docs: 添加 AG-UI 协议规则约束到 apps/AGENTS.md

apps/lib/features/chat/data/services/ag_ui_service.dart

@@ -7,6 +7,7 @@ import '../ai/ai_decision_engine.dart';
 import '../models/ag_ui_event.dart';
 import '../models/tool_result.dart';
 import '../tools/tool_registry.dart';
+import 'mock_history_service.dart';
 
 /// Mock ID 前缀常量
 const _threadIdPrefix = 'thread_';
@@ -25,10 +26,12 @@ typedef EventCallback = void Function(AgUiEvent event);
 class AgUiService {
   EventCallback onEvent;
   final AiDecisionEngine _decisionEngine;
+  final MockHistoryService _historyService;
 
   AgUiService({EventCallback? onEvent})
     : onEvent = onEvent ?? ((_) {}),
-      _decisionEngine = AiDecisionEngine();
+      _decisionEngine = AiDecisionEngine(),
+      _historyService = MockHistoryService();
 
   Future<void> sendMessage(String content) async {
     if (Env.isMockApi) {
@@ -38,6 +41,43 @@ class AgUiService {
     }
   }
 
+  Future<void> loadHistory({DateTime? beforeDate}) async {
+    if (Env.isMockApi) {
+      await _mockLoadHistory(beforeDate: beforeDate);
+    } else {
+      throw UnimplementedError('Real API not implemented');
+    }
+  }
+
+  bool hasEarlierHistory(DateTime fromDate) {
+    return _historyService.hasEarlierHistory(fromDate);
+  }
+
+  Future<void> _mockLoadHistory({DateTime? beforeDate}) async {
+    final threadId = '$_threadIdPrefix${DateTime.now().millisecondsSinceEpoch}';
+    final runId = '$_runIdPrefix${DateTime.now().millisecondsSinceEpoch}';
+
+    onEvent(RunStartedEvent(threadId: threadId, runId: runId));
+
+    DateTime targetDate;
+    if (beforeDate != null) {
+      final prevDate = _historyService.getPreviousDay(beforeDate);
+      if (prevDate == null) {
+        onEvent(RunFinishedEvent(threadId: threadId, runId: runId));
+        return;
+      }
+      targetDate = prevDate;
+    } else {
+      targetDate = _historyService.getLatestHistoryDate() ?? DateTime.now();
+    }
+
+    final messages = _historyService.getHistoryForDay(targetDate);
+
+    onEvent(MessagesSnapshotEvent(messages: messages));
+
+    onEvent(RunFinishedEvent(threadId: threadId, runId: runId));
+  }
+
   Future<void> _mockEventStream(String content) async {
     final threadId = '$_threadIdPrefix${DateTime.now().millisecondsSinceEpoch}';
     final runId = '$_runIdPrefix${DateTime.now().millisecondsSinceEpoch}';