package main

import (
	"database/sql"
	"flag"
	"fmt"
	"log"
	"os"

	"github.com/pressly/goose"

	_ "github.com/pressly/goose/example/migrations-go"

	_ "github.com/go-sql-driver/mysql"
	_ "github.com/lib/pq"
	_ "github.com/mattn/go-sqlite3"
	_ "github.com/ziutek/mymysql/godrv"
)

var (
	flags = flag.NewFlagSet("goose", flag.ExitOnError)
	dir   = flags.String("dir", ".", "directory with migration files")
)

func main() {
	flags.Usage = usage
	flags.Parse(os.Args[1:])

	args := flags.Args()
	if len(args) != 3 {
		flags.Usage()
		return
	}

	if args[0] == "-h" || args[0] == "--help" {
		flags.Usage()
		return
	}

	driver, dbstring, command := args[0], args[1], args[2]

	switch driver {
	case "postgres", "mysql", "sqlite3":
		if err := goose.SetDialect(driver); err != nil {
			log.Fatal(err)
		}
	default:
		log.Fatalf("%q driver not supported\n", driver)
	}

	switch dbstring {
	case "":
		log.Fatalf("-dbstring=%q not supported\n", dbstring)
	default:
	}

	db, err := sql.Open(driver, dbstring)
	if err != nil {
		log.Fatalf("-dbstring=%q: %v\n", dbstring, err)
	}

	if err := goose.Run(command, db, *dir); err != nil {
		log.Fatalf("goose run: %v", err)
	}
}

func usage() {
	fmt.Print(usagePrefix)
	flags.PrintDefaults()
	fmt.Print(usageCommands)
}

var (
	usagePrefix = `Usage: goose [OPTIONS] DRIVER DBSTRING COMMAND

Examples:
    goose postgres "user=postgres dbname=postgres sslmode=disable" up
    goose mysql "user:password@/dbname" down
    goose sqlite3 ./foo.db status

Options:
`

	usageCommands = `
Commands:
    up         Migrate the DB to the most recent version available
    down       Roll back the version by 1
    redo       Re-run the latest migration
    status     Dump the migration status for the current DB
    dbversion  Print the current version of the database
`
)