package handler

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

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

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

var paidStatuses = []string{"paid", "completed", "success"}

// AdminDashboardStats GET /api/admin/dashboard/stats
// 轻量聚合：总用户、付费订单数、付费用户数、总营收、转化率（无订单/用户明细）
func AdminDashboardStats(c *gin.Context) {
	db := database.DB()
	var (
		totalUsers     int64
		paidOrderCount int64
		totalRevenue   float64
		paidUserCount  int64
	)
	var wg sync.WaitGroup
	wg.Add(4)
	go func() { defer wg.Done(); db.Model(&model.User{}).Count(&totalUsers) }()
	go func() { defer wg.Done(); db.Model(&model.Order{}).Where("status IN ?", paidStatuses).Count(&paidOrderCount) }()
	go func() {
		defer wg.Done()
		db.Model(&model.Order{}).Where("status IN ?", paidStatuses).
			Select("COALESCE(SUM(amount), 0)").Scan(&totalRevenue)
	}()
	go func() {
		defer wg.Done()
		db.Table("orders").Where("status IN ?", paidStatuses).
			Select("COUNT(DISTINCT user_id)").Scan(&paidUserCount)
	}()
	wg.Wait()
	conversionRate := 0.0
	if totalUsers > 0 && paidUserCount > 0 {
		conversionRate = float64(paidUserCount) / float64(totalUsers) * 100
	}
	c.JSON(http.StatusOK, gin.H{
		"success":        true,
		"totalUsers":     totalUsers,
		"paidOrderCount": paidOrderCount,
		"paidUserCount":  paidUserCount,
		"totalRevenue":   totalRevenue,
		"conversionRate": conversionRate,
	})
}

// AdminDashboardRecentOrders GET /api/admin/dashboard/recent-orders?limit=10
func AdminDashboardRecentOrders(c *gin.Context) {
	db := database.DB()
	limit := 5
	if l := c.Query("limit"); l != "" {
		if n, err := strconv.Atoi(l); err == nil && n >= 1 && n <= 20 {
			limit = n
		}
	}
	var recentOrders []model.Order
	db.Where("status IN ?", paidStatuses).Order("created_at DESC").Limit(limit).Find(&recentOrders)
	c.JSON(http.StatusOK, gin.H{"success": true, "recentOrders": buildRecentOrdersOut(db, recentOrders)})
}

// AdminDashboardNewUsers GET /api/admin/dashboard/new-users
func AdminDashboardNewUsers(c *gin.Context) {
	db := database.DB()
	var newUsers []model.User
	db.Model(&model.User{}).Order("created_at DESC").Limit(10).Find(&newUsers)
	c.JSON(http.StatusOK, gin.H{"success": true, "newUsers": buildNewUsersOut(newUsers)})
}

// AdminDashboardOverview GET /api/admin/dashboard/overview
// 数据概览：总用户、付费订单数、付费用户数、总营收、转化率、最近订单、新用户
// 优化：6 组查询并行执行，减少总耗时
func AdminDashboardOverview(c *gin.Context) {
	db := database.DB()

	var (
		totalUsers     int64
		paidOrderCount int64
		totalRevenue   float64
		paidUserCount  int64
		recentOrders   []model.Order
		newUsers       []model.User
	)
	var wg sync.WaitGroup
	wg.Add(6)

	go func() {
		defer wg.Done()
		db.Model(&model.User{}).Count(&totalUsers)
	}()
	go func() {
		defer wg.Done()
		db.Model(&model.Order{}).Where("status IN ?", paidStatuses).Count(&paidOrderCount)
	}()
	go func() {
		defer wg.Done()
		db.Model(&model.Order{}).Where("status IN ?", paidStatuses).
			Select("COALESCE(SUM(amount), 0)").Scan(&totalRevenue)
	}()
	go func() {
		defer wg.Done()
		db.Table("orders").Where("status IN ?", paidStatuses).
			Select("COUNT(DISTINCT user_id)").Scan(&paidUserCount)
	}()
	go func() {
		defer wg.Done()
		db.Where("status IN ?", paidStatuses).
			Order("created_at DESC").Limit(5).Find(&recentOrders)
	}()
	go func() {
		defer wg.Done()
		db.Model(&model.User{}).Order("created_at DESC").Limit(10).Find(&newUsers)
	}()
	wg.Wait()

	conversionRate := 0.0
	if totalUsers > 0 && paidUserCount > 0 {
		conversionRate = float64(paidUserCount) / float64(totalUsers) * 100
	}

	recentOut := buildRecentOrdersOut(db, recentOrders)
	newOut := buildNewUsersOut(newUsers)

	c.JSON(http.StatusOK, gin.H{
		"success":         true,
		"totalUsers":      totalUsers,
		"paidOrderCount":  paidOrderCount,
		"paidUserCount":   paidUserCount,
		"totalRevenue":    totalRevenue,
		"conversionRate":  conversionRate,
		"recentOrders":    recentOut,
		"newUsers":        newOut,
	})
}

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

func buildRecentOrdersOut(db *gorm.DB, recentOrders []model.Order) []gin.H {
	if len(recentOrders) == 0 {
		return nil
	}
	userIDs := make(map[string]bool)
	for _, o := range recentOrders {
		if o.UserID != "" {
			userIDs[o.UserID] = true
		}
	}
	ids := make([]string, 0, len(userIDs))
	for id := range userIDs {
		ids = append(ids, id)
	}
	var users []model.User
	db.Where("id IN ?", ids).Find(&users)
	userMap := make(map[string]*model.User)
	for i := range users {
		userMap[users[i].ID] = &users[i]
	}
	out := make([]gin.H, 0, len(recentOrders))
	for _, o := range recentOrders {
		b, _ := json.Marshal(o)
		var m map[string]interface{}
		_ = json.Unmarshal(b, &m)
		if u := userMap[o.UserID]; u != nil {
			m["userNickname"] = dashStr(u.Nickname)
			m["userAvatar"] = dashStr(u.Avatar)
		} else {
			m["userNickname"] = ""
			m["userAvatar"] = ""
		}
		out = append(out, m)
	}
	return out
}

// AdminBalanceSummary GET /api/admin/balance/summary
// 汇总代付金额（product_type 为 gift_pay 或 gift_pay_batch 的已支付订单），用于 Dashboard 显示「含代付 ¥xx」
func AdminBalanceSummary(c *gin.Context) {
	db := database.DB()
	var totalGifted float64
	db.Model(&model.Order{}).Where("product_type IN ? AND status IN ?", []string{"gift_pay", "gift_pay_batch"}, paidStatuses).
		Select("COALESCE(SUM(amount), 0)").Scan(&totalGifted)
	c.JSON(http.StatusOK, gin.H{"success": true, "data": gin.H{"totalGifted": totalGifted}})
}

// AdminDashboardMerchantBalance GET /api/admin/dashboard/merchant-balance
// 查询微信商户号实时余额（可用余额、待结算余额），用于看板展示
// 注意：普通商户可能需向微信申请开通权限，未开通时返回 error
func AdminDashboardMerchantBalance(c *gin.Context) {
	bal, err := wechat.QueryMerchantBalance("BASIC")
	if err != nil {
		c.JSON(http.StatusOK, gin.H{
			"success": false,
			"error":   err.Error(),
			"message": "查询商户余额失败，可能未开通权限（请联系微信支付运营申请）",
		})
		return
	}
	c.JSON(http.StatusOK, gin.H{
		"success":         true,
		"availableAmount": bal.AvailableAmount, // 单位：分
		"pendingAmount":   bal.PendingAmount,   // 单位：分
	})
}

// AdminDashboardLeads GET /api/admin/dashboard/leads?limit=20
// 管理端-首页客资中心：聚合 ckb_lead_records（链接卡若留资）+ ckb_submit_records（join/match），
// 联表 users 补齐头像/昵称，按时间倒序，每条包含联系方式（phone/wechatId）与来源。
func AdminDashboardLeads(c *gin.Context) {
	db := database.DB()
	limit := 20
	if l := c.Query("limit"); l != "" {
		if n, err := strconv.Atoi(l); err == nil && n >= 1 && n <= 100 {
			limit = n
		}
	}
	search := c.Query("search")

	// 1. ckb_lead_records（链接卡若 / 文章@）
	var leads []model.CkbLeadRecord
	qLead := db.Model(&model.CkbLeadRecord{}).Order("created_at DESC")
	if search != "" {
		qLead = qLead.Where("nickname LIKE ? OR phone LIKE ? OR name LIKE ? OR wechat_id LIKE ?",
			"%"+search+"%", "%"+search+"%", "%"+search+"%", "%"+search+"%")
	}
	qLead.Limit(limit).Find(&leads)

	// 2. ckb_submit_records（join/match）
	var submits []model.CkbSubmitRecord
	qSub := db.Model(&model.CkbSubmitRecord{}).Order("created_at DESC")
	if search != "" {
		qSub = qSub.Where("nickname LIKE ? OR params LIKE ?", "%"+search+"%", "%"+search+"%")
	}
	qSub.Limit(limit).Find(&submits)

	// 收集所有 userID 关联用户信息
	userIDs := make(map[string]bool)
	for _, l := range leads {
		if l.UserID != "" {
			userIDs[l.UserID] = true
		}
	}
	for _, s := range submits {
		if s.UserID != "" {
			userIDs[s.UserID] = true
		}
	}
	ids := make([]string, 0, len(userIDs))
	for id := range userIDs {
		ids = append(ids, id)
	}
	var users []model.User
	if len(ids) > 0 {
		db.Select("id", "nickname", "avatar", "phone", "wechat_id", "is_vip", "tags", "ckb_tags").Where("id IN ?", ids).Find(&users)
	}
	userMap := make(map[string]*model.User)
	for i := range users {
		userMap[users[i].ID] = &users[i]
	}

	// 统计
	var totalLeads, totalSubmits int64
	db.Model(&model.CkbLeadRecord{}).Count(&totalLeads)
	db.Model(&model.CkbSubmitRecord{}).Count(&totalSubmits)
	var withPhone int64
	db.Model(&model.CkbLeadRecord{}).Where("phone != '' AND phone IS NOT NULL").Count(&withPhone)

	// 去重统计：按 userId/phone/wechatId 聚合重复次数
	dupCounts := make(map[string]int64)
	for _, l := range leads {
		key := l.UserID
		if key == "" {
			key = l.Phone
		}
		if key == "" {
			key = l.WechatID
		}
		if key != "" {
			if _, ok := dupCounts[key]; !ok {
				var cnt int64
				q := db.Model(&model.CkbLeadRecord{})
				if l.UserID != "" {
					q = q.Where("user_id = ?", l.UserID)
				} else if l.Phone != "" {
					q = q.Where("phone = ?", l.Phone)
				} else {
					q = q.Where("wechat_id = ?", l.WechatID)
				}
				q.Count(&cnt)
				dupCounts[key] = cnt
			}
		}
	}

	// 构造输出
	type leadOut struct {
		SortTime time.Time
		Data     gin.H
	}
	all := make([]leadOut, 0, len(leads)+len(submits))
	for _, l := range leads {
		u := userMap[l.UserID]
		avatar := ""
		userNickname := l.Nickname
		if u != nil {
			avatar = dashStr(u.Avatar)
			if dashStr(u.Nickname) != "" {
				userNickname = dashStr(u.Nickname)
			}
		}
		sourceLabel := "链接卡若"
		if l.Source == "article_mention" {
			sourceLabel = "文章@"
		} else if l.Source == "index_link_button" {
			sourceLabel = "首页链接"
		}
		key := l.UserID
		if key == "" {
			key = l.Phone
		}
		if key == "" {
			key = l.WechatID
		}
		dupCount := dupCounts[key]
		if dupCount <= 1 {
			dupCount = 0
		}
		all = append(all, leadOut{
			SortTime: l.CreatedAt,
			Data: gin.H{
				"id":           l.ID,
				"type":         "lead",
				"userId":       l.UserID,
				"userNickname": userNickname,
				"userAvatar":   avatar,
				"phone":        l.Phone,
				"wechatId":     l.WechatID,
				"name":         l.Name,
				"source":       l.Source,
				"sourceLabel":  sourceLabel,
				"createdAt":    l.CreatedAt,
				"dupCount":     dupCount,
			},
		})
	}
	for _, s := range submits {
		u := userMap[s.UserID]
		avatar := ""
		userNickname := s.Nickname
		if u != nil {
			avatar = dashStr(u.Avatar)
			if dashStr(u.Nickname) != "" {
				userNickname = dashStr(u.Nickname)
			}
		}
		all = append(all, leadOut{
			SortTime: s.CreatedAt,
			Data: gin.H{
				"id":           s.ID,
				"type":         "submit",
				"userId":       s.UserID,
				"userNickname": userNickname,
				"userAvatar":   avatar,
				"matchType":    s.Action,
				"source":       s.Action,
				"sourceLabel":  ckbSourceMap[s.Action],
				"createdAt":    s.CreatedAt,
			},
		})
	}
	// 按时间倒序合并
	for i := 0; i < len(all); i++ {
		for j := i + 1; j < len(all); j++ {
			if all[j].SortTime.After(all[i].SortTime) {
				all[i], all[j] = all[j], all[i]
			}
		}
	}
	if len(all) > limit {
		all = all[:limit]
	}
	out := make([]gin.H, 0, len(all))
	for _, a := range all {
		out = append(out, a.Data)
	}
	c.JSON(http.StatusOK, gin.H{
		"success":      true,
		"leads":        out,
		"totalLeads":   totalLeads,
		"totalSubmits": totalSubmits,
		"withPhone":    withPhone,
		"total":        totalLeads + totalSubmits,
	})
}

func buildNewUsersOut(newUsers []model.User) []gin.H {
	out := make([]gin.H, 0, len(newUsers))
	for _, u := range newUsers {
		out = append(out, gin.H{
			"id":           u.ID,
			"nickname":     dashStr(u.Nickname),
			"phone":        dashStr(u.Phone),
			"referralCode": dashStr(u.ReferralCode),
			"createdAt":    u.CreatedAt,
		})
	}
	return out
}