chore: 将后端移动到 api/ 目录，准备合并为单仓库

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

api/prompt/api.py

@@ -0,0 +1,193 @@
+import threading
+from typing import List, Optional
+from uuid import UUID
+from ninja import Router
+from ninja.errors import HttpError
+from django.shortcuts import get_object_or_404
+from django.contrib.auth.decorators import login_required
+
+from django.db.models import Count, Prefetch
+from .models import Conversation, Message
+from .utils import get_preceding_user_message
+from .schemas import ConversationOut, MessageOut, PromptHistoryItemOut
+from account.models import RoleChoices
+
+router = Router()
+
+
+@router.get("/conversations/", response=List[ConversationOut])
+@login_required
+def list_conversations(request, task_id: int = None, user_id: int = None):
+    convs = Conversation.objects.select_related("user", "task").annotate(
+        msg_count=Count("messages")
+    )
+    # Normal users can only see their own
+    if request.user.role == "normal":
+        convs = convs.filter(user=request.user)
+    elif user_id:
+        convs = convs.filter(user_id=user_id)
+    if task_id:
+        convs = convs.filter(task_id=task_id)
+    convs = convs.order_by("-msg_count", "-created")
+    return [ConversationOut.from_conv(c) for c in convs]
+
+
+@router.get("/conversations/{conversation_id}/messages/", response=List[MessageOut])
+@login_required
+def list_messages(request, conversation_id: UUID):
+    conv = get_object_or_404(Conversation, id=conversation_id)
+    # Normal users can only see their own
+    if request.user.role == "normal" and conv.user != request.user:
+        return []
+    messages = conv.messages.all()
+    return [
+        {
+            "id": m.id,
+            "role": m.role,
+            "source": m.source,
+            "content": m.content,
+            "code_html": m.code_html,
+            "code_css": m.code_css,
+            "code_js": m.code_js,
+            "prompt_level": m.prompt_level,
+            "created": m.created.isoformat(),
+        }
+        for m in messages
+    ]
+
+
+@router.get("/history/{task_id}", response=List[PromptHistoryItemOut])
+@login_required
+def list_prompt_history(request, task_id: int):
+    """
+    获取当前用户在某任务下的历史对话轮次。
+
+    只返回用户提示词和后一条 assistant 消息中的页面代码，用于前端渲染缩略图。
+    """
+    conversations = Conversation.objects.filter(
+        user=request.user,
+        task_id=task_id,
+    ).prefetch_related(
+        Prefetch("messages", queryset=Message.objects.order_by("created", "id"))
+    )
+
+    items = []
+    for conv in conversations:
+        messages = list(conv.messages.all())
+        for idx, user_msg in enumerate(messages):
+            if user_msg.role != "user":
+                continue
+
+            assistant_msg = None
+            for reply in messages[idx + 1:]:
+                if reply.role == "user":
+                    break
+                if reply.role == "assistant":
+                    assistant_msg = reply
+                    break
+
+            if not assistant_msg:
+                continue
+
+            items.append(
+                (
+                    (user_msg.created, user_msg.id),
+                    {
+                        "user_message_id": user_msg.id,
+                        "assistant_message_id": assistant_msg.id,
+                        "submission_id": assistant_msg.submission_id,
+                        "source": user_msg.source,
+                        "prompt": user_msg.content,
+                        "prompt_level": user_msg.prompt_level,
+                        "code_html": assistant_msg.code_html,
+                        "code_css": assistant_msg.code_css,
+                        "code_js": assistant_msg.code_js,
+                        "created": user_msg.created.isoformat(),
+                    },
+                )
+            )
+
+    return [item for _, item in sorted(items, key=lambda row: row[0])]
+
+
+@router.post("/conversations/{conversation_id}/classify")
+@login_required
+def classify_conversation(request, conversation_id: UUID, force: bool = False):
+    """
+    对对话中所有用户消息进行层级分类（仅管理员和超级管理员可操作，异步执行）
+    """
+    if request.user.role not in (RoleChoices.SUPER, RoleChoices.ADMIN):
+        raise HttpError(403, "没有权限")
+
+    get_object_or_404(Conversation, id=conversation_id)
+
+    from submission.classifier import classify_conversation_messages
+    threading.Thread(
+        target=classify_conversation_messages,
+        args=(conversation_id,),
+        kwargs={"force": force},
+        daemon=True,
+    ).start()
+
+    return {"message": "开始分类"}
+
+
+@router.post("/classify-batch")
+@login_required
+def classify_batch(request, task_id: Optional[int] = None, force: bool = False):
+    """
+    批量分类所有（或指定任务）对话的用户消息层级（仅管理员和超级管理员，异步执行）
+    """
+    if request.user.role not in (RoleChoices.SUPER, RoleChoices.ADMIN):
+        raise HttpError(403, "没有权限")
+
+    qs = Message.objects.filter(role="user")
+    if task_id:
+        qs = qs.filter(conversation__task_id=task_id)
+    if not force:
+        qs = qs.filter(prompt_level__isnull=True)
+
+    ids = list(qs.values_list("id", flat=True))
+
+    from submission.classifier import classify_messages_batch
+    threading.Thread(target=classify_messages_batch, args=(ids,), daemon=True).start()
+
+    return {"message": f"开始分类 {len(ids)} 条消息", "count": len(ids)}
+
+
+@router.delete("/messages/{message_id}/pair")
+@login_required
+def delete_message_pair(request, message_id: int):
+    """
+    Delete a message pair (assistant message + preceding user message) and
+    any linked submission. Only the conversation owner can do this.
+    """
+    asst_msg = get_object_or_404(Message, id=message_id, role="assistant")
+
+    if asst_msg.conversation.user != request.user and request.user.role != RoleChoices.SUPER:
+        raise HttpError(403, "只能删除自己的消息")
+
+    if asst_msg.submission_id and request.user.role != RoleChoices.SUPER:
+        from submission.models import Rating, SubmissionAward
+        has_ratings = Rating.objects.filter(submission_id=asst_msg.submission_id).exists()
+        has_awards = SubmissionAward.objects.filter(submission_id=asst_msg.submission_id).exists()
+        if has_ratings or has_awards:
+            raise HttpError(400, "该消息关联的提交已被评分或获奖，无法删除")
+
+    # Find the preceding user message
+    user_msg = get_preceding_user_message(asst_msg)
+
+    # Delete messages first, then submission
+    submission_id = asst_msg.submission_id  # capture before deletion nulls it
+
+    if user_msg:
+        user_msg.delete()
+    asst_msg.delete()
+
+    submission_deleted = False
+    if submission_id:
+        from submission.models import Submission as SubmissionModel
+        SubmissionModel.objects.filter(id=submission_id).delete()
+        submission_deleted = True
+
+    return {"deleted": True, "submission_deleted": submission_deleted}