Implements attachment previewing

2025-08-24 23:38:35 -07:00
parent 126a4cc55f
commit f0029d02e1
9 changed files with 500 additions and 178 deletions
--- a/kordophone2/Transcript/TranscriptView.swift
+++ b/kordophone2/Transcript/TranscriptView.swift
@@ -0,0 +1,152 @@
+//
+//  TranscriptView.swift
+//  kordophone2
+//
+//  Created by James Magahern on 8/24/25.
+//
+
+import SwiftUI
+
+struct TranscriptView: View
+{
+    @Binding var model: ViewModel
+    
+    @Environment(\.xpcClient) private var xpcClient
+    
+    var body: some View {
+        ScrollView {
+            LazyVStack(spacing: 17.0) {
+                ForEach($model.displayItems.reversed()) { item in
+                    displayItemView(item.wrappedValue)
+                        .id(item.id)
+                        .scaleEffect(CGSize(width: 1.0, height: -1.0))
+                        .transition(
+                            .push(from: .bottom)
+                            .combined(with: .opacity)
+                        )
+                }
+            }
+            .padding()
+        }
+        .scaleEffect(CGSize(width: 1.0, height: -1.0))
+        .task { await watchForMessageListChanges() }
+    }
+    
+    private func watchForMessageListChanges() async {
+        for await event in xpcClient.eventStream() {
+            switch event {
+                case .attachmentDownloaded(let attachmentId):
+                    model.attachmentDownloaded(id: attachmentId)
+                case .messagesUpdated(let conversationId):
+                    if conversationId == model.displayedConversation {
+                        model.setNeedsReload(animated: true)
+                    }
+                case .updateStreamReconnected:
+                    model.setNeedsReload(animated: false)
+                default:
+                    break
+            }
+        }
+    }
+    
+    @ViewBuilder
+    private func displayItemView(_ item: DisplayItem) -> some View {
+        switch item {
+        case .message(let message):
+            TextBubbleItemView(text: message.text, isFromMe: message.isFromMe)
+        case .date(let date):
+            DateItemView(date: date)
+        case .attachment(let attachment):
+            if attachment.isPreviewDownloaded {
+                ImageItemView(
+                    isFromMe: attachment.sender.isMe,
+                    attachment: attachment
+                )
+            } else {
+                PlaceholderImageItemView(
+                    isFromMe: attachment.sender.isMe,
+                    size: attachment.size
+                )
+            }
+        }
+    }
+    
+    // MARK: - Types
+    
+    @Observable
+    class ViewModel
+    {
+        var displayItems: [DisplayItem] = []
+        var displayedConversation: Display.Conversation.ID? = nil
+        
+        internal var needsReload: NeedsReload = .yes(false)
+        internal var messages: [Display.Message]
+
+        init(messages: [Display.Message] = []) {
+            self.messages = messages
+            observeDisplayedConversation()
+            rebuildDisplayItems()
+        }
+        
+        func setNeedsReload(animated: Bool) {
+            needsReload = .yes(animated)
+            Task { @MainActor [weak self] in
+                guard let self else { return }
+                await reloadMessages()
+            }
+        }
+        
+        func attachmentDownloaded(id: String) {
+            // TODO: should be smarter here
+            setNeedsReload(animated: true)
+        }
+        
+        private func observeDisplayedConversation() {
+            withObservationTracking {
+                _ = displayedConversation
+            } onChange: {
+                Task { @MainActor [weak self] in
+                    guard let self else { return }
+                    
+                    setNeedsReload(animated: false)
+                    observeDisplayedConversation()
+                }
+            }
+        }
+        
+        private func reloadMessages() async {
+            guard case .yes(let animated) = needsReload else { return }
+            needsReload = .no
+            
+            guard let displayedConversation else { return }
+            
+            do {
+                let client = XPCClient()
+                let clientMessages = try await client.getMessages(conversationId: displayedConversation)
+                    .map { Display.Message(from: $0) }
+                
+                self.messages = clientMessages
+                self.rebuildDisplayItems(animated: animated)
+            } catch {
+                print("Message fetch error: \(error)")
+            }
+        }
+        
+        // MARK: - Types
+        
+        enum NeedsReload
+        {
+            case no
+            case yes(Bool) // animated
+        }
+    }
+}
+
+#Preview {
+    @Previewable @State var model = TranscriptView.ViewModel(messages: [
+        .init(sender: .me,                 text: "Hello, how are you?"),
+        .init(sender: .counterpart("Bob"), text: "I am doing fine!")
+    ])
+    
+    TranscriptView(model: $model)
+}