package handler

import (
	"context"
	"encoding/json"
	"net/http"
	"strconv"
	"strings"
	"sync"
	"time"

	"soul-api/internal/database"
	"soul-api/internal/model"
	"soul-api/internal/wechat"

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

// OrdersList GET /api/orders（带用户昵称/头像/手机号，分销佣金按配置比例计算；支持分页 page、pageSize，筛选 status，搜索 search）
func OrdersList(c *gin.Context) {
	db := database.DB()
	page, _ := strconv.Atoi(c.DefaultQuery("page", "1"))
	pageSize, _ := strconv.Atoi(c.DefaultQuery("pageSize", "10"))
	statusFilter := c.Query("status")
	search := strings.TrimSpace(c.Query("search"))
	if page < 1 {
		page = 1
	}
	if pageSize < 1 || pageSize > 100 {
		pageSize = 10
	}

	// 预加载 referral_config，避免订单循环内 N+1 查询
	var refCfgRow model.SystemConfig
	refCfg := (*model.SystemConfig)(nil)
	if err := db.Where("config_key = ?", "referral_config").First(&refCfgRow).Error; err == nil {
		refCfg = &refCfgRow
	}

	// 构建带筛选的查询（count 与 list 共用条件）
	applyOrdersFilter := func(q *gorm.DB) *gorm.DB {
		if statusFilter != "" && statusFilter != "all" {
			if statusFilter == "completed" {
				q = q.Where("status IN ?", []string{"paid", "completed"})
			} else {
				q = q.Where("status = ?", statusFilter)
			}
		}
		if search != "" {
			pattern := "%" + search + "%"
			q = q.Where("order_sn LIKE ? OR id LIKE ? OR user_id IN (SELECT id FROM users WHERE COALESCE(nickname,'') LIKE ? OR COALESCE(phone,'') LIKE ? OR id LIKE ?)",
				pattern, pattern, pattern, pattern, pattern)
		}
		return q
	}

	var total int64
	var totalRevenue, todayRevenue float64
	var orders []model.Order
	var ordersErr error
	var wg sync.WaitGroup

	// 并行：count、营收统计、订单列表
	wg.Add(3)
	go func() {
		defer wg.Done()
		applyOrdersFilter(db.Model(&model.Order{})).Count(&total)
	}()
	go func() {
		defer wg.Done()
		db.Model(&model.Order{}).Select("COALESCE(SUM(amount), 0)").
			Where("status IN ?", []string{"paid", "completed"}).Scan(&totalRevenue)
		todayStart := time.Now().Truncate(24 * time.Hour)
		todayEnd := todayStart.Add(24 * time.Hour)
		db.Model(&model.Order{}).Select("COALESCE(SUM(amount), 0)").
			Where("status IN ? AND created_at >= ? AND created_at < ?", []string{"paid", "completed"}, todayStart, todayEnd).
			Scan(&todayRevenue)
	}()
	go func() {
		defer wg.Done()
		query := applyOrdersFilter(db.Model(&model.Order{}))
		ordersErr = query.Order("created_at DESC").
			Offset((page - 1) * pageSize).
			Limit(pageSize).
			Find(&orders).Error
	}()
	wg.Wait()

	if ordersErr != nil {
		c.JSON(http.StatusOK, gin.H{"success": false, "error": ordersErr.Error(), "orders": []interface{}{}, "total": 0})
		return
	}
	totalPages := int(total) / pageSize
	if int(total)%pageSize > 0 {
		totalPages++
	}
	if len(orders) == 0 {
		c.JSON(http.StatusOK, gin.H{
			"success": true, "orders": []interface{}{},
			"total": total, "page": page, "pageSize": pageSize, "totalPages": totalPages,
		})
		return
	}

	// 收集订单中的 user_id、referrer_id，查用户信息
	userIDs := make(map[string]bool)
	for _, o := range orders {
		if o.UserID != "" {
			userIDs[o.UserID] = true
		}
		if o.ReferrerID != nil && *o.ReferrerID != "" {
			userIDs[*o.ReferrerID] = true
		}
	}
	ids := make([]string, 0, len(userIDs))
	for id := range userIDs {
		ids = append(ids, id)
	}
	var users []model.User
	if len(ids) > 0 {
		db.Where("id IN ?", ids).Find(&users)
	}
	userMap := make(map[string]*model.User)
	for i := range users {
		userMap[users[i].ID] = &users[i]
	}

	getStr := func(s *string) string {
		if s == nil || *s == "" {
			return ""
		}
		return *s
	}

	out := make([]gin.H, 0, len(orders))
	for _, o := range orders {
		// 序列化订单为基础字段
		b, _ := json.Marshal(o)
		var m map[string]interface{}
		_ = json.Unmarshal(b, &m)
		// 用户信息
		if u := userMap[o.UserID]; u != nil {
			m["userNickname"] = getStr(u.Nickname)
			m["userPhone"] = getStr(u.Phone)
			m["userAvatar"] = getStr(u.Avatar)
		} else {
			m["userNickname"] = ""
			m["userPhone"] = ""
			m["userAvatar"] = ""
		}
		// 推荐人信息
		if o.ReferrerID != nil && *o.ReferrerID != "" {
			if u := userMap[*o.ReferrerID]; u != nil {
				m["referrerNickname"] = getStr(u.Nickname)
				m["referrerCode"] = getStr(u.ReferralCode)
			}
		}
		// 分销佣金：仅对已支付且存在推荐人的订单，按 computeOrderCommission（会员 20%/10%，内容 90%）
		status := getStr(o.Status)
		if status == "paid" && o.ReferrerID != nil && *o.ReferrerID != "" {
			var refUser *model.User
			if u := userMap[*o.ReferrerID]; u != nil {
				refUser = u
			}
			m["referrerEarnings"] = computeOrderCommission(db, &o, refUser, refCfg)
		} else {
			m["referrerEarnings"] = nil
		}
		out = append(out, m)
	}
	c.JSON(http.StatusOK, gin.H{
		"success": true, "orders": out,
		"total": total, "page": page, "pageSize": pageSize, "totalPages": totalPages,
		"totalRevenue": totalRevenue, "todayRevenue": todayRevenue,
	})
}

// MiniprogramOrders GET /api/miniprogram/orders 小程序-当前用户订单列表（按 userId 过滤，返回 data）
func MiniprogramOrders(c *gin.Context) {
	userID := c.Query("userId")
	if userID == "" {
		c.JSON(http.StatusOK, gin.H{"success": true, "data": []interface{}{}})
		return
	}
	db := database.DB()
	var orders []model.Order
	if err := db.Where("user_id = ?", userID).Order("created_at DESC").Find(&orders).Error; err != nil {
		c.JSON(http.StatusOK, gin.H{"success": true, "data": []interface{}{}})
		return
	}
	out := make([]gin.H, 0, len(orders))
	for _, o := range orders {
		desc := ""
		if o.Description != nil {
			desc = *o.Description
		}
		productID := ""
		if o.ProductID != nil {
			productID = *o.ProductID
		}
		status := "created"
		if o.Status != nil {
			status = *o.Status
		}
		out = append(out, gin.H{
			"id": o.ID, "order_sn": o.OrderSN, "user_id": o.UserID,
			"product_id": productID, "product_type": o.ProductType,
			"product_name": desc, "section_id": productID,
			"amount": o.Amount, "status": status,
			"created_at": o.CreatedAt,
		})
	}
	c.JSON(http.StatusOK, gin.H{"success": true, "data": out})
}

// AdminOrderRefund PUT /api/admin/orders/refund 管理端-订单退款（仅支持已支付订单，调用微信支付退款）
func AdminOrderRefund(c *gin.Context) {
	var req struct {
		OrderSn string `json:"orderSn" binding:"required"`
		Reason  string `json:"reason"`
	}
	if err := c.ShouldBindJSON(&req); err != nil {
		c.JSON(http.StatusOK, gin.H{"success": false, "error": "缺少订单号"})
		return
	}
	db := database.DB()
	var order model.Order
	if err := db.Where("order_sn = ?", req.OrderSn).First(&order).Error; err != nil {
		c.JSON(http.StatusOK, gin.H{"success": false, "error": "订单不存在"})
		return
	}
	status := ""
	if order.Status != nil {
		status = *order.Status
	}
	if status != "paid" && status != "completed" {
		c.JSON(http.StatusOK, gin.H{"success": false, "error": "仅支持已支付订单退款"})
		return
	}
	transactionID := ""
	if order.TransactionID != nil {
		transactionID = *order.TransactionID
	}
	if transactionID == "" {
		c.JSON(http.StatusOK, gin.H{"success": false, "error": "订单缺少微信支付单号，无法退款"})
		return
	}
	totalCents := int(order.Amount * 100)
	if totalCents < 1 {
		totalCents = 1
	}
	if err := wechat.RefundOrder(context.Background(), order.OrderSN, transactionID, totalCents, req.Reason); err != nil {
		c.JSON(http.StatusOK, gin.H{"success": false, "error": "微信退款失败: " + err.Error()})
		return
	}
	refunded := "refunded"
	updates := map[string]interface{}{"status": refunded}
	if req.Reason != "" {
		updates["refund_reason"] = req.Reason
	}
	if err := db.Model(&order).Updates(updates).Error; err != nil {
		c.JSON(http.StatusOK, gin.H{"success": false, "error": "退款成功但更新订单状态失败: " + err.Error()})
		return
	}
	c.JSON(http.StatusOK, gin.H{"success": true, "message": "退款成功"})
}