feat: restore media description text field

MastodonSDK/Sources/MastodonUI/Scene/ComposeContent/Attachment/AttachmentView.swift

@@ -11,6 +11,8 @@ import SwiftUI
 import Introspect
 import AVKit
 import MastodonAsset
+import MastodonLocalization
+import Introspect
 
 public struct AttachmentView: View {
     
@@ -21,11 +23,35 @@ public struct AttachmentView: View {
     }
 
     public var body: some View {
+        Color.clear.aspectRatio(358.0/232.0, contentMode: .fill)
+            .overlay(
                 ZStack {
                     let image = viewModel.thumbnail ?? .placeholder(color: .secondarySystemFill)
                     Image(uiImage: image)
                         .resizable()
                         .aspectRatio(contentMode: .fill)
+                }
+            )
+            .overlay(
+                ZStack {
+                    Color.clear
+                        .overlay(
+                            VStack(alignment: .leading) {
+                                let placeholder: String = {
+                                    switch viewModel.output {
+                                    case .image: return L10n.Scene.Compose.Attachment.descriptionPhoto
+                                    case .video: return L10n.Scene.Compose.Attachment.descriptionVideo
+                                    case nil:    return ""
+                                    }
+                                }()
+                                Spacer()
+                                TextField(placeholder, text: $viewModel.caption)
+                                    .textFieldStyle(.plain)
+                                    .foregroundColor(.white)
+                                    .placeholder(placeholder, when: viewModel.caption.isEmpty)
+                                    .padding(8)
+                            }
+                        )
                     
                     // loading…
                     if viewModel.output == nil, viewModel.error == nil {
@@ -144,6 +170,32 @@ public struct AttachmentView: View {
                         }
                     }
                 }   // end ZStack
+            )
     }   // end body
     
 }
+
+// https://stackoverflow.com/a/57715771/3797903
+extension View {
+    fileprivate func placeholder<Content: View>(
+        when shouldShow: Bool,
+        alignment: Alignment = .leading,
+        @ViewBuilder placeholder: () -> Content) -> some View {
+
+        ZStack(alignment: alignment) {
+            placeholder().opacity(shouldShow ? 1 : 0)
+            self
+        }
+    }
+    
+    fileprivate func placeholder(
+        _ text: String,
+        when shouldShow: Bool,
+        alignment: Alignment = .leading) -> some View {
+            
+        placeholder(when: shouldShow, alignment: alignment) {
+            Text(text)
+                .foregroundColor(.white.opacity(0.7))
+        }
+    }
+}

MastodonSDK/Sources/MastodonUI/Scene/ComposeContent/Publisher/MastodonStatusPublisher.swift

@@ -125,6 +125,21 @@ extension MastodonStatusPublisher: StatusPublisher {
                 }
                 attachmentIDs.append(attachment.id)
                 
+                let caption = attachmentViewModel.caption
+                guard !caption.isEmpty else { continue }
+                
+                _ = try await api.updateMedia(
+                    domain: authContext.mastodonAuthenticationBox.domain,
+                    attachmentID: attachment.id,
+                    query: .init(
+                        file: nil,
+                        thumbnail: nil,
+                        description: caption,
+                        focus: nil
+                    ),
+                    mastodonAuthenticationBox: authContext.mastodonAuthenticationBox
+                ).singleOutput()
+                
                 // TODO: allow background upload
                 // let attachment = try await attachmentViewModel.upload(context: uploadContext)
                 // let attachmentID = attachment.id

MastodonSDK/Sources/MastodonUI/Scene/ComposeContent/View/ComposeContentView.swift

@@ -219,10 +219,7 @@ extension ComposeContentView {
     var mediaView: some View {
         VStack(spacing: 16) {
             ForEach(viewModel.attachmentViewModels, id: \.self) { attachmentViewModel in
-                Color.clear.aspectRatio(358.0/232.0, contentMode: .fill)
-                    .overlay(
                 AttachmentView(viewModel: attachmentViewModel)
-                    )
                     .clipShape(Rectangle())
                     .badgeView(
                         Button {