Adds support for image previews

Just need to append ?preview=1 to attachment fetch operation.

Dumped Classes/IMSharedUtilities_ClassDump.h

@@ -18,12 +18,18 @@ struct IMFileLocation_t {
     int _field5;
 };
 
-struct IMPreviewConstraints {
+typedef struct IMPreviewConstraints {
-    double _field1;
+    CGFloat maxPxWidth;
-    struct CGSize _field2;
+    CGSize minThumbnailPxSize;
-    double _field3;
+    CGFloat scale;
-    char _field4;
+    BOOL isSticker;
-};
+    BOOL generateMetadata;
+} IMPreviewConstraints;
+
+extern IMPreviewConstraints IMPreviewConstraintsFromDictionary(NSDictionary *dictionary);
+extern NSDictionary *IMPreviewConstraintsDictionaryFromConstraint(IMPreviewConstraints constraint);
+extern BOOL IMPreviewConstraintsEqualToConstraints(IMPreviewConstraints constraints1, IMPreviewConstraints constraints2);
+extern IMPreviewConstraints IMPreviewConstraintsZero(void);
 
 struct _TidyDoc {
     int _field1;
@@ -155,6 +161,8 @@ struct __va_list_tag {
 - (void)setObject:(id)arg1 forKey:(id)arg2;
 @end
 
+extern NSURL* IMAttachmentPreviewFileURL(NSURL *attachmentURL, NSString *extension, BOOL generateIntermediaryDirectories);
+
 @protocol IMPreviewGeneratorProtocol
 + (BOOL)shouldShadePreview;
 + (BOOL)shouldScaleUpPreview;

MessagesBridge.xcodeproj/project.pbxproj

@@ -73,6 +73,10 @@
 		CD14F1A4219FF22700E7DD22 /* IMMessageItem+Encoded.m in Sources */ = {isa = PBXBuildFile; fileRef = CD14F1A3219FF22700E7DD22 /* IMMessageItem+Encoded.m */; };
 		CD14F1AA219FF3B800E7DD22 /* MBIMUpdateQueue.m in Sources */ = {isa = PBXBuildFile; fileRef = CD14F1A9219FF3B800E7DD22 /* MBIMUpdateQueue.m */; };
 		CD14F1AD219FFAE100E7DD22 /* MBIMConcurrentHTTPServer.m in Sources */ = {isa = PBXBuildFile; fileRef = CD14F1AC219FFAE100E7DD22 /* MBIMConcurrentHTTPServer.m */; };
+		CD2782BC29527FE500C0C030 /* IMSharedUtilities.framework in Frameworks */ = {isa = PBXBuildFile; fileRef = CD2782BB29527FE500C0C030 /* IMSharedUtilities.framework */; };
+		CD2782BF2952832B00C0C030 /* MBIMImageUtils.m in Sources */ = {isa = PBXBuildFile; fileRef = CD2782BE2952832B00C0C030 /* MBIMImageUtils.m */; };
+		CD2782FE2952875F00C0C030 /* CoreGraphics.framework in Frameworks */ = {isa = PBXBuildFile; fileRef = CD2782FD2952875F00C0C030 /* CoreGraphics.framework */; };
+		CD2783002952876700C0C030 /* ImageIO.framework in Frameworks */ = {isa = PBXBuildFile; fileRef = CD2782FF2952876700C0C030 /* ImageIO.framework */; };
 		CD2ECEC2269539100055E302 /* MBIMAuthenticateOperation.m in Sources */ = {isa = PBXBuildFile; fileRef = CD2ECEC1269539100055E302 /* MBIMAuthenticateOperation.m */; };
 		CD2ECEC526953F2A0055E302 /* MBIMAuthToken.m in Sources */ = {isa = PBXBuildFile; fileRef = CD2ECEC426953F2A0055E302 /* MBIMAuthToken.m */; };
 		CD602056219B5DFD0024D9C5 /* MBIMBridgeOperation.m in Sources */ = {isa = PBXBuildFile; fileRef = CD602055219B5DFD0024D9C5 /* MBIMBridgeOperation.m */; };
@@ -223,6 +227,11 @@
 		CD14F1A9219FF3B800E7DD22 /* MBIMUpdateQueue.m */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.c.objc; path = MBIMUpdateQueue.m; sourceTree = "<group>"; };
 		CD14F1AB219FFAE100E7DD22 /* MBIMConcurrentHTTPServer.h */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.c.h; path = MBIMConcurrentHTTPServer.h; sourceTree = "<group>"; };
 		CD14F1AC219FFAE100E7DD22 /* MBIMConcurrentHTTPServer.m */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.c.objc; path = MBIMConcurrentHTTPServer.m; sourceTree = "<group>"; };
+		CD2782BB29527FE500C0C030 /* IMSharedUtilities.framework */ = {isa = PBXFileReference; lastKnownFileType = wrapper.framework; name = IMSharedUtilities.framework; path = Platforms/MacOSX.platform/Developer/SDKs/MacOSX14.0.Internal.sdk/System/Library/PrivateFrameworks/IMSharedUtilities.framework; sourceTree = DEVELOPER_DIR; };
+		CD2782BD2952832B00C0C030 /* MBIMImageUtils.h */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.c.h; path = MBIMImageUtils.h; sourceTree = "<group>"; };
+		CD2782BE2952832B00C0C030 /* MBIMImageUtils.m */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.c.objc; path = MBIMImageUtils.m; sourceTree = "<group>"; };
+		CD2782FD2952875F00C0C030 /* CoreGraphics.framework */ = {isa = PBXFileReference; lastKnownFileType = wrapper.framework; name = CoreGraphics.framework; path = System/Library/Frameworks/CoreGraphics.framework; sourceTree = SDKROOT; };
+		CD2782FF2952876700C0C030 /* ImageIO.framework */ = {isa = PBXFileReference; lastKnownFileType = wrapper.framework; name = ImageIO.framework; path = System/Library/Frameworks/ImageIO.framework; sourceTree = SDKROOT; };
 		CD2ECEC0269539100055E302 /* MBIMAuthenticateOperation.h */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.c.h; path = MBIMAuthenticateOperation.h; sourceTree = "<group>"; };
 		CD2ECEC1269539100055E302 /* MBIMAuthenticateOperation.m */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.c.objc; path = MBIMAuthenticateOperation.m; sourceTree = "<group>"; };
 		CD2ECEC326953F2A0055E302 /* MBIMAuthToken.h */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.c.h; path = MBIMAuthToken.h; sourceTree = "<group>"; };
@@ -287,8 +296,11 @@
 			isa = PBXFrameworksBuildPhase;
 			buildActionMask = 2147483647;
 			files = (
+				CD2782BC29527FE500C0C030 /* IMSharedUtilities.framework in Frameworks */,
 				1A257CCB23A8681200A4A2C8 /* Security.framework in Frameworks */,
+				CD2783002952876700C0C030 /* ImageIO.framework in Frameworks */,
 				1ACFCFDF219EB31400E2C237 /* CocoaHTTPServer.framework in Frameworks */,
+				CD2782FE2952875F00C0C030 /* CoreGraphics.framework in Frameworks */,
 				1A257CC923A867EF00A4A2C8 /* IMCore.framework in Frameworks */,
 			);
 			runOnlyForDeploymentPostprocessing = 0;
@@ -334,6 +346,9 @@
 		1A0C445E219A45B400F2AC00 /* Frameworks */ = {
 			isa = PBXGroup;
 			children = (
+				CD2782FF2952876700C0C030 /* ImageIO.framework */,
+				CD2782FD2952875F00C0C030 /* CoreGraphics.framework */,
+				CD2782BB29527FE500C0C030 /* IMSharedUtilities.framework */,
 				1A257CCA23A8681200A4A2C8 /* Security.framework */,
 				1A257CC823A867EF00A4A2C8 /* IMCore.framework */,
 			);
@@ -370,6 +385,8 @@
 				CD936A31289B353F0093A1AC /* MBIMErrorResponse.m */,
 				1AA43E93219EC38E00EDF1A7 /* MBIMHTTPUtilities.h */,
 				1AA43E94219EC38E00EDF1A7 /* MBIMHTTPUtilities.m */,
+				CD2782BD2952832B00C0C030 /* MBIMImageUtils.h */,
+				CD2782BE2952832B00C0C030 /* MBIMImageUtils.m */,
 			);
 			path = Utilities;
 			sourceTree = "<group>";
@@ -893,6 +910,7 @@
 				CD602056219B5DFD0024D9C5 /* MBIMBridgeOperation.m in Sources */,
 				CD60205F219B674B0024D9C5 /* MBIMConversationListOperation.m in Sources */,
 				CDE4556421A3578A0041F5DD /* IMChat+Encoded.m in Sources */,
+				CD2782BF2952832B00C0C030 /* MBIMImageUtils.m in Sources */,
 				1AA43E8F219EBB2D00EDF1A7 /* MBIMJSONDataResponse.m in Sources */,
 				CD936A32289B353F0093A1AC /* MBIMErrorResponse.m in Sources */,
 				CD2ECEC2269539100055E302 /* MBIMAuthenticateOperation.m in Sources */,

kordophone/Bridge/Operations/MBIMFetchAttachmentOperation.m

@@ -8,8 +8,11 @@
 
 #import "MBIMFetchAttachmentOperation.h"
 #import "MBIMDataResponse.h"
+#import "MBIMImageUtils.h"
 
 #import "IMCore_ClassDump.h"
+#import "IMSharedUtilities_ClassDump.h"
+#import <CoreGraphics/CoreGraphics.h>
 
 @implementation MBIMFetchAttachmentOperation
 
@@ -24,8 +27,8 @@
 {
     NSObject<HTTPResponse> *response = nil;
     do {
+        BOOL preview = [[self valueForQueryItemWithName:@"preview"] boolValue];
         NSString *guid = [self valueForQueryItemWithName:@"guid"];
-        
         if (!guid) {
             MBIMLogInfo(@"No query item provided");
             response = [[HTTPErrorResponse alloc] initWithErrorCode:500];
@@ -45,22 +48,65 @@
             break;
         }
         
-        NSString *localPath = [transfer localPath];
+        NSData *responseData = nil;
-        NSData *responseData = [NSData dataWithContentsOfFile:localPath];
+        NSURL *localURL = [transfer localURL];
+        NSString *extension = [[localURL pathExtension] lowercaseString];
+        if (preview) {
+            NSURL *previewURL = IMAttachmentPreviewFileURL(localURL, extension, YES);
+            if (![[NSFileManager defaultManager] fileExistsAtPath:[previewURL path]]) {
+                MBIMLogInfo(@"Generating preview image for guid: %@ at %@", guid, [previewURL path]);
+                
+                // Fetch preview constraints from transfer
+                NSDictionary *previewConstraintsDict = [[transfer attributionInfo] objectForKey:@"pgenszc"];
+                if (!previewConstraintsDict) {
+                    MBIMLogInfo(@"No preview constraints for attachment guid: %@", guid);
+                    response = [[HTTPErrorResponse alloc] initWithErrorCode:500];
+                    break;
+                }
+                
+                IMPreviewConstraints constraints = IMPreviewConstraintsFromDictionary(previewConstraintsDict);
+                
+                // Generate preview using preview generator manager
+                NSError *error = nil;
+                IMPreviewGeneratorManager *generator = [IMPreviewGeneratorManager sharedInstance];
+                CGImageRef previewImage = [generator newPreviewFromSourceURL:localURL withPreviewConstraints:constraints error:&error];
+                if (error) {
+                    MBIMLogInfo(@"Unable to generate preview for attachment guid: %@", guid);
+                    response = [[HTTPErrorResponse alloc] initWithErrorCode:500];
+                    break;
+                }
+                
+                responseData = MBIMCGImageJPEGRepresentation(previewImage);
+                
+                // Persist JPEG preview to disk
+                [responseData writeToURL:previewURL atomically:YES];
+            } else {
+                // File exists
+                MBIMLogInfo(@"Using cached preview image for guid: %@ at %@", guid, [previewURL path]);
+                responseData = [NSData dataWithContentsOfURL:previewURL];
+            }
+        } else {
+            responseData = [NSData dataWithContentsOfURL:localURL];
+        }
+         
         if (!responseData) {
-            MBIMLogInfo(@"Wasn't able to load data from local path: %@", localPath);
+            MBIMLogInfo(@"Wasn't able to load data for guid: %@", guid);
             response = [[HTTPErrorResponse alloc] initWithErrorCode:404];
             break;
         }
         
         NSString *mimeType = [transfer mimeType];
+        if ([mimeType isEqualToString:@"image/heic"]) {
+            // TODO: We should convert this to JPEG here. I don't want clients to have to deal with HEIC.
+            MBIMLogInfo(@"WARNING: Returning HEIC data for attachment %@", guid);
+        }
+        
         // It's unusual, but if this is nil, try to guess the MIME type based on the filename
         if (!mimeType) {
-            NSString *extension = [[localPath pathExtension] lowercaseString];
-
             // XXX: REALLY hacky
             mimeType = [NSString stringWithFormat:@"image/%@", extension];
         }
+        
         response = [[MBIMDataResponse alloc] initWithData:responseData contentType:mimeType];
     } while (0);
     

kordophone/Bridge/Operations/Utilities/MBIMImageUtils.h

@@ -0,0 +1,12 @@
+//
+//  MBIMImageUtils.h
+//  kordophoned
+//
+//  Created by James Magahern on 12/20/22.
+//  Copyright © 2022 James Magahern. All rights reserved.
+//
+
+#import <Foundation/Foundation.h>
+#import <CoreGraphics/CoreGraphics.h>
+
+extern NSData* MBIMCGImageJPEGRepresentation(CGImageRef imageRef);

kordophone/Bridge/Operations/Utilities/MBIMImageUtils.m

@@ -0,0 +1,37 @@
+//
+//  MBIMImageUtils.m
+//  kordophoned
+//
+//  Created by James Magahern on 12/20/22.
+//  Copyright © 2022 James Magahern. All rights reserved.
+//
+
+#import "MBIMImageUtils.h"
+#import <ImageIO/ImageIO.h>
+
+NSData* MBIMCGImageJPEGRepresentation(CGImageRef imageRef)
+{
+    if (imageRef == NULL) return nil;
+    
+    NSNumber *const DPI = @72.0;
+    NSNumber *const compressionQuality = @0.9;
+    NSDictionary *properties = @{
+        (__bridge NSString *)kCGImagePropertyDPIWidth : DPI,
+        (__bridge NSString *)kCGImagePropertyDPIHeight : DPI,
+        (__bridge NSString *)kCGImageDestinationLossyCompressionQuality : compressionQuality,
+    };
+    
+    bool success = false;
+    NSMutableData *data = [NSMutableData data];
+    if (data) {
+        CGImageDestinationRef imageDestination = CGImageDestinationCreateWithData((CFMutableDataRef)data, CFSTR("public.jpeg"), 1/*count*/, NULL/*options*/);
+        if (imageDestination != NULL) {
+            CGImageDestinationAddImage(imageDestination, imageRef, (__bridge CFDictionaryRef)properties);
+            success = CGImageDestinationFinalize(imageDestination);
+            CFRelease(imageDestination);
+        }
+    }
+
+    return success ? data : nil;
+}
+

kordophone/Categories/IMMessageItem+Encoded.m

@@ -21,16 +21,27 @@
     
     if ([self fileTransferGUIDs]) {
         // Support only images right now
+        NSMutableDictionary *attachmentMetadatas = [NSMutableDictionary dictionary];
         NSMutableArray *filteredFileTransferGUIDs = [NSMutableArray array];
         for (NSString *guid in self.fileTransferGUIDs) {
+            NSMutableDictionary *metadata = [NSMutableDictionary dictionary];
             IMFileTransfer *transfer = [[IMFileTransferCenter sharedInstance] transferForGUID:guid];
             if ([[transfer mimeType] containsString:@"image"]) {
                 [filteredFileTransferGUIDs addObject:guid];
+                
+                if ([transfer attributionInfo] != nil) {
+                    metadata[@"attributionInfo"] = [transfer attributionInfo];
+                }
+            }
+            
+            if (metadata.count) {
+                attachmentMetadatas[guid] = metadata;
             }
         }
         
         if ([filteredFileTransferGUIDs count]) {
             messageDict[@"fileTransferGUIDs"] = filteredFileTransferGUIDs;
+            messageDict[@"attachmentMetadata"] = attachmentMetadatas;
         }
     }