package repository

import (
	"errors"
	"repo-pattern/app/repository/smartfilter"

	"gorm.io/gorm"
	"gorm.io/gorm/schema"
)

type ExistsMethod[T schema.Tabler] struct {
	DbConn *gorm.DB
}

func (m *ExistsMethod[T]) Init(dbConn *gorm.DB) {
	m.DbConn = dbConn
}

func (m ExistsMethod[T]) Exists(filter interface{}) (bool, error) {
	var (
		model T
	)

	query := m.DbConn.Model(model)

	query, err := smartfilter.ToQuery(model, filter, query)
	if err != nil {
		return false, err
	}

	result := query.Select("*").First(&model)

	exists := !errors.Is(result.Error, gorm.ErrRecordNotFound) && result.Error == nil
	return exists, nil
}