from fastapi import APIRouter, Depends, Path, Query, status
from sqlalchemy.ext.asyncio import AsyncSession

from app.api.dependencies.auth import build_request_context
from app.api.dependencies.database import get_session
from app.api.dependencies.rate_limit import enforce_rate_limit
from app.api.schemas.conversations import FeedbackRequest
from app.api.views.envelope import envelope, list_envelope
from app.core.contracts import RequestContext
from app.core.cursor import parse_cursor
from app.service.conversation_service import ConversationService

router = APIRouter(prefix="/api/v1", tags=["conversations"],
                   dependencies=[Depends(enforce_rate_limit)])


@router.get("/conversations/{session_id}/messages")
async def list_messages(
    session_id: str = Path(min_length=1, max_length=64, pattern=r"^[A-Za-z0-9_-]+$"),
    limit: int = Query(default=20, ge=1, le=100),
    cursor: str | None = Query(default=None),
    context: RequestContext = Depends(build_request_context),  # noqa: B008
    session: AsyncSession = Depends(get_session),  # noqa: B008
) -> dict[str, object]:
    """会话消息列表（文档 §7.3）。

    `cursor` 是文档 §3.8 定义的游标，语义为"取更旧的一页"（记录 ID 边界）。
    校验放在调用 Service 之前：非法游标必须在任何数据访问前变成
    `400 INVALID_CURSOR`，而不是被静默忽略后返回第一页。
    """
    before = parse_cursor(cursor)
    page = await ConversationService(session).messages(
        session_id, context, limit, before=before
    )
    return list_envelope(page, context)


@router.post("/conversation-messages/{message_id}/feedback", status_code=status.HTTP_201_CREATED)
async def create_feedback(
    message_id: int,
    payload: FeedbackRequest,
    context: RequestContext = Depends(build_request_context),  # noqa: B008
    session: AsyncSession = Depends(get_session),  # noqa: B008
) -> dict[str, object]:
    # 与消息列表同理：§3.3 的信封由 Controller 统一套，service 只负责业务数据。
    data = await ConversationService(session).feedback(
        message_id, context, payload.rating, payload.feedback_type, payload.feedback_content)
    return envelope(data, context)