package handlers

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

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

// PageTradeByAdmin 分页查询所有订单
func PageTradeByAdmin(c *fiber.Ctx) error {
	// 检查权限
	_, err := auth.GetAuthCtx(c).PermitAdmin(core.ScopeTradeRead)
	if err != nil {
		return err
	}

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

	// 构建查询语句
	do := q.Trade.Where()
	if req.UserPhone != nil {
		do = do.Where(q.User.As("User").Phone.Eq(*req.UserPhone))
	}
	if req.InnerNo != nil {
		do = do.Where(q.Trade.InnerNo.Eq(*req.InnerNo))
	}
	if req.OuterNo != nil {
		do = do.Where(q.Trade.OuterNo.Eq(*req.OuterNo))
	}
	if req.Method != nil {
		do = do.Where(q.Trade.Method.Eq(*req.Method))
	}
	if req.Platform != nil {
		do = do.Where(q.Trade.Platform.Eq(*req.Platform))
	}
	if req.Status != nil {
		do = do.Where(q.Trade.Status.Eq(*req.Status))
	}
	if req.CreatedAtStart != nil {
		time := u.DateHead(*req.CreatedAtStart)
		do = do.Where(q.Trade.CreatedAt.Gte(time))
	}
	if req.CreatedAtEnd != nil {
		time := u.DateTail(*req.CreatedAtEnd)
		do = do.Where(q.Trade.CreatedAt.Lte(time))
	}

	// 查询用户列表
	list, total, err := q.Trade.
		Joins(q.Trade.User).
		Select(
			q.Trade.ALL,
			q.User.As("User").Phone.As("User__phone"),
			q.User.As("User").Name.As("User__name"),
		).
		Where(do).
		Order(q.Trade.CreatedAt.Desc()).
		FindByPage(req.GetOffset(), req.GetLimit())
	if err != nil {
		return err
	}

	// 返回结果
	return c.JSON(core.PageResp{
		List:  list,
		Total: int(total),
		Page:  req.GetPage(),
		Size:  req.GetSize(),
	})
}

type PageTradeByAdminReq struct {
	core.PageReq
	UserPhone      *string    `json:"user_phone,omitempty"`
	InnerNo        *string    `json:"inner_no,omitempty"`
	OuterNo        *string    `json:"outer_no,omitempty"`
	Method         *int       `json:"method,omitempty"`
	Platform       *int       `json:"platform,omitempty"`
	Status         *int       `json:"status,omitempty"`
	CreatedAtStart *time.Time `json:"created_at_start,omitempty"`
	CreatedAtEnd   *time.Time `json:"created_at_end,omitempty"`
}

// PageTradeOfUserByAdmin 分页查询指定用户的订单
func PageTradeOfUserByAdmin(c *fiber.Ctx) error {
	// 检查权限
	_, err := auth.GetAuthCtx(c).PermitAdmin(core.ScopeTradeReadOfUser)
	if err != nil {
		return err
	}

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

	// 构建查询语句
	do := q.Trade.Where(q.Trade.UserID.Eq(req.UserID))
	if req.InnerNo != nil {
		do = do.Where(q.Trade.InnerNo.Eq(*req.InnerNo))
	}
	if req.OuterNo != nil {
		do = do.Where(q.Trade.OuterNo.Eq(*req.OuterNo))
	}
	if req.Method != nil {
		do = do.Where(q.Trade.Method.Eq(*req.Method))
	}
	if req.Platform != nil {
		do = do.Where(q.Trade.Platform.Eq(*req.Platform))
	}
	if req.Status != nil {
		do = do.Where(q.Trade.Status.Eq(*req.Status))
	}
	if req.CreatedAtStart != nil {
		time := u.DateHead(*req.CreatedAtStart)
		do = do.Where(q.Trade.CreatedAt.Gte(time))
	}
	if req.CreatedAtEnd != nil {
		time := u.DateTail(*req.CreatedAtEnd)
		do = do.Where(q.Trade.CreatedAt.Lte(time))
	}

	// 查询订单列表
	list, total, err := q.Trade.
		Joins(q.Trade.User).
		Select(
			q.Trade.ALL,
			q.User.As("User").Phone.As("User__phone"),
			q.User.As("User").Name.As("User__name"),
		).
		Where(do).
		Order(q.Trade.CreatedAt.Desc()).
		FindByPage(req.GetOffset(), req.GetLimit())
	if err != nil {
		return err
	}

	// 返回结果
	return c.JSON(core.PageResp{
		List:  list,
		Total: int(total),
		Page:  req.GetPage(),
		Size:  req.GetSize(),
	})
}

type PageTradeOfUserByAdminReq struct {
	core.PageReq
	UserID         int32      `json:"user_id" validate:"required"`
	InnerNo        *string    `json:"inner_no,omitempty"`
	OuterNo        *string    `json:"outer_no,omitempty"`
	Method         *int       `json:"method,omitempty"`
	Platform       *int       `json:"platform,omitempty"`
	Status         *int       `json:"status,omitempty"`
	CreatedAtStart *time.Time `json:"created_at_start,omitempty"`
	CreatedAtEnd   *time.Time `json:"created_at_end,omitempty"`
}

// ============================================================

// 创建订单
func TradeCreate(c *fiber.Ctx) error {
	// 检查权限
	authCtx, err := auth.GetAuthCtx(c).PermitUser()
	if err != nil {
		return err
	}
	if authCtx.User.IDType == m.UserIDTypeUnverified {
		return core.NewBizErr("请先实名认证后再购买")
	}

	// 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")
		}
	case m.TradeTypeRecharge:
		if req.Recharge == nil {
			return core.NewBizErr("充值信息不能为空")
		}
	}

	// 处理订单
	var result *s.CreateTradeResult
	switch req.Type {
	case m.TradeTypePurchase:
		result, err = s.Trade.Create(authCtx.User, req.CreateTradeData, req.Resource)
	case m.TradeTypeRecharge:
		result, err = s.Trade.Create(authCtx.User, req.CreateTradeData, req.Recharge)
	}
	if err != nil {
		return core.NewServErr("处理购买产品信息失败", err)
	}

	return c.JSON(result)
}

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

// ============================================================

// 完成订单
func TradeComplete(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
	var req s.TradeRef
	if err := g.Validator.ParseBody(c, &req); err != nil {
		return err
	}

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

	return c.SendStatus(fiber.StatusNoContent)
}

// 管理员完成订单
func TradeCompleteByAdmin(c *fiber.Ctx) error {
	// 检查权限
	_, err := auth.GetAuthCtx(c).PermitAdmin(core.ScopeTradeWriteComplete)
	if err != nil {
		return err
	}

	// 解析请求参数
	var req struct {
		s.TradeRef
		UserID int32 `json:"user_id" validate:"required"`
	}
	if err := g.Validator.ParseBody(c, &req); err != nil {
		return err
	}

	// 获取用户信息
	user, err := s.User.Get(q.Q, req.UserID)
	if err != nil {
		return err
	}

	// 完成订单
	err = s.Trade.CompleteTrade(user, &req.TradeRef)
	if err != nil {
		return err
	}

	return c.SendStatus(fiber.StatusNoContent)
}

// ============================================================

// 取消订单
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.TradeRef)
	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 TradeCancelReq struct {
	s.TradeRef
}

// ============================================================

// 检查订单
func TradeCheck(c *fiber.Ctx) error {
	// 检查权限：sse 接口暂时不检查权限

	// 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.TradeRef)
			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
}

type TradeCheckReq struct {
	s.TradeRef
}