[Tag Reading] Moved external cover art reader

Moved external cover art reader to a place where it can be used for any
format, even formats unsupported by Metadata Reader interfaces.

Signed-off-by: Christopher Snowhill <kode54@gmail.com>

Audio/PluginController.mm

@@ -642,6 +642,19 @@ static NSString *xmlEscapeString(NSString * string) {
 	return [[decoder alloc] init];
 }
 
++ (BOOL)isCoverFile:(NSString *)fileName {
+	for(NSString *coverFileName in [PluginController coverNames]) {
+		if([[[[fileName lastPathComponent] stringByDeletingPathExtension] lowercaseString] hasSuffix:coverFileName]) {
+			return true;
+		}
+	}
+	return false;
+}
+
++ (NSArray *)coverNames {
+	return @[@"cover", @"folder", @"album", @"front"];
+}
+
 - (NSDictionary *)metadataForURL:(NSURL *)url skipCue:(BOOL)skip {
 	NSString *urlScheme = [url scheme];
 	if([urlScheme isEqualToString:@"http"] ||
@@ -651,6 +664,7 @@ static NSString *xmlEscapeString(NSString * string) {
 	NSDictionary *cacheData = cache_access_metadata(url);
 	if(cacheData) return cacheData;
 
+	do {
 		NSString *ext = [url pathExtension];
 		NSArray *readers = [metadataReaders objectForKey:[ext lowercaseString]];
 		NSString *classString;
@@ -665,26 +679,61 @@ static NSString *xmlEscapeString(NSString * string) {
 							++i;
 					}
 					cacheData = [CogMetadataReaderMulti metadataForURL:url readers:_readers];
-				cache_insert_metadata(url, cacheData);
+					break;
-				return cacheData;
 				}
 				cacheData = [CogMetadataReaderMulti metadataForURL:url readers:readers];
-			cache_insert_metadata(url, cacheData);
+				break;
-			return cacheData;
 			} else {
 				classString = [readers objectAtIndex:0];
 			}
 		} else {
-		return nil;
+			cacheData = nil;
+			break;
 		}
 
 		if(skip && [classString isEqualToString:@"CueSheetMetadataReader"]) {
-		return nil;
+			cacheData = nil;
+			break;
 		}
 
 		Class metadataReader = NSClassFromString(classString);
 
 		cacheData = [metadataReader metadataForURL:url];
+	} while(0);
+
+	if(cacheData == nil) {
+		cacheData = [NSDictionary dictionary];
+	}
+
+	if(cacheData) {
+		NSData *image = [cacheData objectForKey:@"albumArt"];
+
+		if(nil == image) {
+			// Try to load image from external file
+
+			NSString *path = [[url path] stringByDeletingLastPathComponent];
+
+			// Gather list of candidate image files
+
+			NSArray *fileNames = [[NSFileManager defaultManager] contentsOfDirectoryAtPath:path error:nil];
+			NSArray *types = @[@"jpg", @"jpeg", @"png", @"gif", @"webp", @"avif"];
+			NSArray *imageFileNames = [fileNames pathsMatchingExtensions:types];
+
+			for(NSString *fileName in imageFileNames) {
+				if([PluginController isCoverFile:fileName]) {
+					image = [NSData dataWithContentsOfFile:[path stringByAppendingPathComponent:fileName]];
+					break;
+				}
+			}
+
+			if(image) {
+				NSMutableDictionary *data = [cacheData mutableCopy];
+				[data setValue:image forKey:@"albumArt"];
+				cacheData = data;
+			}
+		}
+	}
+
 	cache_insert_metadata(url, cacheData);
 	return cacheData;
 }

Plugins/TagLib/TagLibMetadataReader.h

@@ -13,7 +13,4 @@
 @interface TagLibMetadataReader : NSObject <CogMetadataReader> {
 }
 
-+ (BOOL)isCoverFile:(NSString *)fileName;
-+ (NSArray *)coverNames;
-
 @end

Plugins/TagLib/TagLibMetadataReader.m

@@ -196,25 +196,6 @@
 			}
 		}
 
-		if(nil == image) {
-			// Try to load image from external file
-
-			NSString *path = [[url path] stringByDeletingLastPathComponent];
-
-			// Gather list of candidate image files
-
-			NSArray *fileNames = [[NSFileManager defaultManager] contentsOfDirectoryAtPath:path error:nil];
-			NSArray *types = @[@"jpg", @"jpeg", @"png", @"gif", @"webp", @"avif"];
-			NSArray *imageFileNames = [fileNames pathsMatchingExtensions:types];
-
-			for(NSString *fileName in imageFileNames) {
-				if([TagLibMetadataReader isCoverFile:fileName]) {
-					image = [NSData dataWithContentsOfFile:[path stringByAppendingPathComponent:fileName]];
-					break;
-				}
-			}
-		}
-
 		if(nil != image) {
 			[dict setObject:image forKey:@"albumArt"];
 		}
@@ -225,19 +206,6 @@
 	return dict;
 }
 
-+ (BOOL)isCoverFile:(NSString *)fileName {
-	for(NSString *coverFileName in [TagLibMetadataReader coverNames]) {
-		if([[[[fileName lastPathComponent] stringByDeletingPathExtension] lowercaseString] hasSuffix:coverFileName]) {
-			return true;
-		}
-	}
-	return false;
-}
-
-+ (NSArray *)coverNames {
-	return @[@"cover", @"folder", @"album", @"front"];
-}
-
 + (NSArray *)fileTypes {
 	// May be a way to get a list of supported formats
 	return @[@"ape", @"asf", @"wma", @"ogg", @"opus", @"mpc", @"flac", @"mp3", @"tak", @"ac3", @"apl", @"dts", @"dtshd", @"tta", @"wav", @"aif", @"aiff", @"wv", @"wvp"];