package service

import (
	"time"

	"affiliate_dash/internal/model"
	"affiliate_dash/internal/pkg/timeutil"

	"gorm.io/gorm"
)

type DashboardStats struct {
	Scope                     string `json:"scope"`
	CatalogProductCount       int64  `json:"catalog_product_count"`
	ProductCount              int64  `json:"product_count"`
	ActiveProductCount        int64  `json:"active_product_count"`
	MerchantCount             int64  `json:"merchant_count"`
	ActiveMerchantCount       int64  `json:"active_merchant_count"`
	UserCount                 int64  `json:"user_count"`
	OrderCount                int64  `json:"order_count"`
	TodayOrderCount           int64  `json:"today_order_count"`
	TotalSales                int64  `json:"total_sales"`
	TodaySales                int64  `json:"today_sales"`
	TotalFees                 int64  `json:"total_fees"`
	TodayFees                 int64  `json:"today_fees"`
	PaidOrderCount            int64  `json:"paid_order_count"`
	DeliveringOrderCount      int64  `json:"delivering_order_count"`
	DeliveredOrderCount       int64  `json:"delivered_order_count"`
	ShipFailedOrderCount      int64  `json:"ship_failed_order_count"`
	CancelledOrderCount       int64  `json:"cancelled_order_count"`
	WalletAvailableBalance    int64  `json:"wallet_available_balance"`
	WalletFrozenBalance       int64  `json:"wallet_frozen_balance"`
	APIClientCount            int64  `json:"api_client_count"`
	ActiveAPIClientCount      int64  `json:"active_api_client_count"`
	CallbackSubscriptionCount int64  `json:"callback_subscription_count"`
	PendingCallbackCount      int64  `json:"pending_callback_count"`
	FailedCallbackCount       int64  `json:"failed_callback_count"`
}

type dashboardStatusCount struct {
	Status string
	Count  int64
}

// Dashboard 按角色汇总运营指标：平台管理员看全平台，商户账号看当前商户。
func (s *FulfillmentService) Dashboard(merchantID uint, isPlatformAdmin bool) (*DashboardStats, error) {
	stats := &DashboardStats{Scope: "merchant"}
	if isPlatformAdmin {
		stats.Scope = "platform"
	}
	todayStart := timeutil.StartOfDay(time.Now())

	productScope := func() *gorm.DB {
		tx := s.db.Model(&model.MerchantProduct{})
		if !isPlatformAdmin {
			tx = tx.Where("merchant_id = ?", merchantID)
		}
		return tx
	}
	orderScope := func() *gorm.DB {
		tx := s.db.Model(&model.FulfillmentOrder{})
		if !isPlatformAdmin {
			tx = tx.Where("merchant_id = ?", merchantID)
		}
		return tx
	}
	walletScope := func() *gorm.DB {
		tx := s.db.Model(&model.WalletAccount{})
		if !isPlatformAdmin {
			tx = tx.Where("merchant_id = ?", merchantID)
		}
		return tx
	}
	apiClientScope := func() *gorm.DB {
		tx := s.db.Model(&model.APIClient{})
		if !isPlatformAdmin {
			tx = tx.Where("merchant_id = ?", merchantID)
		}
		return tx
	}
	callbackScope := func() *gorm.DB {
		tx := s.db.Model(&model.CallbackSubscription{})
		if !isPlatformAdmin {
			tx = tx.Where("merchant_id = ?", merchantID)
		}
		return tx
	}
	callbackDeliveryScope := func() *gorm.DB {
		tx := s.db.Model(&model.CallbackDelivery{})
		if !isPlatformAdmin {
			tx = tx.Where("merchant_id = ?", merchantID)
		}
		return tx
	}

	if err := s.db.Model(&model.Product{}).Count(&stats.CatalogProductCount).Error; err != nil {
		return nil, err
	}
	if err := productScope().Count(&stats.ProductCount).Error; err != nil {
		return nil, err
	}
	if err := productScope().Where("status = ?", model.ProductStatusActive).Count(&stats.ActiveProductCount).Error; err != nil {
		return nil, err
	}
	if isPlatformAdmin {
		if err := s.db.Model(&model.Merchant{}).Count(&stats.MerchantCount).Error; err != nil {
			return nil, err
		}
		if err := s.db.Model(&model.Merchant{}).Where("status = ?", model.MerchantStatusActive).Count(&stats.ActiveMerchantCount).Error; err != nil {
			return nil, err
		}
		if err := s.db.Model(&model.User{}).Count(&stats.UserCount).Error; err != nil {
			return nil, err
		}
	} else {
		if err := s.db.Model(&model.Merchant{}).Where("id = ?", merchantID).Count(&stats.MerchantCount).Error; err != nil {
			return nil, err
		}
		if err := s.db.Model(&model.Merchant{}).Where("id = ? AND status = ?", merchantID, model.MerchantStatusActive).Count(&stats.ActiveMerchantCount).Error; err != nil {
			return nil, err
		}
		if err := s.db.Model(&model.User{}).
			Joins("JOIN merchant_members ON merchant_members.user_id = users.id").
			Where("merchant_members.merchant_id = ?", merchantID).
			Count(&stats.UserCount).Error; err != nil {
			return nil, err
		}
		stats.CatalogProductCount = stats.ProductCount
	}
	if err := orderScope().Count(&stats.OrderCount).Error; err != nil {
		return nil, err
	}
	if err := orderScope().Where("created_at >= ?", todayStart).Count(&stats.TodayOrderCount).Error; err != nil {
		return nil, err
	}
	if err := orderScope().Where("order_status <> ?", model.OrderStatusCancelled).
		Select("COALESCE(SUM(amount),0)").Scan(&stats.TotalSales).Error; err != nil {
		return nil, err
	}
	if err := orderScope().Where("order_status <> ?", model.OrderStatusCancelled).
		Where("created_at >= ?", todayStart).
		Select("COALESCE(SUM(amount),0)").Scan(&stats.TodaySales).Error; err != nil {
		return nil, err
	}
	if err := orderScope().Where("order_status <> ?", model.OrderStatusCancelled).
		Select("COALESCE(SUM(service_fee_amount),0)").Scan(&stats.TotalFees).Error; err != nil {
		return nil, err
	}
	if err := orderScope().Where("order_status <> ?", model.OrderStatusCancelled).
		Where("created_at >= ?", todayStart).
		Select("COALESCE(SUM(service_fee_amount),0)").Scan(&stats.TodayFees).Error; err != nil {
		return nil, err
	}
	var orderStatusCounts []dashboardStatusCount
	if err := orderScope().Select("order_status AS status, COUNT(*) AS count").
		Group("order_status").Scan(&orderStatusCounts).Error; err != nil {
		return nil, err
	}
	for _, item := range orderStatusCounts {
		switch item.Status {
		case model.OrderStatusPaid:
			stats.PaidOrderCount = item.Count
		case model.OrderStatusDelivering:
			stats.DeliveringOrderCount = item.Count
		case model.OrderStatusDelivered:
			stats.DeliveredOrderCount = item.Count
		case model.OrderStatusShipFailed:
			stats.ShipFailedOrderCount = item.Count
		case model.OrderStatusCancelled:
			stats.CancelledOrderCount = item.Count
		}
	}
	if err := walletScope().Select("COALESCE(SUM(available_balance),0)").Scan(&stats.WalletAvailableBalance).Error; err != nil {
		return nil, err
	}
	if err := walletScope().Select("COALESCE(SUM(frozen_balance),0)").Scan(&stats.WalletFrozenBalance).Error; err != nil {
		return nil, err
	}
	if err := apiClientScope().Count(&stats.APIClientCount).Error; err != nil {
		return nil, err
	}
	if err := apiClientScope().Where("status = ?", model.APIClientStatusActive).Count(&stats.ActiveAPIClientCount).Error; err != nil {
		return nil, err
	}
	if err := callbackScope().Count(&stats.CallbackSubscriptionCount).Error; err != nil {
		return nil, err
	}
	if err := callbackDeliveryScope().Where("status = ?", model.CallbackDeliveryPending).Count(&stats.PendingCallbackCount).Error; err != nil {
		return nil, err
	}
	if err := callbackDeliveryScope().Where("status = ?", model.CallbackDeliveryFailed).Count(&stats.FailedCallbackCount).Error; err != nil {
		return nil, err
	}
	return stats, nil
}