package app

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

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

const (
	shippingFeeThreshold                    = 5
	shippingFeeCents                        = 1000     // 运费金额（分），10 元
	shippingFeeSourceType                   = int32(5) // orders.source_type: 5 = 运费订单
	shippingFeeReasonBelowThreshold          = "below_threshold"
	shippingFeeReasonContainsNonFreeShipping = "contains_non_free_shipping_item"
)

type shippingFeePreorderRequest struct {
	InventoryIDs []int64 `json:"inventory_ids"`
}

type shippingFeePreorderResponse struct {
	OrderNo string `json:"order_no"`
}

type shippingFeeCheckResponse struct {
	NeedFee  bool   `json:"need_fee"`
	Reason   string `json:"reason,omitempty"`
	FeeCents int64  `json:"fee_cents"`
}

func (h *handler) ShippingFeeCheck() core.HandlerFunc {
	return func(ctx core.Context) {
		req := new(shippingFeePreorderRequest)
		rsp := &shippingFeeCheckResponse{FeeCents: shippingFeeCents}
		if err := ctx.ShouldBindJSON(req); err != nil {
			ctx.AbortWithError(core.Error(http.StatusBadRequest, code.ParamBindError, validation.Error(err)))
			return
		}
		if len(req.InventoryIDs) == 0 {
			ctx.AbortWithError(core.Error(http.StatusBadRequest, code.ParamBindError, "inventory_ids 不能为空"))
			return
		}

		userID := int64(ctx.SessionUserInfo().Id)
		needFee, reason, err := h.user.CheckShippingFeeRequirement(ctx.RequestContext(), userID, req.InventoryIDs)
		if err != nil {
			ctx.AbortWithError(core.Error(http.StatusBadRequest, 150002, err.Error()))
			return
		}
		rsp.NeedFee = needFee
		rsp.Reason = reason
		ctx.Payload(rsp)
	}
}

// ShippingFeePreorder 创建运费订单
// @Summary 创建运费订单
// @Description 选中商品命中运费规则时，创建 10 元运费订单并返回 order_no；前端再调用 /pay/wechat/jsapi/preorder 发起支付；无需运费时不应调用
// @Tags APP端.用户
// @Accept json
// @Produce json
// @Security LoginVerifyToken
// @Param user_id path integer true "用户ID"
// @Param RequestBody body shippingFeePreorderRequest true "请求参数：资产ID列表"
// @Success 200 {object} shippingFeePreorderResponse
// @Failure 400 {object} code.Failure
// @Router /api/app/users/{user_id}/inventory/shipping-fee/preorder [post]
func (h *handler) ShippingFeePreorder() core.HandlerFunc {
	return func(ctx core.Context) {
		req := new(shippingFeePreorderRequest)
		rsp := new(shippingFeePreorderResponse)
		if err := ctx.ShouldBindJSON(req); err != nil {
			ctx.AbortWithError(core.Error(http.StatusBadRequest, code.ParamBindError, validation.Error(err)))
			return
		}
		if len(req.InventoryIDs) == 0 {
			ctx.AbortWithError(core.Error(http.StatusBadRequest, code.ParamBindError, "inventory_ids 不能为空"))
			return
		}

		userID := int64(ctx.SessionUserInfo().Id)
		needFee, _, err := h.user.CheckShippingFeeRequirement(ctx.RequestContext(), userID, req.InventoryIDs)
		if err != nil {
			ctx.AbortWithError(core.Error(http.StatusBadRequest, 150002, err.Error()))
			return
		}
		if !needFee {
			ctx.AbortWithError(core.Error(http.StatusBadRequest, 150001, fmt.Sprintf("件数满 %d 件且均非不包邮分类商品，无需支付运费", shippingFeeThreshold)))
			return
		}

		remarkBytes, _ := json.Marshal(req.InventoryIDs)

		// 生成运费订单号（SF + 时间戳 + 用户ID后6位，保证唯一）
		now := time.Now()
		orderNo := fmt.Sprintf("SF%s%06d", now.Format("20060102150405"), userID%1000000)

		// 创建运费订单（source_type=5 区分普通商品订单，status=1 待支付）
		order := &model.Orders{
			UserID:         userID,
			OrderNo:        orderNo,
			SourceType:     shippingFeeSourceType,
			TotalAmount:    shippingFeeCents,
			DiscountAmount: 0,
			PointsAmount:   0,
			ActualAmount:   shippingFeeCents,
			Status:         1,
			IsConsumed:     0,
			Remark:         string(remarkBytes),
		}
		if err := h.writeDB.Orders.WithContext(ctx.RequestContext()).
			Omit(h.writeDB.Orders.PaidAt, h.writeDB.Orders.CancelledAt).
			Create(order); err != nil {
			ctx.AbortWithError(core.Error(http.StatusBadRequest, 150002, "创建运费订单失败: "+err.Error()))
			return
		}

		rsp.OrderNo = orderNo
		ctx.Payload(rsp)
	}
}