"""小程序鉴权：微信登录 / 绑定 openid。"""
from __future__ import annotations

from datetime import datetime

from fastapi import APIRouter, Depends, HTTPException, Request
from sqlalchemy.orm import Session

from app.core.auth import get_current_user_by_token
from app.core.database import get_db
from app.core.response import error_response, success_response
from app.crud.user import user_crud
from app.services.issue_user_tokens import issue_tokens_for_user
from app.services.wechat_login_service import resolve_wechat_login_user
from app.services.wechat_mini_auth import (
    WechatMiniAuthError,
    code2session,
    get_phone_number,
)


router = APIRouter(prefix="/mini/auth", tags=["小程序鉴权"])


async def _resolve_user_id(request: Request, db: Session) -> str:
    authorization = request.headers.get("Authorization", "")
    if not authorization.startswith("Bearer "):
        raise HTTPException(status_code=401, detail="未授权")
    token = authorization.replace("Bearer ", "")
    current = await get_current_user_by_token(token=token, db=db)
    user_id = current.get("user_id") or current.get("sub")
    if not user_id:
        raise HTTPException(status_code=401, detail="未授权")
    return user_id


@router.post("/wechat-login", response_model=dict)
async def wechat_login(body: dict, db: Session = Depends(get_db)):
    """微信授权登录：须授权手机号；openid 已绑定也须与账号 phone_no 一致。"""
    login_code = (body.get("loginCode") or "").strip()
    phone_code = (body.get("phoneCode") or "").strip() or None

    try:
        sess = code2session(login_code)
    except WechatMiniAuthError as exc:
        return error_response(400, str(exc))

    if not phone_code:
        return error_response(400, "请授权手机号登录，或使用账号密码登录")

    try:
        phone = get_phone_number(phone_code)
    except WechatMiniAuthError as exc:
        return error_response(400, str(exc))

    user, err_msg, err_code = resolve_wechat_login_user(
        db, openid=sess["openid"], phone=phone
    )
    if err_msg:
        return error_response(err_code or 400, err_msg)

    try:
        data = await issue_tokens_for_user(db, user)
    except ValueError as exc:
        return error_response(403, str(exc))
    return success_response(data)


@router.post("/wechat-bind", response_model=dict)
async def wechat_bind(
    request: Request,
    body: dict,
    db: Session = Depends(get_db),
):
    """密码登录后绑定当前微信 openid（需 Bearer）。"""
    try:
        user_id = await _resolve_user_id(request, db)
    except HTTPException:
        return error_response(401, "未授权")

    login_code = (body.get("loginCode") or "").strip()
    try:
        sess = code2session(login_code)
    except WechatMiniAuthError as exc:
        return error_response(400, str(exc))

    openid = sess["openid"]
    user = user_crud.get(db, user_id)
    if not user or user.del_flag != 0:
        return error_response(401, "用户不存在")

    other = user_crud.get_by_wx_openid(db, openid)
    if other and other.id != user.id:
        return error_response(409, "该微信已绑定其他账号")

    existing_oid = (getattr(user, "wx_openid", None) or "").strip()
    if existing_oid == openid:
        return success_response({"bound": True, "message": "已绑定"})

    if existing_oid and existing_oid != openid:
        return error_response(409, "该账号已绑定其他微信，请联系管理员")

    user.wx_openid = openid
    user.update_time = datetime.now()
    db.add(user)
    db.commit()
    return success_response({"bound": True, "message": "绑定成功"})