"""会话持久化 API：/v1/xtc/sessions

- POST   /v1/xtc/sessions              创建会话
- GET    /v1/xtc/sessions              列出我的会话
- GET    /v1/xtc/sessions/{id}         获取会话详情
- PUT    /v1/xtc/sessions/{id}         更新（标题）
- DELETE /v1/xtc/sessions/{id}         删除
- POST   /v1/xtc/sessions/{id}/messages 追加消息
- GET    /v1/xtc/sessions/{id}/messages 列出消息
"""
from __future__ import annotations

from typing import Optional

from fastapi import APIRouter, Body, Depends, Query, Request

from ..auth import require_access_key
from ..errors import HttpError
from ..services import session_store
from ._common import ok_with_cors

router = APIRouter(prefix="/v1/xtc/sessions", tags=["sessions"])


@router.post("")
async def create_session(
    body: dict = Body(default={}),
    access_key: str = Depends(require_access_key),
):
    sess = session_store.create_session(
        access_key=access_key,
        title=body.get("title"),
        provider=body.get("provider"),
        model=body.get("model"),
    )
    return ok_with_cors({"session": sess})


@router.get("")
async def list_sessions(
    access_key: str = Depends(require_access_key),
    limit: int = Query(default=50, ge=1, le=200),
    offset: int = Query(default=0, ge=0),
):
    items = session_store.list_sessions(access_key=access_key, limit=limit, offset=offset)
    return ok_with_cors({"items": items, "count": len(items)})


@router.get("/{session_id}")
async def get_session(
    session_id: str,
    access_key: str = Depends(require_access_key),
):
    sess = session_store.get_session(session_id, access_key=access_key)
    if not sess:
        raise HttpError(f"session not found: {session_id}", status=404, code="not_found")
    return ok_with_cors({"session": sess})


@router.put("/{session_id}")
async def update_session(
    session_id: str,
    body: dict = Body(default={}),
    access_key: str = Depends(require_access_key),
):
    sess = session_store.update_session(
        session_id, title=body.get("title"), access_key=access_key
    )
    if not sess:
        raise HttpError(f"session not found: {session_id}", status=404, code="not_found")
    return ok_with_cors({"session": sess})


@router.delete("/{session_id}")
async def delete_session(
    session_id: str,
    access_key: str = Depends(require_access_key),
):
    ok = session_store.delete_session(session_id, access_key=access_key)
    if not ok:
        raise HttpError(f"session not found: {session_id}", status=404, code="not_found")
    return ok_with_cors({"deleted": True, "id": session_id})


@router.post("/{session_id}/messages")
async def append_message(
    session_id: str,
    body: dict = Body(default={}),
    access_key: str = Depends(require_access_key),
):
    if not session_store.get_session(session_id, access_key=access_key):
        raise HttpError(f"session not found: {session_id}", status=404, code="not_found")
    role = body.get("role") or "user"
    if role not in ("user", "assistant", "system"):
        raise HttpError("role must be user/assistant/system", status=400, code="bad_request")
    content = body.get("content")
    if content is None:
        raise HttpError("content is required", status=400, code="bad_request")
    msg = session_store.append_message(
        session_id=session_id,
        role=role,
        content=str(content),
        thought=body.get("thought"),
        provider=body.get("provider"),
        model=body.get("model"),
        file_keys=body.get("file_keys"),
    )
    return ok_with_cors({"message": msg})


@router.get("/{session_id}/messages")
async def list_messages(
    session_id: str,
    access_key: str = Depends(require_access_key),
):
    if not session_store.get_session(session_id, access_key=access_key):
        raise HttpError(f"session not found: {session_id}", status=404, code="not_found")
    msgs = session_store.list_messages(session_id)
    return ok_with_cors({"messages": msgs or [], "count": len(msgs or [])})