package logic

import (
	"context"
	"fmt"
	"math"
	"strconv"

	"lone-services/pkg/modelbase"
	pkgpay "lone-services/pkg/payment"
	"lone-services/pkg/utils"
	payment "lone-services/rpc/payment/pb"
	"lone-services/services/payment/internal/channel"
	"lone-services/services/payment/internal/dao"
	"lone-services/services/payment/internal/model"
	"lone-services/services/payment/internal/svc"

	"github.com/zeromicro/go-zero/core/logx"
)

type PayLogic struct {
	ctx    context.Context
	svcCtx *svc.ServiceContext
	logx.Logger
}

func NewPayLogic(ctx context.Context, svcCtx *svc.ServiceContext) *PayLogic {
	return &PayLogic{
		ctx:    ctx,
		svcCtx: svcCtx,
		Logger: logx.WithContext(ctx),
	}
}

func (l *PayLogic) Pay(in *payment.PayReq) (*payment.Response, error) {
	if in == nil || in.OrderSn == utils.StringEmpty {
		return failResponse(utils.ErrorParams), nil
	}

	loginUser := utils.GetUserFromCtx(l.ctx)
	if loginUser.ID < utils.NumberOne {
		return failResponse(utils.ErrorNoLoginInfo), nil
	}

	client := resolveClient(in.Client, loginUser.ClientCode)
	channelCode := resolveChannel(in.Channel)

	order, err := loadPayableOrder(in.OrderSn, loginUser.ID)
	if err != nil {
		l.Errorf("pay load order: %v", err)
		return failResponse(utils.ErrorNotFund), nil
	}
	if order.Status == dao.PayStatusOk {
		return &payment.Response{
			Code: int32(utils.ErrorRepeatPayment.GetCode()),
			Msg:  utils.ErrorRepeatPayment.GetMsg(),
		}, nil
	}
	if order.Status != dao.PayStatusWait && order.Status != dao.PayStatusIn && order.Status != dao.PayStatusFail {
		return outResponse(utils.Fail, "订单状态不可支付"), nil
	}

	amountFen := yuanToFen(order.PayPrice)
	if amountFen <= 0 {
		return outResponse(utils.Fail, "支付金额无效"), nil
	}

	ch, err := channel.Get(channelCode, client)
	if err != nil {
		l.Errorf("pay channel: %v", err)
		return outResponse(utils.Fail, err.Error()), nil
	}

	prepayReq := &pkgpay.PrepayRequest{
		OutTradeNo:  in.OrderSn,
		Description: "订单支付",
		AmountFen:   amountFen,
		Currency:    "CNY",
		Attach:      in.OrderSn,
	}

	switch channelCode {
	case pkgpay.ChannelWechat:
		openid, oErr := loadOpenID(loginUser.ID)
		if oErr != nil || openid == utils.StringEmpty {
			l.Errorf("pay openid: %v", oErr)
			return outResponse(utils.Fail, "未绑定微信openid"), nil
		}
		prepayReq.OpenID = openid
	case pkgpay.ChannelAlipay, pkgpay.ChannelBank:
		return outResponse(utils.Fail, "支付渠道暂未开通"), nil
	}

	result, err := ch.Prepay(l.ctx, client, prepayReq)
	if err != nil {
		l.Errorf("pay prepay: %v", err)
		return outResponse(utils.Fail, err.Error()), nil
	}

	_ = markOrderPaying(in.OrderSn, channelCode, in.OrderSn)

	return okResponse(result), nil
}

func loadPayableOrder(orderSn string, userID int64) (*dao.OrderPayRow, error) {
	var row dao.OrderPayRow
	err := model.OrderModel{}.Init().GetOne(modelbase.Params{
		Eq: map[string]string{
			"order_sn": orderSn,
		},
	}, &row)
	if err != nil {
		return nil, err
	}
	if row.Id < utils.NumberOne {
		return nil, fmt.Errorf("order not found")
	}
	if row.UserId > 0 && row.UserId != userID {
		return nil, fmt.Errorf("order user mismatch")
	}
	return &row, nil
}

func loadOpenID(userID int64) (string, error) {
	var cred dao.UserCredential
	err := model.UserCredentialModel{}.Init().GetOne(modelbase.Params{
		Eq: map[string]string{
			"user_id":         strconv.FormatInt(userID, 10),
			"credential_type": dao.CredentialTypeOpenid,
			"status":          strconv.Itoa(int(dao.CredentialEnabled)),
		},
	}, &cred)
	if err != nil {
		return "", err
	}
	if cred.Id < utils.NumberOne {
		return "", fmt.Errorf("openid credential not found")
	}
	return cred.Identifier, nil
}

func markOrderPaying(orderSn, channelCode, outTradeNo string) error {
	payType := dao.ChannelToPayType(channelCode)
	updates := map[string]any{
		"status":       dao.PayStatusIn,
		"out_trade_no": outTradeNo,
	}
	if payType > 0 {
		updates["pay_type"] = payType
	}
	_, err := model.OrderModel{}.Init().Edit(modelbase.Params{
		Eq: map[string]string{"order_sn": orderSn},
	}, updates)
	return err
}

func yuanToFen(yuan float64) int64 {
	return int64(math.Round(yuan * 100))
}