package report

import (
	"context"

	"fmt"

	"github.com/SamuelTariku/FortuneBet-Backend/internal/domain"
	"go.uber.org/zap"
)

type CompanyIntervalRow struct {
	Period               string  `csv:"Period"`
	CompanyName          string  `csv:"CompanyName"`
	TotalBets            int64   `csv:"Total Bets"`
	TotalStake           float32 `csv:"Total Stake"`
	DeductedStake        float32 `csv:"Deducted Stake"`
	TotalCashOut         float32 `csv:"Total CashOut"`
	TotalCashBacks       float32 `csv:"Total CashBacks"`
	NumberOfUnsettled    int64   `csv:"Number Of Unsettled"`
	TotalUnsettledAmount float32 `csv:"Total Unsettled Amount"`
	TotalAdmins          int64   `csv:"Total Admins"`
	TotalManagers        int64   `csv:"Total Managers"`
	TotalCashiers        int64   `csv:"Total Cashiers"`
	TotalCustomers       int64   `csv:"Total Customers"`
	TotalApprovers       int64   `csv:"Total Approvers"`
	TotalBranches        int64   `csv:"Total Branches"`
}

func (s *Service) GenerateCompanyIntervalReport(ctx context.Context, request domain.ReportRequestDetail) (string, error) {
	
	// Only a super-admin is allowed to generate this type of report
	if request.RequesterRole.Valid && request.RequesterRole.Value != domain.RoleSuperAdmin {
		s.mongoLogger.Error("[GenerateCompanyIntervalReport] Unauthorized user report")
		return "", ErrUnauthorizedUserReport
	}
	
	if request.Metadata.Interval == nil {
		s.mongoLogger.Error("[GenerateCompanyIntervalReport] Metadata interval is empty")
		return "", domain.ErrInvalidInterval
	}

	interval, err := domain.ParseDateInterval(*request.Metadata.Interval)
	if err != nil {
		s.mongoLogger.Error("[GenerateCompanyIntervalReport] Failed to parse date interval",
			zap.String("interval", *request.Metadata.Interval),
			zap.Error(err),
		)
		return "", domain.ErrInvalidInterval
	}

	stats, err := s.statService.GetCompanyStatsByInterval(ctx, domain.CompanyStatFilter{
		Interval: domain.ValidDateInterval{
			Value: interval,
			Valid: true,
		},
	})
	if err != nil {
		s.mongoLogger.Error("[GenerateCompanyIntervalReport] Failed to fetch company stats",
			zap.String("interval", string(interval)),
			zap.Error(err),
		)
		return "", fmt.Errorf("fetching company stats: %w", err)
	}

	var rows [][]string
	var headers []string
	for _, stat := range stats {
		endDate, err := domain.GetEndDateFromInterval(interval, stat.IntervalStart)
		if err != nil {
			s.mongoLogger.Error("[GenerateCompanyIntervalReport] Failed to get end date from interval",
				zap.String("interval", string(interval)),
				zap.Error(err),
			)
			return "", fmt.Errorf("invalid interval end date: %w", err)
		}

		period := fmt.Sprintf("%s to %s",
			stat.IntervalStart.Format("2006-01-02"),
			endDate.Format("2006-01-02"),
		)

		r := CompanyIntervalRow{
			Period:               period,
			CompanyName:          stat.CompanyName,
			TotalBets:            stat.TotalBets,
			TotalStake:           stat.TotalStake.Float32(),
			DeductedStake:        stat.DeductedStake.Float32(),
			TotalCashOut:         stat.TotalCashOut.Float32(),
			TotalCashBacks:       stat.TotalCashBacks.Float32(),
			NumberOfUnsettled:    stat.NumberOfUnsettled,
			TotalUnsettledAmount: stat.TotalUnsettledAmount.Float32(),
			TotalAdmins:          stat.TotalAdmins,
			TotalManagers:        stat.TotalManagers,
			TotalCashiers:        stat.TotalCashiers,
			TotalCustomers:       stat.TotalCustomers,
			TotalApprovers:       stat.TotalApprovers,
			TotalBranches:        stat.TotalBranches,
		}

		if headers == nil {
			headers, _ = StructToCSVRow(r)
			rows = append(rows, headers)
		}

		_, row := StructToCSVRow(r)
		rows = append(rows, row)
	}

	return s.WriteCSV(rows, "company_interval")
}