Media: Provide an unsetMetadata method

include/medialibrary/IMedia.h

@@ -156,6 +156,7 @@ class IMedia
         ///
         virtual bool setMetadata( MetadataType type, const std::string& value ) = 0;
         virtual bool setMetadata( MetadataType type, int64_t value ) = 0;
+        virtual bool unsetMetadata( MetadataType type ) = 0;
 };
 
 }

src/Media.cpp

@@ -322,6 +322,14 @@ bool Media::setMetadata( IMedia::MetadataType type, int64_t value )
     return m_metadata.set( static_cast<MDType>( type ), value );
 }
 
+bool Media::unsetMetadata(IMedia::MetadataType type)
+{
+    using MDType = typename std::underlying_type<IMedia::MetadataType>::type;
+    if ( m_metadata.isReady() == false )
+        m_metadata.init( m_id, IMedia::NbMeta );
+    return m_metadata.unset( static_cast<MDType>( type ) );
+}
+
 void Media::setReleaseDate( unsigned int date )
 {
     if ( m_releaseDate == date )

src/Media.h

@@ -113,6 +113,7 @@ class Media : public IMedia, public DatabaseHelpers<Media, policy::MediaTable>
         virtual const IMetadata& metadata( MetadataType type ) const override;
         virtual bool setMetadata( MetadataType type, const std::string& value ) override;
         virtual bool setMetadata( MetadataType type, int64_t value ) override;
+        virtual bool unsetMetadata( MetadataType type ) override;
 
         void setReleaseDate( unsigned int date );
         bool save();

test/unittest/MediaTests.cpp

@@ -542,6 +542,31 @@ TEST_F( Medias, MetadataOverride )
     ASSERT_EQ( "otter", md.str() );
 }
 
+TEST_F( Medias, MetadataUnset )
+{
+    auto m = ml->addMedia( "media.mp3" );
+    auto res = m->unsetMetadata( Media::MetadataType::ApplicationSpecific );
+    ASSERT_TRUE( res );
+
+    res = m->setMetadata( Media::MetadataType::ApplicationSpecific, "otters" );
+    ASSERT_TRUE( res );
+
+    auto& md = m->metadata( Media::MetadataType::ApplicationSpecific );
+    ASSERT_TRUE( md.isSet() );
+    ASSERT_EQ( "otters", md.str() );
+
+    res = m->unsetMetadata( Media::MetadataType::ApplicationSpecific );
+    ASSERT_TRUE( res );
+
+    ASSERT_FALSE( md.isSet() );
+
+    Reload();
+
+    m = ml->media( m->id() );
+    auto& md2 = m->metadata( Media::MetadataType::ApplicationSpecific );
+    ASSERT_FALSE( md2.isSet() );
+}
+
 TEST_F( Medias, ExternalMrl )
 {
     auto m = ml->addMedia( "https://foo.bar/sea-otters.mkv" );