package controllers

import (
	"fmt"
	"net/http"
	"strconv"
	"strings"
	"time"

	"service-warungpos-go/config"
	"service-warungpos-go/models"

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

type TopProductRow struct {
	ProductName   string `json:"product_name"`
	TotalQuantity int    `json:"total_quantity"`
	TotalRevenue  int    `json:"total_revenue"`
}

type SummaryTopProduct struct {
	Name         string `json:"name"`
	TotalSold    int    `json:"total_sold"`
	TotalRevenue int    `json:"total_revenue"`
}

type ReportOrderRow struct {
	OrderNumber    string    `json:"order_number"`
	TotalAmount    int       `json:"total_amount"`
	SubtotalAmount int       `json:"subtotal_amount"`
	PaymentMethod  string    `json:"payment_method"`
	CreatedAt      time.Time `json:"created_at"`
	Items          string    `json:"items"`
}

func getDayRange(targetDate time.Time) (time.Time, time.Time) {
	// Buat range awal dan akhir hari di timezone lokal/WIB (Asia/Jakarta)
	loc, _ := time.LoadLocation("Asia/Jakarta")
	if loc == nil {
		loc = time.Local
	}
	start := time.Date(targetDate.Year(), targetDate.Month(), targetDate.Day(), 0, 0, 0, 0, loc)
	end := start.Add(24 * time.Hour)
	return start, end
}

func fmtRupiah(amount int) string {
	// Helper formatting rupiah untuk internal log atau respons
	str := fmt.Sprintf("%d", amount)
	var result []string
	length := len(str)
	for i := length; i > 0; i -= 3 {
		start := i - 3
		if start < 0 {
			start = 0
		}
		result = append([]string{str[start:i]}, result...)
	}
	return "Rp " + strings.Join(result, ".")
}

// Helper strings.Join untuk formatting di atas

func DailyReport(c *gin.Context) {
	userVal, _ := c.Get("user")
	user := userVal.(*models.User)

	dateQuery := c.Query("date") // YYYY-MM-DD
	branchQuery := c.Query("branch_id")

	var targetDate time.Time
	var err error
	if dateQuery != "" {
		targetDate, err = time.Parse("2006-01-02", dateQuery)
		if err != nil {
			c.JSON(http.StatusBadRequest, gin.H{"detail": "Format tanggal salah, gunakan YYYY-MM-DD"})
			return
		}
	} else {
		// Default: Hari ini
		targetDate = time.Now()
	}

	startDt, endDt := getDayRange(targetDate)

	query := config.DB.Preload("Items.Product").
		Where("company_id = ? AND created_at >= ? AND created_at < ? AND payment_status = ?", *user.CompanyID, startDt, endDt, "paid")

	if branchQuery != "" {
		if bID, err := strconv.Atoi(branchQuery); err == nil {
			query = query.Where("branch_id = ?", bID)
		}
	}

	var orders []models.Order
	if err := query.Find(&orders).Error; err != nil {
		c.JSON(http.StatusInternalServerError, gin.H{"detail": "Gagal mengambil data laporan harian"})
		return
	}

	totalRevenue := 0
	totalCash := 0
	totalMidtrans := 0
	totalPlatformFee := 0

	var orderRows []ReportOrderRow
	for _, o := range orders {
		totalRevenue += o.TotalAmount
		if o.PaymentMethod == "cash" {
			totalCash += o.TotalAmount
		} else if o.PaymentMethod == "midtrans" || o.PaymentMethod == "tripay" {
			totalMidtrans += o.TotalAmount
		}
		totalPlatformFee += o.PlatformFee

		itemNames := []string{}
		for _, item := range o.Items {
			name := "Item"
			if item.Product != nil {
				name = item.Product.Name
			}
			itemNames = append(itemNames, fmt.Sprintf("%s (x%d)", name, item.Quantity))
		}
		
		itemsStr := strings.Join(itemNames, ", ")

		orderRows = append(orderRows, ReportOrderRow{
			OrderNumber:    o.OrderNumber,
			TotalAmount:    o.TotalAmount,
			SubtotalAmount: o.SubtotalAmount,
			PaymentMethod:  o.PaymentMethod,
			CreatedAt:      o.CreatedAt,
			Items:          itemsStr,
		})
	}

	// Query Top 5 produk terlaris hari ini
	var topProducts []TopProductRow
	topQuery := config.DB.Table("products").
		Select("products.name as product_name, sum(order_items.quantity) as total_quantity, sum(order_items.subtotal) as total_revenue").
		Joins("join order_items on products.id = order_items.product_id").
		Joins("join orders on order_items.order_id = orders.id").
		Where("orders.company_id = ? AND orders.payment_status = ? AND orders.created_at >= ? AND orders.created_at < ?", *user.CompanyID, "paid", startDt, endDt)

	if branchQuery != "" {
		if bID, err := strconv.Atoi(branchQuery); err == nil {
			topQuery = topQuery.Where("orders.branch_id = ?", bID)
		}
	}

	topQuery.Group("products.name").
		Order("total_quantity desc").
		Limit(5).
		Scan(&topProducts)

	c.JSON(http.StatusOK, gin.H{
		"date":               targetDate.Format("2006-01-02"),
		"total_transactions": len(orders),
		"total_revenue":      totalRevenue,
		"total_cash":         totalCash,
		"total_midtrans":     totalMidtrans,
		"total_platform_fee": totalPlatformFee,
		"top_products":       topProducts,
		"orders":             orderRows,
	})
}

func SummaryReport(c *gin.Context) {
	userVal, _ := c.Get("user")
	user := userVal.(*models.User)

	branchQuery := c.Query("branch_id")

	// 1. Total Semua Transaksi Sukses
	totalOrders := int64(0)
	totalRevenue := int64(0)

	totalQuery := config.DB.Model(&models.Order{}).
		Where("company_id = ? AND payment_status = ?", *user.CompanyID, "paid")

	if branchQuery != "" {
		if bID, err := strconv.Atoi(branchQuery); err == nil {
			totalQuery = totalQuery.Where("branch_id = ?", bID)
		}
	}

	totalQuery.Count(&totalOrders)
	totalQuery.Select("coalesce(sum(total_amount), 0)").Row().Scan(&totalRevenue)

	// 2. Total Produk Aktif yang Tersedia
	var totalProducts int64
	prodQuery := config.DB.Model(&models.Product{}).
		Where("company_id = ? AND is_active = ?", *user.CompanyID, true)

	if branchQuery != "" {
		if bID, err := strconv.Atoi(branchQuery); err == nil {
			// Subquery pengecualian produk tidak aktif di cabang ini
			subQuery := config.DB.Model(&models.BranchProduct{}).
				Select("product_id").
				Where("branch_id = ? AND is_available = ?", bID, false)
			prodQuery = prodQuery.Where("id NOT IN (?)", subQuery)
		}
	}
	prodQuery.Count(&totalProducts)

	// 3. Top 5 Produk Terlaris All-Time
	var topProducts []SummaryTopProduct
	topQuery := config.DB.Table("products").
		Select("products.name as name, sum(order_items.quantity) as total_sold, sum(order_items.subtotal) as total_revenue").
		Joins("join order_items on products.id = order_items.product_id").
		Joins("join orders on order_items.order_id = orders.id").
		Where("orders.company_id = ? AND orders.payment_status = ?", *user.CompanyID, "paid")

	if branchQuery != "" {
		if bID, err := strconv.Atoi(branchQuery); err == nil {
			topQuery = topQuery.Where("orders.branch_id = ?", bID)
		}
	}

	topQuery.Group("products.name").
		Order("total_sold desc").
		Limit(5).
		Scan(&topProducts)

	// 4. Laporan Hari Ini
	todayOrders := int64(0)
	todayRevenue := int64(0)

	startToday, endToday := getDayRange(time.Now())

	todayQuery := config.DB.Model(&models.Order{}).
		Where("company_id = ? AND payment_status = ? AND created_at >= ? AND created_at < ?", *user.CompanyID, "paid", startToday, endToday)

	if branchQuery != "" {
		if bID, err := strconv.Atoi(branchQuery); err == nil {
			todayQuery = todayQuery.Where("branch_id = ?", bID)
		}
	}

	todayQuery.Count(&todayOrders)
	todayQuery.Select("coalesce(sum(total_amount), 0)").Row().Scan(&todayRevenue)

	// 5. Laporan QRIS
	var qrisRevenue int64
	var qrisFee int64

	qrisQuery := config.DB.Model(&models.Order{}).
		Where("company_id = ? AND payment_status = ? AND payment_method != 'cash'", *user.CompanyID, "paid")

	if branchQuery != "" {
		if bID, err := strconv.Atoi(branchQuery); err == nil {
			qrisQuery = qrisQuery.Where("branch_id = ?", bID)
		}
	}

	qrisQuery.Select("coalesce(sum(total_amount), 0), coalesce(sum(platform_fee), 0)").Row().Scan(&qrisRevenue, &qrisFee)

	c.JSON(http.StatusOK, gin.H{
		"all_time": gin.H{
			"total_orders":  totalOrders,
			"total_revenue": totalRevenue,
		},
		"today": gin.H{
			"total_orders":  todayOrders,
			"total_revenue": todayRevenue,
		},
		"qris_report": gin.H{
			"total_transactions": qrisRevenue,
			"system_fee":         qrisFee,
			"net_amount":         qrisRevenue - qrisFee,
		},
		"total_products": totalProducts,
		"top_products":   topProducts,
	})
}