - 'A';
84
85    if (ch < 'a' || ch > 'z')
86      ch = ID3_UCS4_REPLACEMENTCHAR;
87  }
88
89  return ch;
90}
91
92/*
93 * NAME:	compare()
94 * DESCRIPTION:	test two ucs4 genre strings for equivalence
95 */
96static
97int compare(id3_ucs4_t const *str1, id3_ucs4_t const *str2)
98{
99  id3_ucs4_t c1, c2;
100
101  if (str1 == str2)
102    return 1;
103
104  do {
105    do
106      c1 = translate(*str1++);
107    while (c1 == ID3_UCS4_REPLACEMENTCHAR);
108
109    do
110      c2 = translate(*str2++);
111    while (c2 == ID3_UCS4_REPLACEMENTCHAR);
112  }
113  while (c1 && c1 == c2);
114
115  return c1 == c2;
116}
117
118/*
119 * NAME:	genre->number()
120 * DESCRIPTION:	translate an ID3v2 genre name/number to its ID3v1 index number
121 */
122int id3_genre_number(id3_ucs4_t const *string)
123{
124  id3_ucs4_t const *ptr;
125  int i;
126
127  if (string == 0 || *string == 0)
128    return -1;
129
130  for (ptr = string; *ptr; ++ptr) {
131    if (*ptr < '0' || *ptr > '9')
132      break;
133  }
134
135  if (*ptr == 0) {
136    unsigned long number;
137
138    number = id3_ucs4_getnumber(string);
139
140    return (number <= 0xff) ? number : -1;
141  }
142
143  for (i = 0; i < NGENRES; ++i) {
144    if (compare(string, genre_table[i]))
145      return i;
146  }
147
148  /* no equivalent */
149
150  return -1;
151}
152