wip: carousel media preview view

Session/Media Viewing & Editing/MediaInfoVC+MediaInfoView.swift

@@ -54,7 +54,7 @@ extension MediaInfoVC {
         
         // MARK: - Lifecycle
         
-        init(attachment: Attachment?) {
+        init(attachment: Attachment? = nil) {
             self.attachment = attachment
             
             super.init(frame: CGRect.zero)

Session/Media Viewing & Editing/MediaInfoVC+MediaPreviewView.swift

@@ -59,8 +59,8 @@ extension MediaInfoVC {
         }
 
         private func setUpViewHierarchy() {
-            set(.width, to: 293)
-            set(.height, to: 293)
+            set(.width, to: MediaInfoVC.mediaSize)
+            set(.height, to: MediaInfoVC.mediaSize)
             
             addSubview(mediaView)
             mediaView.pin(to: self)

Session/Media Viewing & Editing/MediaInfoVC.swift

@@ -5,10 +5,14 @@ import SessionUIKit
 import SessionUtilitiesKit
 
 final class MediaInfoVC: BaseVC {
+    internal static let mediaSize: CGFloat = 293
     
     private let attachments: [Attachment]
     private let isOutgoing: Bool
     
+    // MARK: - UI
+    private lazy var mediaInfoView: MediaInfoView = MediaInfoView()
+    
     // MARK: - Initialization
     
     init(attachments: [Attachment], isOutgoing: Bool) {
@@ -36,18 +40,30 @@ final class MediaInfoVC: BaseVC {
             hasCustomBackButton: false
         )
         
+        let mediaStackView: UIStackView = UIStackView()
+        mediaStackView.axis = .horizontal
+        
         attachments.forEach {
             let mediaPreviewView: MediaPreviewView = MediaPreviewView(
                 attachment: $0,
                 isOutgoing: isOutgoing)
-            let mediaInfoView: MediaInfoView = MediaInfoView(attachment: $0)
-            
-            let stackView: UIStackView = UIStackView(arrangedSubviews: [ mediaPreviewView, mediaInfoView ])
-            stackView.axis = .vertical
-            stackView.spacing = Values.largeSpacing
-            
-            self.view.addSubview(stackView)
-            stackView.center(in: self.view)
+            mediaStackView.addArrangedSubview(mediaPreviewView)
         }
+        
+        let scrollView: UIScrollView = UIScrollView()
+        scrollView.isPagingEnabled = true
+        scrollView.set(.width, to: Self.mediaSize)
+        scrollView.set(.height, to: Self.mediaSize)
+        scrollView.contentSize = CGSize(width: Self.mediaSize * CGFloat(attachments.count), height: Self.mediaSize)
+        scrollView.addSubview(mediaStackView)
+        
+        mediaInfoView.update(attachment: attachments[0])
+        
+        let stackView: UIStackView = UIStackView(arrangedSubviews: [ scrollView, mediaInfoView ])
+        stackView.axis = .vertical
+        stackView.spacing = Values.largeSpacing
+        
+        self.view.addSubview(stackView)
+        stackView.center(in: self.view)
     }
 }