package controllers

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

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

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

type FeeSummaryData struct {
	TotalTransactions int64 `json:"total_transactions"`
	TotalRevenue      int   `json:"total_revenue"`
	TotalFee          int   `json:"total_fee"`
	TotalCash         int   `json:"total_cash"`
	TotalMidtrans     int   `json:"total_midtrans"`
	FeeCash           int   `json:"fee_cash"`
	FeeMidtrans       int   `json:"fee_midtrans"`
}

type CompanyFeeRow struct {
	CompanyID         uint    `json:"company_id"`
	CompanyName       string  `json:"company_name"`
	FeePercentage     float64 `json:"fee_percentage"`
	TotalTransactions int64   `json:"total_transactions"`
	TotalRevenue      int     `json:"total_revenue"`
	TotalFee          int     `json:"total_fee"`
	TotalCash         int     `json:"total_cash"`
	TotalMidtrans     int     `json:"total_midtrans"`
}

type BranchFeeRow struct {
	CompanyID         uint    `json:"company_id"`
	CompanyName       string  `json:"company_name"`
	BranchID          *uint   `json:"branch_id"`
	BranchName        string  `json:"branch_name"`
	TotalTransactions int64   `json:"total_transactions"`
	TotalRevenue      int     `json:"total_revenue"`
	TotalFee          int     `json:"total_fee"`
	TotalCash         int     `json:"total_cash"`
	TotalMidtrans     int     `json:"total_midtrans"`
}

type DailyFeeRow struct {
	Day               time.Time `json:"day"`
	CompanyID         uint      `json:"company_id"`
	CompanyName       string    `json:"company_name"`
	FeePercentage     float64   `json:"fee_percentage"`
	TotalTransactions int64     `json:"total_transactions"`
	TotalRevenue      int       `json:"total_revenue"`
	TotalFee          int       `json:"total_fee"`
}

func GetFeeReport(c *gin.Context) {
	dateFrom := c.Query("date_from")
	dateTo := c.Query("date_to")
	companyIDStr := c.Query("company_id")

	today := time.Now()
	var dFrom, dTo time.Time
	var err error

	if dateFrom != "" {
		dFrom, err = time.Parse("2006-01-02", dateFrom)
		if err != nil {
			c.JSON(http.StatusBadRequest, gin.H{"detail": "Format date_from salah, gunakan YYYY-MM-DD"})
			return
		}
	} else {
		// Default 30 hari lalu
		dFrom = today.AddDate(0, 0, -29)
	}

	if dateTo != "" {
		dTo, err = time.Parse("2006-01-02", dateTo)
		if err != nil {
			c.JSON(http.StatusBadRequest, gin.H{"detail": "Format date_to salah, gunakan YYYY-MM-DD"})
			return
		}
	} else {
		dTo = today
	}

	loc, _ := time.LoadLocation("Asia/Jakarta")
	if loc == nil {
		loc = time.Local
	}
	startDt := time.Date(dFrom.Year(), dFrom.Month(), dFrom.Day(), 0, 0, 0, 0, loc)
	endDt := time.Date(dTo.Year(), dTo.Month(), dTo.Day(), 23, 59, 59, 0, loc)

	// Helper local untuk membikin query fresh guna menghindari GORM method chaining state sharing bug (table name specified more than once)
	getFreshFeeQuery := func() *gorm.DB {
		q := config.DB.Table("orders").
			Where("orders.payment_status = ? AND orders.created_at >= ? AND orders.created_at <= ?", "paid", startDt, endDt)
		if companyIDStr != "" {
			if cID, err := strconv.Atoi(companyIDStr); err == nil {
				q = q.Where("orders.company_id = ?", cID)
			}
		}
		return q
	}

	// 1. Summary keseluruhan
	var summary FeeSummaryData
	getFreshFeeQuery().Select(`
		count(orders.id) as total_transactions,
		coalesce(sum(orders.total_amount), 0) as total_revenue,
		coalesce(sum(orders.platform_fee), 0) as total_fee,
		coalesce(sum(case when orders.payment_method = 'cash' then orders.total_amount else 0 end), 0) as total_cash,
		coalesce(sum(case when orders.payment_method != 'cash' then orders.total_amount else 0 end), 0) as total_midtrans,
		coalesce(sum(case when orders.payment_method = 'cash' then orders.platform_fee else 0 end), 0) as fee_cash,
		coalesce(sum(case when orders.payment_method != 'cash' then orders.platform_fee else 0 end), 0) as fee_midtrans
	`).Scan(&summary)

	// 2. Summary per perusahaan
	var perCompany []CompanyFeeRow
	getFreshFeeQuery().Select(`
		orders.company_id,
		companies.name as company_name,
		companies.fee_percentage,
		count(orders.id) as total_transactions,
		coalesce(sum(orders.total_amount), 0) as total_revenue,
		coalesce(sum(orders.platform_fee), 0) as total_fee,
		coalesce(sum(case when orders.payment_method = 'cash' then orders.total_amount else 0 end), 0) as total_cash,
		coalesce(sum(case when orders.payment_method != 'cash' then orders.total_amount else 0 end), 0) as total_midtrans
	`).
		Joins("join companies on companies.id = orders.company_id").
		Group("orders.company_id, companies.name, companies.fee_percentage").
		Order("total_fee desc").
		Scan(&perCompany)

	// 3. Summary per cabang
	var perBranch []BranchFeeRow
	getFreshFeeQuery().Select(`
		orders.company_id,
		companies.name as company_name,
		orders.branch_id,
		coalesce(branches.name, 'Tanpa Cabang') as branch_name,
		count(orders.id) as total_transactions,
		coalesce(sum(orders.total_amount), 0) as total_revenue,
		coalesce(sum(orders.platform_fee), 0) as total_fee,
		coalesce(sum(case when orders.payment_method = 'cash' then orders.total_amount else 0 end), 0) as total_cash,
		coalesce(sum(case when orders.payment_method != 'cash' then orders.total_amount else 0 end), 0) as total_midtrans
	`).
		Joins("join companies on companies.id = orders.company_id").
		Joins("left join branches on branches.id = orders.branch_id").
		Group("orders.company_id, companies.name, orders.branch_id, branches.name").
		Order("orders.company_id, total_revenue desc").
		Scan(&perBranch)

	// 4. Daily breakdown
	var dailyBreakdown []DailyFeeRow
	getFreshFeeQuery().Select(`
		DATE(orders.created_at) as day,
		orders.company_id,
		companies.name as company_name,
		companies.fee_percentage,
		count(orders.id) as total_transactions,
		coalesce(sum(orders.total_amount), 0) as total_revenue,
		coalesce(sum(orders.platform_fee), 0) as total_fee
	`).
		Joins("join companies on companies.id = orders.company_id").
		Group("DATE(orders.created_at), orders.company_id, companies.name, companies.fee_percentage").
		Order("day desc").
		Scan(&dailyBreakdown)

	// Buat daily_breakdown response yang clean format tanggalnya
	type DailyBreakdownResp struct {
		Date              string  `json:"date"`
		CompanyID         uint    `json:"company_id"`
		CompanyName       string  `json:"company_name"`
		FeePercentage     float64 `json:"fee_percentage"`
		TotalTransactions int64   `json:"total_transactions"`
		TotalRevenue      int     `json:"total_revenue"`
		TotalFee          int     `json:"total_fee"`
	}

	var dailyResp []DailyBreakdownResp
	for _, row := range dailyBreakdown {
		dailyResp = append(dailyResp, DailyBreakdownResp{
			Date:              row.Day.Format("2006-01-02"),
			CompanyID:         row.CompanyID,
			CompanyName:       row.CompanyName,
			FeePercentage:     row.FeePercentage,
			TotalTransactions: row.TotalTransactions,
			TotalRevenue:      row.TotalRevenue,
			TotalFee:          row.TotalFee,
		})
	}

	c.JSON(http.StatusOK, gin.H{
		"period": gin.H{
			"date_from": dFrom.Format("2006-01-02"),
			"date_to":   dTo.Format("2006-01-02"),
		},
		"summary":         summary,
		"per_company":     perCompany,
		"per_branch":      perBranch,
		"daily_breakdown": dailyResp,
	})
}

type CashFeeRule struct {
	MinAmount int `json:"min_amount"`
	MaxAmount int `json:"max_amount"`
	Fee       int `json:"fee"`
}

type QrisFeeRule struct {
	MinAmount     int     `json:"min_amount"`
	MaxAmount     int     `json:"max_amount"`
	FeePercentage float64 `json:"fee_percentage"`
	FeeFixed      int     `json:"fee_fixed"`
	FeeMin        int     `json:"fee_min"`
}

type UpdateFeeRequest struct {
	CashFeeRules       []CashFeeRule `json:"cash_fee_rules"`
	QrisFeeRules       []QrisFeeRule `json:"qris_fee_rules"`
	QrisFeePercentage  float64       `json:"qris_fee_percentage"`
	QrisFeeFixed       int           `json:"qris_fee_fixed"`
	QrisFeeMin         int           `json:"qris_fee_min"`
	QrisMinTransaction int           `json:"qris_min_transaction"`
	AllowQrisBelowMin  bool          `json:"allow_qris_below_min"`
}

func SetCompanyFee(c *gin.Context) {
	companyIDStr := c.Param("company_id")
	companyID, err := strconv.Atoi(companyIDStr)
	if err != nil {
		c.JSON(http.StatusBadRequest, gin.H{"detail": "ID perusahaan tidak valid"})
		return
	}

	var req UpdateFeeRequest
	if err := c.ShouldBindJSON(&req); err != nil {
		c.JSON(http.StatusBadRequest, gin.H{"detail": "Data konfigurasi fee tidak valid"})
		return
	}

	if req.QrisFeePercentage < 0 || req.QrisFeePercentage > 100 {
		c.JSON(http.StatusBadRequest, gin.H{"detail": "Fee percentage harus berupa angka antara 0 dan 100"})
		return
	}

	var company models.Company
	if err := config.DB.First(&company, companyID).Error; err != nil {
		c.JSON(http.StatusNotFound, gin.H{"detail": "Perusahaan tidak ditemukan"})
		return
	}

	rulesBytes, err := json.Marshal(req.CashFeeRules)
	if err != nil {
		c.JSON(http.StatusInternalServerError, gin.H{"detail": "Gagal memproses aturan fee tunai"})
		return
	}

	qrisRulesBytes, err := json.Marshal(req.QrisFeeRules)
	if err != nil {
		c.JSON(http.StatusInternalServerError, gin.H{"detail": "Gagal memproses aturan fee qris"})
		return
	}

	company.CashFeeRules = string(rulesBytes)
	company.QrisFeeRules = string(qrisRulesBytes)
	company.QrisFeePercentage = req.QrisFeePercentage
	company.QrisFeeFixed = req.QrisFeeFixed
	company.QrisFeeMin = req.QrisFeeMin
	company.QrisMinTransaction = req.QrisMinTransaction
	company.AllowQrisBelowMin = req.AllowQrisBelowMin

	// Keep backward compatibility if fee_percentage is still used somewhere
	company.FeePercentage = req.QrisFeePercentage

	if err := config.DB.Save(&company).Error; err != nil {
		c.JSON(http.StatusInternalServerError, gin.H{"detail": "Gagal menyimpan konfigurasi fee perusahaan"})
		return
	}

	c.JSON(http.StatusOK, gin.H{
		"message":      fmt.Sprintf("Konfigurasi fee perusahaan '%s' berhasil diperbarui", company.Name),
		"company_id":   company.ID,
		"company_name": company.Name,
	})
}