From d602ae483ee4ec9115c392a09b841e63d84518a7 Mon Sep 17 00:00:00 2001
From: Urs Fleisch <ufleisch@users.sourceforge.net>
Date: Wed, 30 Dec 2020 10:37:11 +0100
Subject: [PATCH] Read ID3v2.3 genres with multiple references to ID3v1 genres
 (#988)

As described in id3v2.3.0.txt (4.2.1, TCON), now multiple genres
are possible, e.g. "(51)(39)". Additionally, support the keywords
RX and CR.
---
 taglib/mpeg/id3v2/id3v2framefactory.cpp | 22 +++++++++++----------
 tests/test_id3v2.cpp                    | 26 ++++++++++++++++++++++++-
 2 files changed, 37 insertions(+), 11 deletions(-)

diff --git a/taglib/mpeg/id3v2/id3v2framefactory.cpp b/taglib/mpeg/id3v2/id3v2framefactory.cpp
index ad598332..e1e31307 100644
--- a/taglib/mpeg/id3v2/id3v2framefactory.cpp
+++ b/taglib/mpeg/id3v2/id3v2framefactory.cpp
@@ -60,22 +60,24 @@ namespace
 
     for(StringList::ConstIterator it = fields.begin(); it != fields.end(); ++it) {
       String s = *it;
-      int end = s.find(")");
+      int offset = 0;
+      int end = 0;
 
-      if(s.startsWith("(") && end > 0) {
+      while(s.length() > offset && s[offset] == '(' &&
+            (end = s.find(")", offset + 1)) > offset) {
         // "(12)Genre"
-        String text = s.substr(end + 1);
+        const String genreCode = s.substr(offset + 1, end - 1);
+        s = s.substr(end + 1);
         bool ok;
-        int number = s.substr(1, end - 1).toInt(&ok);
-        if(ok && number >= 0 && number <= 255 && !(ID3v1::genre(number) == text))
-          newfields.append(s.substr(1, end - 1));
-        if(!text.isEmpty())
-          newfields.append(text);
+        int number = genreCode.toInt(&ok);
+        if((ok && number >= 0 && number <= 255 &&
+            !(ID3v1::genre(number) == s)) ||
+           genreCode == "RX" || genreCode == "CR")
+          newfields.append(genreCode);
       }
-      else {
+      if(!s.isEmpty())
         // "Genre" or "12"
         newfields.append(s);
-      }
     }
 
     if(newfields.isEmpty())
diff --git a/tests/test_id3v2.cpp b/tests/test_id3v2.cpp
index dd260c0f..d202191e 100644
--- a/tests/test_id3v2.cpp
+++ b/tests/test_id3v2.cpp
@@ -101,6 +101,7 @@ class TestID3v2 : public CppUnit::TestFixture
   CPPUNIT_TEST(testSaveUTF16Comment);
   CPPUNIT_TEST(testUpdateGenre23_1);
   CPPUNIT_TEST(testUpdateGenre23_2);
+  CPPUNIT_TEST(testUpdateGenre23_3);
   CPPUNIT_TEST(testUpdateGenre24);
   CPPUNIT_TEST(testUpdateDate22);
   CPPUNIT_TEST(testDowngradeTo23);
@@ -686,7 +687,7 @@ public:
     // "Refinement" is different from the ID3v1 genre
     ID3v2::FrameFactory *factory = ID3v2::FrameFactory::instance();
     ByteVector data = ByteVector("TCON"                 // Frame ID
-                                 "\x00\x00\x00\x13"     // Frame size
+                                 "\x00\x00\x00\x0d"     // Frame size
                                  "\x00\x00"             // Frame flags
                                  "\x00"                 // Encoding
                                  "(4)Eurodisco", 23);   // Text
@@ -703,6 +704,29 @@ public:
     CPPUNIT_ASSERT_EQUAL(String("Disco Eurodisco"), tag.genre());
   }
 
+  void testUpdateGenre23_3()
+  {
+    // Multiple references and a refinement
+    ID3v2::FrameFactory *factory = ID3v2::FrameFactory::instance();
+    ByteVector data = ByteVector("TCON"                 // Frame ID
+                                 "\x00\x00\x00\x15"     // Frame size
+                                 "\x00\x00"             // Frame flags
+                                 "\x00"                 // Encoding
+                                 "(9)(138)Viking Metal", 31);   // Text
+    ID3v2::Header header;
+    header.setMajorVersion(3);
+    ID3v2::TextIdentificationFrame *frame =
+      dynamic_cast<TagLib::ID3v2::TextIdentificationFrame*>(factory->createFrame(data, &header));
+    CPPUNIT_ASSERT_EQUAL(3U, frame->fieldList().size());
+    CPPUNIT_ASSERT_EQUAL(String("9"), frame->fieldList()[0]);
+    CPPUNIT_ASSERT_EQUAL(String("138"), frame->fieldList()[1]);
+    CPPUNIT_ASSERT_EQUAL(String("Viking Metal"), frame->fieldList()[2]);
+
+    ID3v2::Tag tag;
+    tag.addFrame(frame);
+    CPPUNIT_ASSERT_EQUAL(String("Metal Black Metal Viking Metal"), tag.genre());
+  }
+
   void testUpdateGenre24()
   {
     ID3v2::FrameFactory *factory = ID3v2::FrameFactory::instance();