package database

import (
	"database/sql"
	"log"
	"os"
	"path"
	"time"

	"github.com/jinzhu/gorm"
	"github.com/robfig/cron/v3"
	"github.com/spf13/viper"

	// Dialects for gorm
	_ "github.com/jinzhu/gorm/dialects/postgres"
	_ "github.com/jinzhu/gorm/dialects/sqlite"
)

// Db is the open Database
var Db *gorm.DB

// URL defines the structure of a shortened URL
type URL struct {
	CreatedAt time.Time
	UpdatedAt time.Time

	Short sql.NullString `gorm:"primary_key;unique_index:short_url;not null"`
	Long  sql.NullString `gorm:"unique"`
	Hits  sql.NullInt64

	FileName   sql.NullString `gorm:"default:NULL"`
	FileSize   sql.NullInt64  `gorm:"default:NULL"`
	FileHash   sql.NullString `gorm:"default:NULL"`
	FileDelete *time.Time     `gorm:"default:NULL"`
}

// InitDb opens a database connection and runs the auto migration
func InitDb() {
	var err error
	Db, err = gorm.Open(viper.GetString("DBType"), viper.GetString("DBConnection"))
	if err != nil {
		log.Fatal("Could not open database:", err)
	}
	if os.Getenv("GIN_MODE") != "release" {
		Db.LogMode(true)
	}

	Db.AutoMigrate(&URL{})

	c := cron.New()
	c.AddFunc("@daily", deleteOldFiles)
}

func deleteOldFiles() {
	var URLs []URL
	Db.Find(&URLs, "file_delete < NOW()")
	for _, URL := range URLs {
		file := path.Join(viper.GetString("FileFolder"), URL.FileName.String)
		os.Remove(file)
		Db.Delete(&URL)
	}
}