"""
统一支付服务门面
提供统一的支付接口，屏蔽微信/支付宝的底层差异
"""
import logging
from typing import Dict, Optional

from .config import PaymentConfig
from .wechat_pay import WeChatPayClient
from .alipay_pay import AlipayClient
from .schemas import PaymentResult, NotifyResult, PaymentStatus
from .exceptions import PaymentError, PaymentConfigError

logger = logging.getLogger(__name__)

# 支持的支付方式
PAYMENT_METHOD_WECHAT = "wechat"
PAYMENT_METHOD_ALIPAY = "alipay"
SUPPORTED_METHODS = {PAYMENT_METHOD_WECHAT, PAYMENT_METHOD_ALIPAY}


class PaymentService:
    """
    统一支付服务

    使用方式:
        config = PaymentConfig.from_env()
        payment_service = PaymentService(config)

        # 创建支付订单
        result = payment_service.create_payment("wechat", order_no, 9900, "高级版套餐")

        # 处理回调
        notify = payment_service.handle_wechat_notify(headers, body)

        # 查询状态
        status = payment_service.query_payment("wechat", order_no)
    """

    def __init__(self, config: PaymentConfig):
        self._config = config
        self._wechat_client: Optional[WeChatPayClient] = None
        self._alipay_client: Optional[AlipayClient] = None

    @property
    def wechat_client(self) -> WeChatPayClient:
        """获取微信支付客户端（懒加载）"""
        if self._wechat_client is None:
            self._wechat_client = WeChatPayClient(self._config.wechat)
        return self._wechat_client

    @property
    def alipay_client(self) -> AlipayClient:
        """获取支付宝客户端（懒加载）"""
        if self._alipay_client is None:
            self._alipay_client = AlipayClient(self._config.alipay)
        return self._alipay_client

    def create_payment(
        self,
        method: str,
        out_trade_no: str,
        total_amount: int,
        description: str,
    ) -> PaymentResult:
        """
        创建支付订单

        Args:
            method: 支付方式 (wechat / alipay)
            out_trade_no: 商户订单号
            total_amount: 金额（单位：分）
            description: 商品描述

        Returns:
            PaymentResult
        """
        self._validate_method(method)

        if method == PAYMENT_METHOD_WECHAT:
            return self.wechat_client.create_app_order(
                out_trade_no=out_trade_no,
                total_amount=total_amount,
                description=description,
            )
        else:
            return self.alipay_client.create_app_order(
                out_trade_no=out_trade_no,
                total_amount=total_amount,
                subject=description,
            )

    def handle_wechat_notify(
        self, headers: Dict[str, str], body: str
    ) -> NotifyResult:
        """
        处理微信支付异步回调通知

        Args:
            headers: 请求头
            body: 请求体

        Returns:
            NotifyResult
        """
        return self.wechat_client.verify_notify(headers=headers, body=body)

    def handle_alipay_notify(self, params: Dict[str, str]) -> NotifyResult:
        """
        处理支付宝异步回调通知

        Args:
            params: 回调参数

        Returns:
            NotifyResult
        """
        return self.alipay_client.verify_notify(params=params)

    def query_payment(self, method: str, out_trade_no: str) -> PaymentStatus:
        """
        查询支付订单状态

        Args:
            method: 支付方式 (wechat / alipay)
            out_trade_no: 商户订单号

        Returns:
            PaymentStatus
        """
        self._validate_method(method)

        if method == PAYMENT_METHOD_WECHAT:
            return self.wechat_client.query_order(out_trade_no=out_trade_no)
        else:
            return self.alipay_client.query_order(out_trade_no=out_trade_no)

    def close_payment(self, method: str, out_trade_no: str) -> bool:
        """
        关闭支付订单

        Args:
            method: 支付方式 (wechat / alipay)
            out_trade_no: 商户订单号

        Returns:
            是否关闭成功
        """
        self._validate_method(method)

        if method == PAYMENT_METHOD_WECHAT:
            return self.wechat_client.close_order(out_trade_no=out_trade_no)
        else:
            return self.alipay_client.close_order(out_trade_no=out_trade_no)

    def is_method_available(self, method: str) -> bool:
        """检查指定支付方式是否可用"""
        if method == PAYMENT_METHOD_WECHAT:
            return self._config.wechat.is_configured
        elif method == PAYMENT_METHOD_ALIPAY:
            if getattr(self._config, "alipay_under_development", True):
                return False
            return self._config.alipay.is_configured
        return False

    @staticmethod
    def _validate_method(method: str):
        """验证支付方式"""
        if method not in SUPPORTED_METHODS:
            raise PaymentError(
                f"不支持的支付方式: {method}，支持的方式: {', '.join(SUPPORTED_METHODS)}",
                code="UNSUPPORTED_METHOD",
            )