restore Share/Delete functionality to gallery items in the post multi-attachment world

Signal/src/ViewControllers/MediaDetailViewController.h

@@ -10,6 +10,7 @@ NS_ASSUME_NONNULL_BEGIN
 
 @class GalleryItemBox;
 @class MediaDetailViewController;
+@class TSAttachment;
 
 typedef NS_OPTIONS(NSInteger, MediaGalleryOption) {
     MediaGalleryOptionSliderEnabled = 1 << 0,
@@ -19,7 +20,7 @@ typedef NS_OPTIONS(NSInteger, MediaGalleryOption) {
 @protocol MediaDetailViewControllerDelegate <NSObject>
 
 - (void)mediaDetailViewController:(MediaDetailViewController *)mediaDetailViewController
-    requestDeleteConversationViewItem:(id<ConversationViewItem>)conversationViewItem;
+          requestDeleteAttachment:(TSAttachment *)attachment;
 
 - (void)mediaDetailViewController:(MediaDetailViewController *)mediaDetailViewController
                    isPlayingVideo:(BOOL)isPlayingVideo;

Signal/src/ViewControllers/MediaDetailViewController.m

@@ -348,32 +348,6 @@ NS_ASSUME_NONNULL_BEGIN
     }
 }
 
-- (void)didPressShare:(id)sender
-{
-    OWSFailDebug(@"TODO: support sharing individual attachment, not viewItem");
-
-    OWSLogInfo(@"didPressShare");
-    if (!self.viewItem) {
-        OWSFailDebug(@"share should only be available when a viewItem is present");
-        return;
-    }
-
-    [self.viewItem shareMediaAction];
-}
-
-- (void)didPressDelete:(id)sender
-{
-    OWSFailDebug(@"TODO: support sharing individual attachment, not viewItem");
-
-    OWSLogInfo(@"didPressDelete");
-    if (!self.viewItem) {
-        OWSFailDebug(@"delete should only be available when a viewItem is present");
-        return;
-    }
-
-    [self.delegate mediaDetailViewController:self requestDeleteConversationViewItem:self.viewItem];
-}
-
 - (void)didPressPlayBarButton:(id)sender
 {
     OWSAssertDebug(self.isVideo);

Signal/src/ViewControllers/MediaGalleryViewController.swift

@@ -284,7 +284,7 @@ class MediaGallery: NSObject, MediaGalleryDataSource, MediaTileViewControllerDel
     public func presentDetailView(fromViewController: UIViewController, mediaAttachment: TSAttachment, replacingView: UIView) {
         var galleryItem: MediaGalleryItem?
         uiDatabaseConnection.read { transaction in
-            galleryItem = self.buildGalleryItem(attachment: mediaAttachment, transaction: transaction)!
+            galleryItem = self.buildGalleryItem(attachment: mediaAttachment, transaction: transaction)
         }
 
         guard let initialDetailItem = galleryItem else {
@@ -807,12 +807,19 @@ class MediaGallery: NSObject, MediaGalleryDataSource, MediaTileViewControllerDel
         deletedGalleryItems.formUnion(items)
         dataSourceDelegates.forEach { $0.value?.mediaGalleryDataSource(self, willDelete: items, initiatedBy: initiatedBy) }
 
+        for item in items {
+            self.deletedAttachments.insert(item.attachmentStream)
+        }
+
         self.editingDatabaseConnection.asyncReadWrite { transaction in
             for item in items {
                 let message = item.message
                 let attachment = item.attachmentStream
                 message.removeAttachment(attachment, transaction: transaction)
-                self.deletedAttachments.insert(attachment)
+                if message.attachmentIds.count == 0 {
+                    Logger.debug("removing message after removing last media attachment")
+                    message.remove(with: transaction)
+                }
             }
         }
 

Signal/src/ViewControllers/MediaPageViewController.swift

@@ -277,7 +277,10 @@ class MediaPageViewController: UIPageViewController, UIPageViewControllerDataSou
             owsFailDebug("currentViewController was unexpectedly nil")
             return
         }
-        currentViewController.didPressShare(sender)
+
+        let attachmentStream = currentViewController.galleryItem.attachmentStream
+
+        AttachmentSharing.showShareUI(forAttachment: attachmentStream)
     }
 
     @objc
@@ -508,7 +511,7 @@ class MediaPageViewController: UIPageViewController, UIPageViewControllerDataSou
         self.shouldHideToolbars = !self.shouldHideToolbars
     }
 
-    public func mediaDetailViewController(_ mediaDetailViewController: MediaDetailViewController, requestDelete conversationViewItem: ConversationViewItem) {
+    public func mediaDetailViewController(_ mediaDetailViewController: MediaDetailViewController, requestDelete attachment: TSAttachment) {
         guard let mediaGalleryDataSource = self.mediaGalleryDataSource else {
             owsFailDebug("mediaGalleryDataSource was unexpectedly nil")
             self.presentingViewController?.dismiss(animated: true)
@@ -516,15 +519,8 @@ class MediaPageViewController: UIPageViewController, UIPageViewControllerDataSou
             return
         }
 
-        guard let message = conversationViewItem.interaction as? TSMessage else {
+        guard let galleryItem = self.mediaGalleryDataSource?.galleryItems.first(where: { $0.attachmentStream == attachment }) else {
-            owsFailDebug("unexpected interaction: \(type(of: conversationViewItem))")
+            owsFailDebug("galleryItem was unexpectedly nil")
-            self.presentingViewController?.dismiss(animated: true)
-
-            return
-        }
-
-        guard let galleryItem = self.mediaGalleryDataSource?.galleryItems.first(where: { $0.message == message }) else {
-            owsFailDebug("unexpected interaction: \(type(of: conversationViewItem))")
             self.presentingViewController?.dismiss(animated: true)
 
             return

SignalServiceKit/src/Messages/Interactions/TSMessage.m

@@ -207,8 +207,6 @@ static const NSUInteger OWSMessageSchemaVersion = 4;
             [TSAttachment fetchObjectWithUniqueID:attachmentId transaction:transaction];
         if (attachment) {
             [attachments addObject:attachment];
-        } else {
-            OWSFailDebug(@"Missing attachment for: %@.", attachmentId);
         }
     }
     return [attachments copy];
@@ -221,9 +219,6 @@ static const NSUInteger OWSMessageSchemaVersion = 4;
 
     [self.attachmentIds removeObject:attachment.uniqueId];
 
-    // TODO - Should we delete self if we delete the last attachment?
-    // Or should that depend on whether message.body == nil
-
     [self saveWithTransaction:transaction];
 }
 
@@ -262,8 +257,6 @@ static const NSUInteger OWSMessageSchemaVersion = 4;
     }
 
     TSAttachment *_Nullable attachment = [self attachmentsWithTransaction:transaction].firstObject;
-    OWSAssertDebug(attachment);
-
     if (![OWSMimeTypeOversizeTextMessage isEqualToString:attachment.contentType]
         || ![attachment isKindOfClass:TSAttachmentStream.class]) {
         return nil;