package handlers

import (
	"bufio"
	"fmt"
	"log/slog"
	"platform/pkg/env"
	"platform/web/auth"
	"platform/web/core"
	g "platform/web/globals"
	m "platform/web/models"
	s "platform/web/services"
	"time"

	"github.com/gofiber/fiber/v2"
	"github.com/valyala/fasthttp"
)

type TradeCreateReq struct {
	s.CreateTradeData
	Type     m.TradeType            `json:"type" validate:"required"`
	Resource *s.CreateResourceData  `json:"resource,omitempty"`
	Recharge *s.RechargeProductInfo `json:"recharge,omitempty"`
}

type TradeCreateResp struct {
	PayUrl  string `json:"pay_url"`
	TradeNo string `json:"trade_no"`
}

func TradeCreate(c *fiber.Ctx) error {
	// 检查权限
	authCtx, err := auth.GetAuthCtx(c).PermitUser()
	if err != nil {
		return err
	}

	// 解析请求参数
	req := new(TradeCreateReq)
	if err := g.Validator.ParseBody(c, req); err != nil {
		return err
	}

	switch req.Type {
	case m.TradeTypePurchase:
		if req.Resource == nil {
			return core.NewBizErr("购买信息不能为空")
		}
		req.Product = req.Resource
	case m.TradeTypeRecharge:
		if req.Recharge == nil {
			return core.NewBizErr("充值信息不能为空")
		}
		req.Product = req.Recharge
	}

	// 创建交易
	result, err := s.Trade.CreateTrade(authCtx.User.ID, time.Now(), &req.CreateTradeData)
	if err != nil {
		slog.Error("创建交易失败", "error", err)
		return c.Status(fiber.StatusInternalServerError).JSON(fiber.Map{"error": "创建交易失败"})
	}

	return c.JSON(&TradeCreateResp{
		PayUrl:  result.PaymentUrl,
		TradeNo: result.TradeNo,
	})
}

type TradeCompleteReq struct {
	s.ModifyTradeData
}

func TradeComplete(c *fiber.Ctx) error {
	// 检查权限
	_, err := auth.GetAuthCtx(c).PermitUser()
	if err != nil {
		return err
	}

	// 解析请求参数
	req := new(TradeCompleteReq)
	if err := g.Validator.ParseBody(c, req); err != nil {
		return err
	}

	// 检查订单状态
	err = s.Trade.CompleteTrade(&req.ModifyTradeData)
	if err != nil {
		return err
	}

	return c.SendStatus(fiber.StatusNoContent)
}

type TradeCancelReq struct {
	s.ModifyTradeData
}

func TradeCancel(c *fiber.Ctx) error {
	// 检查权限
	_, err := auth.GetAuthCtx(c).PermitUser()
	if err != nil {
		return err
	}

	// 解析请求参数
	req := new(TradeCancelReq)
	if err := g.Validator.ParseBody(c, req); err != nil {
		return err
	}

	// 取消交易
	err = s.Trade.CancelTrade(&req.ModifyTradeData, time.Now())
	if err != nil {
		slog.Error("取消交易失败", "trade_no", req.TradeNo, "error", err)
		return c.Status(fiber.StatusInternalServerError).JSON(fiber.Map{"error": "取消交易失败"})
	}

	return c.SendStatus(fiber.StatusNoContent)
}

type TradeCheckReq struct {
	s.ModifyTradeData
}

func TradeCheck(c *fiber.Ctx) error {
	// 解析请求参数
	req := new(TradeCheckReq)
	if err := g.Validator.ParseQuery(c, req); err != nil {
		return err
	}

	c.Set(fiber.HeaderContentType, "text/event-stream")
	c.Set(fiber.HeaderCacheControl, "no-cache")
	c.Set(fiber.HeaderConnection, "keep-alive")
	c.Set(fiber.HeaderTransferEncoding, "chunked")
	c.Context().SetBodyStreamWriter(fasthttp.StreamWriter(func(w *bufio.Writer) {

		expire := env.TradeExpire
		interval := 5
		for range expire / interval {
			// 检查订单状态
			result, err := s.Trade.CheckTrade(&req.ModifyTradeData)
			if err != nil {
				slog.Error("检查订单状态失败", "trade_no", req.TradeNo, "error", err)
				return
			}

			// 写入订单状态
			_, err = fmt.Fprintf(w, "data: %d\n\n", result.Status)
			if err != nil {
				slog.Error("写入订单状态失败", "trade_no", req.TradeNo, "error", err)
				return
			}

			err = w.Flush()
			if err != nil {
				return
			}

			// 当订单离开支付状态后结束查询
			if result.Status != m.TradeStatusPending {
				return
			}

			time.Sleep(time.Duration(interval) * time.Second)
		}
	}))

	return nil
}