package handler

import (
	"dianshang/internal/service"
	"dianshang/pkg/response"
	"dianshang/pkg/utils"
	"strconv"
	"time"

	"github.com/gin-gonic/gin"
)

// AdminOrderHandler 管理后台订单处理器
type AdminOrderHandler struct {
	orderService *service.OrderService
}

// NewAdminOrderHandler 创建管理后台订单处理器
func NewAdminOrderHandler(orderService *service.OrderService) *AdminOrderHandler {
	return &AdminOrderHandler{
		orderService: orderService,
	}
}

// GetOrderList 获取订单列表
func (h *AdminOrderHandler) GetOrderList(c *gin.Context) {
	page := utils.StringToInt(c.DefaultQuery("page", "1"))
	pageSize := utils.StringToInt(c.DefaultQuery("page_size", "10"))
	status := c.Query("status")
	orderNo := c.Query("order_no")
	userID := utils.StringToUint(c.Query("user_id"))
	startDate := c.Query("start_date")
	endDate := c.Query("end_date")

	if page <= 0 {
		page = 1
	}
	if pageSize <= 0 || pageSize > 100 {
		pageSize = 10
	}

	// 构建查询条件
	conditions := make(map[string]interface{})
	if status != "" {
		conditions["status"] = status
	}
	if orderNo != "" {
		conditions["order_no"] = orderNo
	}
	if userID > 0 {
		conditions["user_id"] = userID
	}
	if startDate != "" {
		conditions["start_date"] = startDate
	}
	if endDate != "" {
		conditions["end_date"] = endDate
	}

	orders, pagination, err := h.orderService.GetOrderListForAdmin(page, pageSize, conditions)
	if err != nil {
		response.ErrorWithMessage(c, response.ERROR, err.Error())
		return
	}

	response.Success(c, gin.H{
		"list":       orders,
		"pagination": pagination,
	})
}

// GetOrderDetail 获取订单详情
func (h *AdminOrderHandler) GetOrderDetail(c *gin.Context) {
	idStr := c.Param("id")
	id, err := strconv.ParseUint(idStr, 10, 32)
	if err != nil {
		response.BadRequest(c, "无效的订单ID")
		return
	}

	order, err := h.orderService.GetOrderDetailForAdmin(uint(id))
	if err != nil {
		response.ErrorWithMessage(c, response.ERROR, "订单不存在")
		return
	}

	response.Success(c, order)
}

// UpdateOrderStatus 更新订单状态
func (h *AdminOrderHandler) UpdateOrderStatus(c *gin.Context) {
	idStr := c.Param("id")
	id, err := strconv.ParseUint(idStr, 10, 32)
	if err != nil {
		response.BadRequest(c, "无效的订单ID")
		return
	}

	var req struct {
		Status int    `json:"status" binding:"required"`
		Remark string `json:"remark"`
	}

	if err := c.ShouldBindJSON(&req); err != nil {
		response.BadRequest(c, "请求参数错误")
		return
	}

	if err := h.orderService.UpdateOrderStatusByAdmin(uint(id), req.Status, req.Remark); err != nil {
		response.ErrorWithMessage(c, response.ERROR, err.Error())
		return
	}

	response.Success(c, nil)
}

// ShipOrder 发货
func (h *AdminOrderHandler) ShipOrder(c *gin.Context) {
	idStr := c.Param("id")
	if idStr == "" {
		response.BadRequest(c, "无效的订单ID")
		return
	}

	orderID, err := strconv.ParseUint(idStr, 10, 32)
	if err != nil {
		response.BadRequest(c, "无效的订单ID")
		return
	}

	var req struct {
		LogisticsCompany string `json:"logistics_company" binding:"required"`
		TrackingNumber   string `json:"tracking_number" binding:"required"`
		Remark           string `json:"remark"`
	}

	if err := c.ShouldBindJSON(&req); err != nil {
		response.BadRequest(c, "请求参数错误")
		return
	}

	if err := h.orderService.ShipOrderByID(uint(orderID), req.LogisticsCompany, req.TrackingNumber); err != nil {
		response.ErrorWithMessage(c, response.ERROR, err.Error())
		return
	}

	response.Success(c, nil)
}

// RefundOrder 退款
func (h *AdminOrderHandler) RefundOrder(c *gin.Context) {
	idStr := c.Param("id")
	id, err := strconv.ParseUint(idStr, 10, 32)
	if err != nil {
		response.BadRequest(c, "无效的订单ID")
		return
	}

	var req struct {
		RefundAmount float64 `json:"refund_amount" binding:"required"`
		RefundReason string  `json:"refund_reason" binding:"required"`
		Remark       string  `json:"remark"`
	}

	if err := c.ShouldBindJSON(&req); err != nil {
		response.BadRequest(c, "请求参数错误")
		return
	}

	// 获取管理员ID
	adminID := uint(0)
	if adminIDValue, exists := c.Get("user_id"); exists {
		adminID = adminIDValue.(uint)
	}

	if err := h.orderService.RefundOrder(uint(id), req.RefundAmount, req.RefundReason, adminID); err != nil {
		response.ErrorWithMessage(c, response.ERROR, err.Error())
		return
	}

	response.Success(c, nil)
}

// CancelOrder 取消订单
func (h *AdminOrderHandler) CancelOrder(c *gin.Context) {
	idStr := c.Param("id")
	id, err := strconv.ParseUint(idStr, 10, 32)
	if err != nil {
		response.BadRequest(c, "无效的订单ID")
		return
	}

	var req struct {
		CancelReason string `json:"cancel_reason" binding:"required"`
		Remark       string `json:"remark"`
	}

	if err := c.ShouldBindJSON(&req); err != nil {
		response.BadRequest(c, "请求参数错误")
		return
	}

	// 获取管理员ID
	adminID := uint(0)
	if adminIDValue, exists := c.Get("user_id"); exists {
		adminID = adminIDValue.(uint)
	}

	if err := h.orderService.CancelOrderByAdmin(uint(id), req.CancelReason, adminID); err != nil {
		response.ErrorWithMessage(c, response.ERROR, err.Error())
		return
	}

	response.Success(c, nil)
}

// GetLogisticsInfo 获取物流信息
func (h *AdminOrderHandler) GetLogisticsInfo(c *gin.Context) {
	orderNo := c.Param("orderNo")
	if orderNo == "" {
		response.BadRequest(c, "无效的订单号")
		return
	}

	logisticsInfo, err := h.orderService.GetLogisticsInfo(orderNo)
	if err != nil {
		response.ErrorWithMessage(c, response.ERROR, err.Error())
		return
	}

	response.Success(c, logisticsInfo)
}

// UpdateOrderStatusNew 更新订单状态（新版本）
func (h *AdminOrderHandler) UpdateOrderStatusNew(c *gin.Context) {
	orderIDStr := c.Param("id")
	orderID, err := strconv.ParseUint(orderIDStr, 10, 32)
	if err != nil {
		response.BadRequest(c, "无效的订单ID")
		return
	}

	var req struct {
		Status int    `json:"status" binding:"required"`
		Reason string `json:"reason"`
	}

	if err := c.ShouldBindJSON(&req); err != nil {
		response.BadRequest(c, "请求参数错误")
		return
	}

	// 获取管理员ID
	adminID := uint(0)
	if id, exists := c.Get("user_id"); exists {
		adminID = id.(uint)
	}

	if err := h.orderService.UpdateOrderStatus(uint(orderID), req.Status, adminID); err != nil {
		response.ErrorWithMessage(c, response.ERROR, err.Error())
		return
	}

	response.Success(c, nil)
}

// BatchUpdateOrderStatus 批量更新订单状态
func (h *AdminOrderHandler) BatchUpdateOrderStatus(c *gin.Context) {
	var req struct {
		OrderIDs []uint `json:"order_ids" binding:"required"`
		Status   int    `json:"status" binding:"required"`
		Reason   string `json:"reason"`
	}

	if err := c.ShouldBindJSON(&req); err != nil {
		response.BadRequest(c, "请求参数错误")
		return
	}

	// 获取管理员ID
	adminID := uint(0)
	if id, exists := c.Get("user_id"); exists {
		adminID = id.(uint)
	}

	if err := h.orderService.BatchUpdateOrderStatus(req.OrderIDs, req.Status, adminID); err != nil {
		response.ErrorWithMessage(c, response.ERROR, err.Error())
		return
	}

	response.Success(c, nil)
}

// ProcessRefund 处理退款
func (h *AdminOrderHandler) ProcessRefund(c *gin.Context) {
	orderIDStr := c.Param("id")
	orderID, err := strconv.ParseUint(orderIDStr, 10, 32)
	if err != nil {
		response.BadRequest(c, "无效的订单ID")
		return
	}

	var req struct {
		RefundAmount float64 `json:"refund_amount" binding:"required"`
		RefundReason string  `json:"refund_reason" binding:"required"`
	}

	if err := c.ShouldBindJSON(&req); err != nil {
		response.BadRequest(c, "请求参数错误")
		return
	}

	// 获取管理员ID
	adminID := uint(0)
	if id, exists := c.Get("user_id"); exists {
		adminID = id.(uint)
	}

	if err := h.orderService.ProcessRefund(uint(orderID), req.RefundAmount, req.RefundReason, adminID); err != nil {
		response.ErrorWithMessage(c, response.ERROR, err.Error())
		return
	}

	response.Success(c, nil)
}

// GetOrderStatistics 获取订单统计
func (h *AdminOrderHandler) GetOrderStatistics(c *gin.Context) {
	statistics, err := h.orderService.GetOrderStatistics()
	if err != nil {
		response.ErrorWithMessage(c, response.ERROR, err.Error())
		return
	}

	response.Success(c, statistics)
}

// GetDailyOrderStatistics 获取每日订单统计
func (h *AdminOrderHandler) GetDailyOrderStatistics(c *gin.Context) {
	daysStr := c.DefaultQuery("days", "7")
	days, err := strconv.Atoi(daysStr)
	if err != nil || days <= 0 {
		days = 7
	}

	statistics, err := h.orderService.GetDailyOrderStatistics(days)
	if err != nil {
		response.ErrorWithMessage(c, response.ERROR, err.Error())
		return
	}

	response.Success(c, statistics)
}

// GetOrdersByDateRange 根据日期范围获取订单
func (h *AdminOrderHandler) GetOrdersByDateRange(c *gin.Context) {
	startDate := c.Query("start_date")
	endDate := c.Query("end_date")
	statusStr := c.DefaultQuery("status", "0")
	pageStr := c.DefaultQuery("page", "1")
	limitStr := c.DefaultQuery("limit", "20")

	status, _ := strconv.Atoi(statusStr)
	page, _ := strconv.Atoi(pageStr)
	limit, _ := strconv.Atoi(limitStr)

	if page <= 0 {
		page = 1
	}
	if limit <= 0 {
		limit = 20
	}

	offset := (page - 1) * limit

	orders, total, err := h.orderService.GetOrdersByDateRange(startDate, endDate, status, offset, limit)
	if err != nil {
		response.ErrorWithMessage(c, response.ERROR, err.Error())
		return
	}

	response.Success(c, gin.H{
		"list":  orders,
		"total": total,
		"page":  page,
		"limit": limit,
	})
}

// ExportOrdersToExcel 导出订单到Excel
func (h *AdminOrderHandler) ExportOrdersToExcel(c *gin.Context) {
	// 获取查询条件
	conditions := make(map[string]interface{})
	
	if startDate := c.Query("start_date"); startDate != "" {
		conditions["start_date"] = startDate
	}
	if endDate := c.Query("end_date"); endDate != "" {
		conditions["end_date"] = endDate
	}
	if statusStr := c.Query("status"); statusStr != "" {
		if status, err := strconv.Atoi(statusStr); err == nil && status > 0 {
			conditions["status"] = status
		}
	}
	if orderNo := c.Query("order_no"); orderNo != "" {
		conditions["order_no"] = orderNo
	}

	exportData, err := h.orderService.ExportOrdersToExcel(conditions)
	if err != nil {
		response.ErrorWithMessage(c, response.ERROR, err.Error())
		return
	}

	// 这里应该生成Excel文件并返回下载链接
	// 暂时返回数据，实际项目中需要使用Excel库生成文件
	response.Success(c, gin.H{
		"data":     exportData,
		"filename": "orders_" + time.Now().Format("20060102_150405") + ".xlsx",
		"message":  "导出成功",
	})
}

// GetOrderTrends 获取订单趋势
func (h *AdminOrderHandler) GetOrderTrends(c *gin.Context) {
	daysStr := c.DefaultQuery("days", "30")
	days, err := strconv.Atoi(daysStr)
	if err != nil || days <= 0 {
		days = 30
	}

	trends, err := h.orderService.GetOrderTrends(days)
	if err != nil {
		response.ErrorWithMessage(c, response.ERROR, err.Error())
		return
	}

	response.Success(c, trends)
}

// GetPendingOrdersCount 获取待处理订单数量
func (h *AdminOrderHandler) GetPendingOrdersCount(c *gin.Context) {
	count, err := h.orderService.GetPendingOrdersCount()
	if err != nil {
		response.ErrorWithMessage(c, response.ERROR, err.Error())
		return
	}

	response.Success(c, gin.H{
		"pending_count": count,
	})
}

// GetOrderSummary 获取订单概览
func (h *AdminOrderHandler) GetOrderSummary(c *gin.Context) {
	// 获取基本统计
	statistics, err := h.orderService.GetOrderStatistics()
	if err != nil {
		response.ErrorWithMessage(c, response.ERROR, err.Error())
		return
	}

	// 获取待处理订单数量
	pendingCount, err := h.orderService.GetPendingOrdersCount()
	if err != nil {
		response.ErrorWithMessage(c, response.ERROR, err.Error())
		return
	}

	// 获取7天趋势
	trends, err := h.orderService.GetOrderTrends(7)
	if err != nil {
		response.ErrorWithMessage(c, response.ERROR, err.Error())
		return
	}

	summary := gin.H{
		"statistics":    statistics,
		"pending_count": pendingCount,
		"trends":        trends,
		"updated_at":    time.Now().Format("2006-01-02 15:04:05"),
	}

	response.Success(c, summary)
}

// BatchProcessOrders 批量处理订单
func (h *AdminOrderHandler) BatchProcessOrders(c *gin.Context) {
	var req struct {
		OrderIDs []uint `json:"order_ids" binding:"required"`
		Action   string `json:"action" binding:"required"` // "ship", "cancel", "refund"
		Data     gin.H  `json:"data"`                      // 额外数据，如物流信息等
	}

	if err := c.ShouldBindJSON(&req); err != nil {
		response.BadRequest(c, "请求参数错误")
		return
	}

	// 获取管理员ID
	adminID := uint(0)
	if id, exists := c.Get("user_id"); exists {
		adminID = id.(uint)
	}

	switch req.Action {
	case "ship":
		// 批量发货
		logisticsCompany, _ := req.Data["logistics_company"].(string)
		trackingNumber, _ := req.Data["tracking_number"].(string)
		
		if logisticsCompany == "" || trackingNumber == "" {
			response.BadRequest(c, "发货需要提供物流公司和运单号")
			return
		}

		for _, orderID := range req.OrderIDs {
			// 这里需要根据订单ID获取订单号
			order, err := h.orderService.GetOrderDetailForAdmin(orderID)
			if err != nil {
				response.ErrorWithMessage(c, response.ERROR, "订单不存在: "+err.Error())
				return
			}
			
			if err := h.orderService.ShipOrder(order.OrderNo, logisticsCompany, trackingNumber); err != nil {
				response.ErrorWithMessage(c, response.ERROR, err.Error())
				return
			}
		}

	case "cancel":
		// 批量取消
		cancelReason, _ := req.Data["cancel_reason"].(string)
		if cancelReason == "" {
			cancelReason = "管理员批量取消"
		}

		for _, orderID := range req.OrderIDs {
			if err := h.orderService.CancelOrderByAdmin(orderID, cancelReason, adminID); err != nil {
				response.ErrorWithMessage(c, response.ERROR, err.Error())
				return
			}
		}

	case "status":
		// 批量更新状态
		status, ok := req.Data["status"].(float64)
		if !ok {
			response.BadRequest(c, "状态更新需要提供status字段")
			return
		}

		if err := h.orderService.BatchUpdateOrderStatus(req.OrderIDs, int(status), adminID); err != nil {
			response.ErrorWithMessage(c, response.ERROR, err.Error())
			return
		}

	default:
		response.BadRequest(c, "不支持的操作类型")
		return
	}

	response.Success(c, nil)
}

// ExportOrders 导出订单
func (h *AdminOrderHandler) ExportOrders(c *gin.Context) {
	startDate := c.Query("start_date")
	endDate := c.Query("end_date")
	status := c.Query("status")

	// 构建查询条件
	conditions := make(map[string]interface{})
	if status != "" {
		conditions["status"] = status
	}
	if startDate != "" {
		conditions["start_date"] = startDate
	}
	if endDate != "" {
		conditions["end_date"] = endDate
	}

	// 获取所有符合条件的订单（不分页）
	orders, _, err := h.orderService.GetOrderListForAdmin(1, 10000, conditions)
	if err != nil {
		response.ErrorWithMessage(c, response.ERROR, err.Error())
		return
	}

	// 设置响应头
	c.Header("Content-Type", "application/vnd.ms-excel")
	c.Header("Content-Disposition", "attachment; filename=orders_"+time.Now().Format("20060102150405")+".csv")

	// 简单的CSV格式导出
	csvData := "订单号,用户ID,订单状态,订单金额,创建时间\n"
	for _, order := range orders {
		csvData += order.OrderNo + "," + 
				  strconv.Itoa(int(order.UserID)) + "," + 
				  strconv.Itoa(order.Status) + "," + 
				  strconv.FormatFloat(order.TotalAmount, 'f', 2, 64) + "," + 
				  order.CreatedAt.Format("2006-01-02 15:04:05") + "\n"
	}

	c.String(200, csvData)
}