initial commit

ios_client/EncryptedChat/ViewModels/ChatViewModel.swift

@@ -0,0 +1,131 @@
+import Foundation
+import SwiftUI
+
+@Observable
+final class ChatViewModel {
+    var messages: [Message] = []
+    var isLoading = false
+    var isSending = false
+    var errorMessage: String?
+    var searchQuery = ""
+    var searchResults: [String] = []  // message IDs matching search
+    var currentSearchIndex = 0
+
+    private var notificationTask: Task<Void, Never>?
+
+    func loadMessages(convId: String, chatClient: ChatClient) async {
+        isLoading = true
+        messages = await chatClient.getMessages(convId: convId, limit: 50)
+        isLoading = false
+
+        // Mark as read
+        let unreadIds = messages.filter { !$0.isMine(currentUserId: await chatClient.userId ?? "") }.map(\.id)
+        if !unreadIds.isEmpty {
+            await chatClient.markRead(convId: convId, messageIds: unreadIds)
+        }
+    }
+
+    func loadOlderMessages(convId: String, chatClient: ChatClient) async {
+        let older = await chatClient.getMessages(convId: convId, limit: 50, offset: messages.count)
+        messages.insert(contentsOf: older, at: 0)
+    }
+
+    func sendMessage(convId: String, text: String, members: [ConversationMember],
+                     chatClient: ChatClient, replyTo: String? = nil) async {
+        guard !text.trimmingCharacters(in: .whitespacesAndNewlines).isEmpty else { return }
+
+        isSending = true
+        errorMessage = nil
+
+        let (success, msg) = await chatClient.sendMessage(
+            convId: convId, text: text, members: members, replyTo: replyTo
+        )
+
+        isSending = false
+
+        if !success {
+            errorMessage = msg
+        } else {
+            // Reload messages to get the sent message
+            await loadMessages(convId: convId, chatClient: chatClient)
+        }
+    }
+
+    func deleteMessage(messageId: String, convId: String, chatClient: ChatClient) async {
+        let success = await chatClient.deleteMessage(messageId: messageId, convId: convId)
+        if success {
+            messages.removeAll { $0.id == messageId }
+        }
+    }
+
+    func search(query: String) {
+        searchQuery = query
+        if query.isEmpty {
+            searchResults = []
+            currentSearchIndex = 0
+            return
+        }
+        let lower = query.lowercased()
+        searchResults = messages.filter { $0.text?.lowercased().contains(lower) == true }.map(\.id)
+        currentSearchIndex = searchResults.isEmpty ? 0 : searchResults.count - 1
+    }
+
+    func nextSearchResult() {
+        guard !searchResults.isEmpty else { return }
+        currentSearchIndex = (currentSearchIndex + 1) % searchResults.count
+    }
+
+    func prevSearchResult() {
+        guard !searchResults.isEmpty else { return }
+        currentSearchIndex = (currentSearchIndex - 1 + searchResults.count) % searchResults.count
+    }
+
+    func startNotificationListener(convId: String, chatClient: ChatClient) {
+        notificationTask?.cancel()
+        notificationTask = Task {
+            for await notification in await chatClient.notifications {
+                await handleNotification(notification, convId: convId, chatClient: chatClient)
+            }
+        }
+    }
+
+    @MainActor
+    private func handleNotification(_ notification: ChatNotification, convId: String, chatClient: ChatClient) {
+        switch notification {
+        case .newMessage(let data):
+            if data["conversation_id"] as? String == convId {
+                if let msg = Task.detached(priority: .userInitiated, operation: {
+                    await chatClient.decryptNotification(data)
+                }) as? Task<Message?, Never> {
+                    Task {
+                        if let message = await msg.value {
+                            messages.append(message)
+                            // Mark as read immediately since we're viewing this conv
+                            await chatClient.markRead(convId: convId, messageIds: [message.id])
+                        }
+                    }
+                }
+            }
+        case .messageDeleted(let data):
+            if let msgId = data["message_id"] as? String {
+                messages.removeAll { $0.id == msgId }
+            }
+        case .messagesRead(let data):
+            if let readUserId = data["user_id"] as? String,
+               let msgIds = data["message_ids"] as? [String] {
+                for i in messages.indices {
+                    if msgIds.contains(messages[i].id) {
+                        messages[i].readBy.insert(readUserId)
+                    }
+                }
+            }
+        default:
+            break
+        }
+    }
+
+    func stop() {
+        notificationTask?.cancel()
+        notificationTask = nil
+    }
+}