package orm

import (
	"fmt"
	"log/slog"
	"os"

	"github.com/pkg/errors"
	"gorm.io/driver/postgres"
	"gorm.io/gorm"
	"gorm.io/gorm/logger"
)

var DB *gorm.DB

func Init() {
	Host := os.Getenv("DB_HOST")
	Port := os.Getenv("DB_PORT")
	Database := os.Getenv("DB_DATABASE")
	Username := os.Getenv("DB_USERNAME")
	Password := os.Getenv("DB_PASSWORD")
	Timezone := os.Getenv("DB_TIMEZONE")

	dsn := fmt.Sprintf(
		"host=%s port=%s user=%s password=%s dbname=%s sslmode=disable TimeZone=%s",
		Host, Port, Username, Password, Database, Timezone,
	)

	db, err := gorm.Open(postgres.Open(dsn), &gorm.Config{
		Logger: logger.Default,
	})
	if err != nil {
		panic(err)
	}

	DB = db
}

func MaySingle[T any](results []T) (*T, error) {
	rsLen := len(results)
	if rsLen == 0 {
		return nil, errors.New("记录为空")
	}
	if rsLen > 1 {
		slog.Warn("记录不唯一", "ids")
	}
	return &results[0], nil
}