initial commit

ios_client/EncryptedChat/Core/MessageCache.swift

@@ -0,0 +1,65 @@
+import Foundation
+
+/// Encrypted local message cache.
+/// Matches Python: chat_core.py message cache (message_cache/{conv_id}.json)
+enum MessageCache {
+
+    /// Save messages for a conversation (encrypted with local storage key)
+    static func save(email: String, convId: String, messages: [[String: Any]], cacheKey: Data?) throws {
+        let dir = try KeyStorage.getKeyDir(email: email).appendingPathComponent("message_cache")
+        try FileManager.default.createDirectory(at: dir, withIntermediateDirectories: true)
+
+        let jsonData = try JSONSerialization.data(withJSONObject: messages)
+
+        let dataToWrite: Data
+        if let cacheKey = cacheKey {
+            dataToWrite = try CryptoUtils.encryptLocal(jsonData, key: cacheKey)
+        } else {
+            dataToWrite = jsonData
+        }
+
+        try dataToWrite.write(to: dir.appendingPathComponent("\(convId).json"), options: .completeFileProtection)
+    }
+
+    /// Load messages for a conversation
+    static func load(email: String, convId: String, cacheKey: Data?) -> [[String: Any]]? {
+        guard let dir = try? KeyStorage.getKeyDir(email: email) else { return nil }
+        let path = dir.appendingPathComponent("message_cache").appendingPathComponent("\(convId).json")
+        guard let raw = try? Data(contentsOf: path) else { return nil }
+
+        let jsonData: Data
+        if let cacheKey = cacheKey {
+            if let decrypted = try? CryptoUtils.decryptLocal(raw, key: cacheKey) {
+                jsonData = decrypted
+            } else {
+                // Plaintext fallback (migration)
+                jsonData = raw
+            }
+        } else {
+            jsonData = raw
+        }
+
+        return try? JSONSerialization.jsonObject(with: jsonData) as? [[String: Any]]
+    }
+
+    /// Search messages in a conversation
+    static func search(email: String, convId: String, query: String, cacheKey: Data?) -> [[String: Any]] {
+        guard let messages = load(email: email, convId: convId, cacheKey: cacheKey) else {
+            return []
+        }
+        let lowerQuery = query.lowercased()
+        return messages.filter { msg in
+            if let text = msg["text"] as? String, text.lowercased().contains(lowerQuery) {
+                return true
+            }
+            return false
+        }
+    }
+
+    /// Delete cache for a conversation
+    static func delete(email: String, convId: String) {
+        guard let dir = try? KeyStorage.getKeyDir(email: email) else { return }
+        let path = dir.appendingPathComponent("message_cache").appendingPathComponent("\(convId).json")
+        try? FileManager.default.removeItem(at: path)
+    }
+}