package admin

import (
	"encoding/json"
	"fmt"
	"net/http"
	"time"

	"bindbox-game/internal/code"
	"bindbox-game/internal/pkg/core"
	paypkg "bindbox-game/internal/pkg/pay"
	"bindbox-game/internal/pkg/validation"
	"bindbox-game/internal/repository/mysql/model"
)

type createRefundRequest struct {
	OrderNo string `json:"order_no" form:"order_no"`
	Amount  int64  `json:"amount" form:"amount"`
	Reason  string `json:"reason" form:"reason"`
}

type createRefundResponse struct {
	OrderNo string `json:"order_no"`
	Status  string `json:"status"`
}

// CreateRefund 管理端创建退款(占位实现)
// 入参：order_no、amount(分)、reason
// 行为：将订单状态置为已退款，并写入积分流水refund_restore(按订单积分抵扣金额恢复)
// 注意：真实场景需调用微信退款API并根据结果更新状态，本版本为占位保证编译与联调
func (h *handler) CreateRefund() core.HandlerFunc {
	return func(ctx core.Context) {
		req := new(createRefundRequest)
		rsp := new(createRefundResponse)
		if err := ctx.ShouldBindJSON(req); err != nil {
			ctx.AbortWithError(core.Error(http.StatusBadRequest, code.ParamBindError, validation.Error(err)))
			return
		}
		// 查询订单
		order, err := h.readDB.Orders.WithContext(ctx.RequestContext()).Where(h.readDB.Orders.OrderNo.Eq(req.OrderNo)).First()
		if err != nil || order == nil {
			ctx.AbortWithError(core.Error(http.StatusBadRequest, 160001, "order not found"))
			return
		}
		// 计算已退款与可退余额（分）
		ledgers, _ := h.readDB.UserPointsLedger.WithContext(ctx.RequestContext()).ReadDB().Where(h.readDB.UserPointsLedger.RefTable.Eq("orders"), h.readDB.UserPointsLedger.RefID.Eq(order.OrderNo)).Find()
		var refundedSumCents int64
		for _, l := range ledgers {
			if l.Action == "refund_amount" {
				refundedSumCents += l.Points * 100
			}
		}
		refundable := order.ActualAmount - refundedSumCents
		if refundable < 0 {
			refundable = 0
		}
		if req.Amount <= 0 || req.Amount > refundable {
			ctx.AbortWithError(core.Error(http.StatusBadRequest, 160005, fmt.Sprintf("invalid refund amount, max=%d", refundable)))
			return
		}
		// 调用微信真实退款
		wc, err := paypkg.NewWechatPayClient(ctx.RequestContext())
		if err != nil {
			ctx.AbortWithError(core.Error(http.StatusBadRequest, 160006, err.Error()))
			return
		}
		refundNo := fmt.Sprintf("R%s-%d", order.OrderNo, time.Now().Unix())
		refundID, status, err := wc.RefundOrder(ctx.RequestContext(), order.OrderNo, refundNo, req.Amount, order.ActualAmount, req.Reason)
		if err != nil {
			ctx.AbortWithError(core.Error(http.StatusBadRequest, 160007, err.Error()))
			return
		}
		pr := &model.PaymentRefunds{
			OrderID:      order.ID,
			OrderNo:      order.OrderNo,
			RefundNo:     refundNo,
			Channel:      "wechat_jsapi",
			Status:       status,
			AmountRefund: req.Amount,
			Reason:       req.Reason,
			SuccessTime:  time.Now(),
			Raw: func() string {
				b, _ := json.Marshal(map[string]any{"refund_id": refundID, "status": status})
				return string(b)
			}(),
		}
		if err := h.writeDB.PaymentRefunds.WithContext(ctx.RequestContext()).Create(pr); err != nil {
			ctx.AbortWithError(core.Error(http.StatusInternalServerError, 160009, err.Error()))
			return
		}
		// 更新订单状态为已退款
		if req.Amount == order.ActualAmount-refundedSumCents {
			_, err = h.writeDB.Orders.WithContext(ctx.RequestContext()).Where(h.writeDB.Orders.ID.Eq(order.ID)).Updates(map[string]any{
				h.writeDB.Orders.Status.ColumnName().String():    4,
				h.writeDB.Orders.UpdatedAt.ColumnName().String(): time.Now(),
			})
			if err != nil {
				ctx.AbortWithError(core.Error(http.StatusInternalServerError, 160002, err.Error()))
				return
			}
			// 全额退款：恢复订单中使用的优惠券（细化余额与状态逻辑）
			type ocRow struct {
				UserCouponID  int64
				AppliedAmount int64
				DiscountType  int32
				DiscountValue int64
				BalanceAmount int64
			}
			var rows []ocRow
			_ = h.repo.GetDbR().Raw("SELECT oc.user_coupon_id, oc.applied_amount, sc.discount_type, sc.discount_value, uc.balance_amount FROM order_coupons oc JOIN user_coupons uc ON uc.id=oc.user_coupon_id JOIN system_coupons sc ON sc.id=uc.coupon_id WHERE oc.order_id=?", order.ID).Scan(&rows).Error
			for _, r := range rows {
				if r.UserCouponID > 0 && r.AppliedAmount > 0 {
					newBal := r.BalanceAmount + r.AppliedAmount
					if r.DiscountType == 1 { // 直金额券：判断回退后是否全满
						if newBal >= r.DiscountValue {
							_ = h.repo.GetDbW().Exec("UPDATE user_coupons SET balance_amount=?, status=1, used_order_id=0, used_at=NULL WHERE id=?", r.DiscountValue, r.UserCouponID).Error
							newBal = r.DiscountValue
						} else {
							// 若金额未满，维持 status=2 (已使用/使用中)
							_ = h.repo.GetDbW().Exec("UPDATE user_coupons SET balance_amount=?, status=2 WHERE id=?", newBal, r.UserCouponID).Error
						}
					} else { // 满减/折扣券：一律恢复为未使用
						_ = h.repo.GetDbW().Exec("UPDATE user_coupons SET status=1, used_order_id=0, used_at=NULL WHERE id=?", r.UserCouponID).Error
						newBal = 0
					}
					// 记录流水
					ledger := &model.UserCouponLedger{
						UserID:       order.UserID,
						UserCouponID: r.UserCouponID,
						ChangeAmount: r.AppliedAmount,
						BalanceAfter: newBal,
						OrderID:      order.ID,
						Action:       "refund_restore",
						CreatedAt:    time.Now(),
					}
					_ = h.repo.GetDbW().Create(ledger).Error
				}
			}

			// 全额退款：回收中奖资产与奖品库存
			type invRow struct {
				ID       int64
				RewardID int64
			}
			var invs []invRow
			_ = h.repo.GetDbR().Raw("SELECT id, reward_id FROM user_inventory WHERE order_id=? AND status=1", order.ID).Scan(&invs).Error
			for _, inv := range invs {
				// 更新状态为2 (作废)
				_ = h.repo.GetDbW().Exec("UPDATE user_inventory SET status=2, updated_at=NOW(3), remark=CONCAT(IFNULL(remark,''),'|refund_void') WHERE id=?", inv.ID).Error
				// 恢复奖品库存 (ActivityRewardSettings)
				if inv.RewardID > 0 {
					_ = h.repo.GetDbW().Exec("UPDATE activity_reward_settings SET quantity = quantity + 1 WHERE id=?", inv.RewardID).Error
				}
			}

			// 全额退款：取消待发货记录
			_ = h.repo.GetDbW().Exec("UPDATE shipping_records SET status=4, updated_at=NOW(3), remark=CONCAT(IFNULL(remark,''),'|refund_cancel') WHERE order_id=? AND status=1", order.ID).Error

			// 全额退款：回退道具卡
			var itemCardIDs []int64
			_ = h.repo.GetDbR().Raw("SELECT user_item_card_id FROM activity_draw_effects WHERE draw_log_id IN (SELECT id FROM activity_draw_logs WHERE order_id=?)", order.ID).Scan(&itemCardIDs).Error
			for _, icID := range itemCardIDs {
				if icID > 0 {
					_ = h.repo.GetDbW().Exec("UPDATE user_item_cards SET status=1, used_at=NULL, used_draw_log_id=0, used_activity_id=0, used_issue_id=0, updated_at=NOW(3) WHERE id=?", icID).Error
				}
			}
		}
		// 记录积分按比例恢复（幂等增量）
		if order.PointsAmount > 0 {
			restores, _ := h.readDB.UserPointsLedger.WithContext(ctx.RequestContext()).ReadDB().Where(
				h.readDB.UserPointsLedger.RefTable.Eq("orders"),
				h.readDB.UserPointsLedger.RefID.Eq(order.OrderNo),
				h.readDB.UserPointsLedger.Action.Eq("refund_restore"),
			).Find()
			var restoredPointsSum int64
			for _, r := range restores {
				restoredPointsSum += r.Points
			}
			totalRefundedAfter := refundedSumCents + req.Amount
			if totalRefundedAfter > order.ActualAmount {
				totalRefundedAfter = order.ActualAmount
			}
			restoreCentsTarget := (order.PointsAmount * totalRefundedAfter) / order.ActualAmount
			restorePointsTarget := restoreCentsTarget / 100
			toAdd := restorePointsTarget - restoredPointsSum
			maxPoints := order.PointsAmount / 100
			if toAdd < 0 {
				toAdd = 0
			}
			if toAdd > (maxPoints - restoredPointsSum) {
				toAdd = maxPoints - restoredPointsSum
			}
			if toAdd > 0 {
				ledger := &model.UserPointsLedger{
					UserID:   order.UserID,
					Action:   "refund_restore",
					Points:   toAdd,
					RefTable: "orders",
					RefID:    order.OrderNo,
					Remark:   req.Reason,
				}
				if err := h.writeDB.UserPointsLedger.WithContext(ctx.RequestContext()).Create(ledger); err != nil {
					ctx.AbortWithError(core.Error(http.StatusInternalServerError, 160003, err.Error()))
					return
				}
			}
		}
		// 记录退款金额
		amountLedger := &model.UserPointsLedger{
			UserID:   order.UserID,
			Action:   "refund_amount",
			Points:   req.Amount / 100,
			RefTable: "payment_refund",
			RefID:    refundID,
			Remark:   req.Reason,
		}
		if err := h.writeDB.UserPointsLedger.WithContext(ctx.RequestContext()).Create(amountLedger); err != nil {
			ctx.AbortWithError(core.Error(http.StatusInternalServerError, 160004, err.Error()))
			return
		}
		rsp.OrderNo = order.OrderNo
		rsp.Status = "success"
		ctx.Payload(rsp)
	}
}

type listRefundsRequest struct {
	OrderNo string `form:"order_no"`
	Status  string `form:"status"`
	Page    int    `form:"page"`
	Size    int    `form:"size"`
}

type listRefundsResponse struct {
	Total int64            `json:"total"`
	List  []map[string]any `json:"list"`
}

func (h *handler) ListRefunds() core.HandlerFunc {
	return func(ctx core.Context) {
		req := new(listRefundsRequest)
		if err := ctx.ShouldBindQuery(req); err != nil {
			ctx.AbortWithError(core.Error(http.StatusBadRequest, code.ParamBindError, validation.Error(err)))
			return
		}
		if req.Page <= 0 {
			req.Page = 1
		}
		if req.Size <= 0 || req.Size > 100 {
			req.Size = 20
		}
		q := h.readDB.PaymentRefunds.WithContext(ctx.RequestContext()).ReadDB()
		if req.OrderNo != "" {
			q = q.Where(h.readDB.PaymentRefunds.OrderNo.Eq(req.OrderNo))
		}
		if req.Status != "" {
			q = q.Where(h.readDB.PaymentRefunds.Status.Eq(req.Status))
		}
		total, _ := q.Count()
		items, _ := q.Order(h.readDB.PaymentRefunds.ID.Desc()).Limit(req.Size).Offset((req.Page - 1) * req.Size).Find()
		var list []map[string]any
		for _, it := range items {
			list = append(list, map[string]any{
				"refund_no":     it.RefundNo,
				"order_no":      it.OrderNo,
				"status":        it.Status,
				"channel":       it.Channel,
				"amount_refund": it.AmountRefund,
				"reason":        it.Reason,
				"created_at":    it.CreatedAt,
			})
		}
		ctx.Payload(&listRefundsResponse{Total: total, List: list})
	}
}

type getRefundDetailResponse struct {
	Refund map[string]any `json:"refund"`
	Order  map[string]any `json:"order"`
}

func (h *handler) GetRefundDetail() core.HandlerFunc {
	return func(ctx core.Context) {
		refundNo := ctx.Param("refund_no")
		if refundNo == "" {
			ctx.AbortWithError(core.Error(http.StatusBadRequest, code.ParamBindError, "missing refund_no"))
			return
		}
		r, err := h.readDB.PaymentRefunds.WithContext(ctx.RequestContext()).Where(h.readDB.PaymentRefunds.RefundNo.Eq(refundNo)).First()
		if err != nil || r == nil {
			ctx.AbortWithError(core.Error(http.StatusBadRequest, 160008, "refund not found"))
			return
		}
		o, _ := h.readDB.Orders.WithContext(ctx.RequestContext()).Where(h.readDB.Orders.OrderNo.Eq(r.OrderNo)).First()
		resp := &getRefundDetailResponse{
			Refund: map[string]any{
				"refund_no":     r.RefundNo,
				"order_no":      r.OrderNo,
				"status":        r.Status,
				"channel":       r.Channel,
				"amount_refund": r.AmountRefund,
				"reason":        r.Reason,
				"created_at":    r.CreatedAt,
			},
			Order: map[string]any{
				"order_no": func() string {
					if o != nil {
						return o.OrderNo
					}
					return ""
				}(),
				"user_id": func() int64 {
					if o != nil {
						return o.UserID
					}
					return 0
				}(),
				"status": func() int32 {
					if o != nil {
						return o.Status
					}
					return 0
				}(),
				"actual_amount": func() int64 {
					if o != nil {
						return o.ActualAmount
					}
					return 0
				}(),
				"points_amount": func() int64 {
					if o != nil {
						return o.PointsAmount
					}
					return 0
				}(),
			},
		}
		ctx.Payload(resp)
	}
}