Improve support for arbitrary attachments.

// FREEBIE

src/Messages/Attachments/OWSAttachmentsProcessor.m

@@ -79,20 +79,9 @@ NS_ASSUME_NONNULL_BEGIN
 
         [attachmentIds addObject:pointer.uniqueId];
 
-        // TODO: We need to revisit isSupportedMIMEType.
-        if ([MIMETypeUtil isSupportedMIMEType:pointer.contentType] ||
-            [pointer.contentType isEqualToString:OWSMimeTypeOversizeTextMessage] ||
-            [pointer.contentType isEqualToString:OWSMimeTypeUnknownForTests]) {
         [pointer save];
         [supportedAttachmentPointers addObject:pointer];
         [supportedAttachmentIds addObject:pointer.uniqueId];
-        } else {
-            DDLogError(@"%@ Received unsupported attachment of type: %@", self.tag, pointer.contentType);
-            TSInfoMessage *infoMessage = [[TSInfoMessage alloc] initWithTimestamp:timestamp
-                                                                         inThread:thread
-                                                                      messageType:TSInfoMessageTypeUnsupportedMessage];
-            [infoMessage save];
-        }
     }
 
     _attachmentIds = [attachmentIds copy];

src/Util/MIMETypeUtil.h

@@ -9,7 +9,6 @@ extern NSString *const OWSMimeTypeUnknownForTests;
 
 @interface MIMETypeUtil : NSObject
 
-+ (BOOL)isSupportedMIMEType:(NSString *)contentType;
 + (BOOL)isSupportedVideoMIMEType:(NSString *)contentType;
 + (BOOL)isSupportedAudioMIMEType:(NSString *)contentType;
 + (BOOL)isSupportedImageMIMEType:(NSString *)contentType;

src/Util/MIMETypeUtil.m

@@ -200,11 +200,6 @@ NSString *const OWSMimeTypeUnknownForTests = @"unknown/mimetype";
     return [[self supportedBinaryDataMIMETypesToExtensionTypes] objectForKey:contentType] != nil;
 }
 
-+ (BOOL)isSupportedMIMEType:(NSString *)contentType {
-    return [self isSupportedImageMIMEType:contentType] || [self isSupportedAudioMIMEType:contentType] ||
-           [self isSupportedVideoMIMEType:contentType] || [self isSupportedAnimatedMIMEType:contentType];
-}
-
 + (BOOL)isSupportedVideoFile:(NSString *)filePath {
     return [[self supportedVideoExtensionTypesToMIMETypes] objectForKey:[filePath pathExtension]] != nil;
 }
@@ -294,9 +289,18 @@ NSString *const OWSMimeTypeUnknownForTests = @"unknown/mimetype";
     } else if ([self isBinaryData:contentType]) {
         return [MIMETypeUtil filePathForBinaryData:uniqueId ofMIMEType:contentType inFolder:folder];
     } else if ([contentType isEqualToString:OWSMimeTypeOversizeTextMessage]) {
-        return [MIMETypeUtil filePathForOversizeTextMessage:uniqueId inFolder:folder];
+        // This file extension is arbitrary - it should never be exposed to the user or
+        // be used outside the app.
+        return [self filePathForData:uniqueId withFileExtension:@"signal-text-message" inFolder:folder];
     } else if ([contentType isEqualToString:OWSMimeTypeUnknownForTests]) {
-        return [MIMETypeUtil filePathForUnknownContent:uniqueId inFolder:folder];
+        // This file extension is arbitrary - it should never be exposed to the user or
+        // be used outside the app.
+        return [self filePathForData:uniqueId withFileExtension:@"unknown" inFolder:folder];
+    }
+
+    NSString *fileExtension = [self fileExtensionForMIMEType:contentType];
+    if (fileExtension) {
+        return [self filePathForData:uniqueId withFileExtension:fileExtension inFolder:folder];
     }
 
     DDLogError(@"Got asked for path of file %@ which is unsupported", contentType);
@@ -350,18 +354,11 @@ NSString *const OWSMimeTypeUnknownForTests = @"unknown/mimetype";
         stringByAppendingPathExtension:[self getSupportedExtensionFromBinaryDataMIMEType:contentType]];
 }
 
-+ (NSString *)filePathForOversizeTextMessage:(NSString *)uniqueId inFolder:(NSString *)folder {
++ (NSString *)filePathForData:(NSString *)uniqueId
-    // This file extension is arbitrary - it should never be exposed to the user or
+            withFileExtension:(NSString *)fileExtension
-    // be used outside the app.
+                     inFolder:(NSString *)folder
-    return [[folder stringByAppendingFormat:@"/%@", uniqueId]
+{
-            stringByAppendingPathExtension:@"signal-text-message"];
+    return [[folder stringByAppendingFormat:@"/%@", uniqueId] stringByAppendingPathExtension:fileExtension];
-}
-
-+ (NSString *)filePathForUnknownContent:(NSString *)uniqueId inFolder:(NSString *)folder {
-    // This file extension is arbitrary - it should never be exposed to the user or
-    // be used outside the app.
-    return [[folder stringByAppendingFormat:@"/%@", uniqueId]
-            stringByAppendingPathExtension:@"unknown"];
 }
 
 #if TARGET_OS_IPHONE