fix flowchart

ai/views/oj.py

@@ -155,7 +155,7 @@ def stream_ai_response(client, system_prompt, user_prompt, on_complete=None):
     """SSE 流式响应生成器，on_complete(full_text) 在流结束时调用"""
     try:
         stream = client.chat.completions.create(
-            model="deepseek-reasoner",
+            model="deepseek-v4-flash",
             messages=[
                 {"role": "system", "content": system_prompt},
                 {"role": "user", "content": user_prompt},
@@ -574,7 +574,7 @@ class AILoginSummaryAPI(APIView):
 
         try:
             completion = client.chat.completions.create(
-                model="deepseek-reasoner",
+                model="deepseek-v4-flash",
                 messages=[
                     {"role": "system", "content": system_prompt},
                     {"role": "user", "content": user_prompt},
@@ -608,7 +608,7 @@ class AIAnalysisAPI(APIView):
             AIAnalysis.objects.create(
                 user=request.user,
                 provider="deepseek",
-                model="deepseek-reasoner",
+                model="deepseek-v4-flash",
                 data={"details": details, "duration": duration},
                 system_prompt=system_prompt,
                 user_prompt="这段时间内的详细数据，每周或每月的数据。",

flowchart/serializers.py

@@ -11,6 +11,9 @@ class CreateFlowchartSubmissionSerializer(serializers.Serializer):
     def validate_mermaid_code(self, value):
         if not value.strip():
             raise serializers.ValidationError("Mermaid代码不能为空")
+        lines = [line for line in value.split("\n") if line.strip()]
+        if len(lines) > 200:
+            raise serializers.ValidationError("流程图过于复杂，请简化后提交")
         return value
 
     def validate_flowchart_data(self, value):
@@ -21,11 +24,13 @@ class CreateFlowchartSubmissionSerializer(serializers.Serializer):
 
 
 class FlowchartSubmissionSerializer(serializers.ModelSerializer):
+    username = serializers.CharField(source="user.username", read_only=True)
+
     class Meta:
         model = FlowchartSubmission
         fields = [
             "id",
-            "user",
+            "username",
             "problem",
             "mermaid_code",
             "flowchart_data",

flowchart/tasks.py

@@ -14,6 +14,7 @@ from .models import FlowchartSubmission, FlowchartSubmissionStatus
 @dramatiq.actor(**DRAMATIQ_WORKER_ARGS(max_retries=3))
 def evaluate_flowchart_task(submission_id):
     """异步AI评分任务"""
+    submission = None
     try:
         submission = FlowchartSubmission.objects.get(id=submission_id)
         
@@ -54,7 +55,7 @@ def evaluate_flowchart_task(submission_id):
         client = get_ai_client()
         
         response = client.chat.completions.create(
-            model="deepseek-reasoner",
+            model="deepseek-v4-flash",
             messages=[
                 {"role": "system", "content": system_prompt},
                 {"role": "user", "content": user_prompt}
@@ -75,7 +76,7 @@ def evaluate_flowchart_task(submission_id):
             submission.ai_suggestions = score_data.get('suggestions', '')
             submission.ai_criteria_details = score_data.get('criteria_details', {})
             submission.ai_provider = 'deepseek'
-            submission.ai_model = 'deepseek-reasoner'
+            submission.ai_model = 'deepseek-v4-flash'
             submission.processing_time = processing_time
             submission.status = FlowchartSubmissionStatus.COMPLETED
             submission.evaluation_time = timezone.now()
@@ -94,11 +95,10 @@ def evaluate_flowchart_task(submission_id):
         )
         
     except Exception as e:
-        # 处理失败
+        if submission is not None:
             submission.status = FlowchartSubmissionStatus.FAILED
             submission.save()
 
-        # 推送错误通知
             from utils.websocket import push_flowchart_evaluation_update
             push_flowchart_evaluation_update(
                 submission_id=str(submission.id),
@@ -106,8 +106,8 @@ def evaluate_flowchart_task(submission_id):
                 data={
                     "type": "flowchart_evaluation_failed",
                     "submission_id": str(submission.id),
-                "error": str(e)
+                    "error": str(e),
-            }
+                },
             )
         raise e
 
@@ -159,11 +159,17 @@ def build_evaluation_prompt(problem):
 def parse_ai_evaluation_response(ai_response):
     """解析AI评分响应，解析失败时抛出异常由调用方处理"""
     import re
+    # 优先匹配代码块中的 JSON，避免贪婪匹配误抓 reasoning 段落
+    code_block = re.search(r'```(?:json)?\s*(\{[\s\S]*?\})\s*```', ai_response, re.DOTALL)
+    if code_block:
+        json_str = code_block.group(1)
+    else:
         json_match = re.search(r'\{.*\}', ai_response, re.DOTALL)
         if not json_match:
             raise ValueError("AI响应中未找到JSON数据")
+        json_str = json_match.group()
 
-    data = json.loads(json_match.group())
+    data = json.loads(json_str)
 
     if "score" not in data or "grade" not in data:
         raise ValueError("AI响应缺少必要字段: score 或 grade")

flowchart/views/oj.py

@@ -80,10 +80,13 @@ class FlowchartSubmissionListAPI(APIView):
             except Problem.DoesNotExist:
                 return self.error("Problem doesn't exist")
             queryset = queryset.filter(problem=problem)
+
         if myself and myself == "1":
             queryset = queryset.filter(user=request.user)
-        if username:
+        elif username:
             queryset = queryset.filter(user__username__icontains=username)
+        elif request.user.is_regular_user():
+            queryset = queryset.filter(user=request.user)
 
         data = self.paginate_data(request, queryset)
         data["results"] = FlowchartSubmissionListSerializer(
@@ -151,7 +154,10 @@ class FlowchartSubmissionDetailAPI(APIView):
         except Problem.DoesNotExist:
             return self.error("Problem doesn't exist")
 
+        try:
             page = int(request.GET.get("page", 0))
+        except ValueError:
+            return self.error("page must be an integer")
         submissions = FlowchartSubmission.objects.filter(
             user=request.user,
             problem=problem,

problem/views/admin.py

@@ -494,7 +494,7 @@ class ProblemFlowchartAIGen(APIView):
         python_code = request.data.get("python", "")
         client = get_ai_client()
         response = client.chat.completions.create(
-            model="deepseek-reasoner",
+            model="deepseek-v4-flash",
             messages=[
                 {
                     "role": "system",