package main

import (
	"fmt"
	"os"

	"gorm.io/driver/postgres"
	"gorm.io/gorm"

	"alterminal/internal/jwk"
)

func openDB() (*gorm.DB, error) {
	dsn := fmt.Sprintf(
		"host=%s port=%s user=%s password=%s dbname=%s sslmode=disable TimeZone=UTC",
		envOr("DB_HOST", "localhost"),
		envOr("DB_PORT", "5432"),
		envOr("DB_USER", "postgres"),
		envOr("DB_PASSWORD", "postgres"),
		envOr("DB_NAME", "alterminal"),
	)

	// TranslateError 讓唯一鍵違規轉為 gorm.ErrDuplicatedKey,create-account 等指令以此辨識重複。
	db, err := gorm.Open(postgres.Open(dsn), &gorm.Config{TranslateError: true})
	if err != nil {
		return nil, err
	}

	if err := db.AutoMigrate(&User{}, &Session{}, &jwk.SigningKey{}, &Application{}); err != nil {
		return nil, fmt.Errorf("auto migrate: %w", err)
	}
	return db, nil
}

func envOr(key, fallback string) string {
	if v := os.Getenv(key); v != "" {
		return v
	}
	return fallback
}