package repository

import (
	"context"
	"fmt"

	"apskel-pos-be/internal/entities"

	"gorm.io/gorm"
)

type CustomerPointsRepository interface {
	GetCustomerTotalPoints(ctx context.Context, customerID string) (int64, error)
	GetCustomerTotalTokens(ctx context.Context, customerID string) (int64, error)
	GetCustomerPointsHistory(ctx context.Context, customerID string, limit int) ([]entities.CustomerPoints, error)
	GetCustomerTokensHistory(ctx context.Context, customerID string, limit int) ([]entities.CustomerTokens, error)
}

type customerPointsRepository struct {
	db *gorm.DB
}

func NewCustomerPointsRepository(db *gorm.DB) CustomerPointsRepository {
	return &customerPointsRepository{
		db: db,
	}
}

func (r *customerPointsRepository) GetCustomerTotalPoints(ctx context.Context, customerID string) (int64, error) {
	var totalPoints int64

	err := r.db.WithContext(ctx).
		Model(&entities.CustomerPoints{}).
		Where("customer_id = ?", customerID).
		Select("COALESCE(SUM(balance), 0)").
		Scan(&totalPoints).Error

	if err != nil {
		return 0, fmt.Errorf("failed to get customer total points: %w", err)
	}

	return totalPoints, nil
}

func (r *customerPointsRepository) GetCustomerTotalTokens(ctx context.Context, customerID string) (int64, error) {
	var totalTokens int64

	err := r.db.WithContext(ctx).
		Model(&entities.CustomerTokens{}).
		Where("customer_id = ?", customerID).
		Select("COALESCE(SUM(balance), 0)").
		Scan(&totalTokens).Error

	if err != nil {
		return 0, fmt.Errorf("failed to get customer total tokens: %w", err)
	}

	return totalTokens, nil
}

func (r *customerPointsRepository) GetCustomerPointsHistory(ctx context.Context, customerID string, limit int) ([]entities.CustomerPoints, error) {
	var pointsHistory []entities.CustomerPoints

	query := r.db.WithContext(ctx).
		Where("customer_id = ?", customerID).
		Order("created_at DESC")

	if limit > 0 {
		query = query.Limit(limit)
	}

	err := query.Find(&pointsHistory).Error
	if err != nil {
		return nil, fmt.Errorf("failed to get customer points history: %w", err)
	}

	return pointsHistory, nil
}

func (r *customerPointsRepository) GetCustomerTokensHistory(ctx context.Context, customerID string, limit int) ([]entities.CustomerTokens, error) {
	var tokensHistory []entities.CustomerTokens

	query := r.db.WithContext(ctx).
		Where("customer_id = ?", customerID).
		Order("created_at DESC")

	if limit > 0 {
		query = query.Limit(limit)
	}

	err := query.Find(&tokensHistory).Error
	if err != nil {
		return nil, fmt.Errorf("failed to get customer tokens history: %w", err)
	}

	return tokensHistory, nil
}