package main

import (
	"fmt"
	"os"
	"os/signal"
	"path"
	"strconv"

	"github.com/docker/machine/cli"
	"github.com/docker/machine/commands"
	"github.com/docker/machine/commands/mcndirs"
	"github.com/docker/machine/libmachine/log"
	"github.com/docker/machine/libmachine/mcnutils"
	"github.com/docker/machine/libmachine/ssh"
	"github.com/docker/machine/version"
)

var AppHelpTemplate = `Usage: {{.Name}} {{if .Flags}}[OPTIONS] {{end}}COMMAND [arg...]

{{.Usage}}

Version: {{.Version}}{{if or .Author .Email}}

Author:{{if .Author}}
  {{.Author}}{{if .Email}} - <{{.Email}}>{{end}}{{else}}
  {{.Email}}{{end}}{{end}}
{{if .Flags}}
Options:
  {{range .Flags}}{{.}}
  {{end}}{{end}}
Commands:
  {{range .Commands}}{{.Name}}{{with .ShortName}}, {{.}}{{end}}{{ "\t" }}{{.Usage}}
  {{end}}
Run '{{.Name}} COMMAND --help' for more information on a command.
`

var CommandHelpTemplate = `Usage: docker-machine {{.Name}}{{if .Flags}} [OPTIONS]{{end}} [arg...]

{{.Usage}}{{if .Description}}

Description:
   {{.Description}}{{end}}{{if .Flags}}

Options:
   {{range .Flags}}
   {{.}}{{end}}{{ end }}
`

func setDebugOutputLevel() {
	// TODO: I'm not really a fan of this method and really would rather
	// use -v / --verbose TBQH
	for _, f := range os.Args {
		if f == "-D" || f == "--debug" || f == "-debug" {
			log.IsDebug = true
		}
	}

	debugEnv := os.Getenv("MACHINE_DEBUG")
	if debugEnv != "" {
		showDebug, err := strconv.ParseBool(debugEnv)
		if err != nil {
			fmt.Fprintf(os.Stderr, "Error parsing boolean value from MACHINE_DEBUG: %s\n", err)
			os.Exit(1)
		}
		log.IsDebug = showDebug
	}
}

func main() {
	setDebugOutputLevel()
	cli.AppHelpTemplate = AppHelpTemplate
	cli.CommandHelpTemplate = CommandHelpTemplate
	app := cli.NewApp()
	app.Name = path.Base(os.Args[0])
	app.Author = "Docker Machine Contributors"
	app.Email = "https://github.com/docker/machine"
	app.Before = func(c *cli.Context) error {
		// TODO: Need better handling of config, everything is too
		// complected together right now.
		if c.GlobalBool("native-ssh") {
			ssh.SetDefaultClient(ssh.Native)
		}
		mcnutils.GithubApiToken = c.GlobalString("github-api-token")
		mcndirs.BaseDir = c.GlobalString("storage-path")
		return nil
	}

	app.Commands = commands.Commands
	app.CommandNotFound = cmdNotFound
	app.Usage = "Create and manage machines running Docker."
	app.Version = version.Version + " (" + version.GitCommit + ")"

	log.Debug("Docker Machine Version: ", app.Version)

	app.Flags = []cli.Flag{
		cli.BoolFlag{
			Name:  "debug, D",
			Usage: "Enable debug mode",
		},
		cli.StringFlag{
			EnvVar: "MACHINE_STORAGE_PATH",
			Name:   "s, storage-path",
			Value:  mcndirs.GetBaseDir(),
			Usage:  "Configures storage path",
		},
		cli.StringFlag{
			EnvVar: "MACHINE_TLS_CA_CERT",
			Name:   "tls-ca-cert",
			Usage:  "CA to verify remotes against",
			Value:  "",
		},
		cli.StringFlag{
			EnvVar: "MACHINE_TLS_CA_KEY",
			Name:   "tls-ca-key",
			Usage:  "Private key to generate certificates",
			Value:  "",
		},
		cli.StringFlag{
			EnvVar: "MACHINE_TLS_CLIENT_CERT",
			Name:   "tls-client-cert",
			Usage:  "Client cert to use for TLS",
			Value:  "",
		},
		cli.StringFlag{
			EnvVar: "MACHINE_TLS_CLIENT_KEY",
			Name:   "tls-client-key",
			Usage:  "Private key used in client TLS auth",
			Value:  "",
		},
		cli.StringFlag{
			EnvVar: "MACHINE_GITHUB_API_TOKEN",
			Name:   "github-api-token",
			Usage:  "Token to use for requests to the Github API",
			Value:  "",
		},
		cli.BoolFlag{
			EnvVar: "MACHINE_NATIVE_SSH",
			Name:   "native-ssh",
			Usage:  "Use the native (Go-based) SSH implementation.",
		},
	}

	go commands.DeferClosePluginServers()

	// Cleanup to run in case the user sends an interrupt (CTRL+C) to the
	// Machine program.  Ensure that we do not leave dangling OS processes.
	signalCh := make(chan os.Signal, 1)
	signal.Notify(signalCh, os.Interrupt)

	// Atypical exit condition -- write to the cleanup done channel after
	// ensuring that we have closed all exec-ed plugin servers.
	go func() {
		for range signalCh {
			log.Info("\nReceieved an interrupt, performing cleanup work...")
			close(commands.RpcClientDriversCh)
			<-commands.RpcDriversClosedCh
			os.Exit(1)
		}
	}()

	// TODO: Close plugin servers in case of client panic.
	if err := app.Run(os.Args); err != nil {
		log.Error(err)
	}

	close(commands.RpcClientDriversCh)
	<-commands.RpcDriversClosedCh
}

func cmdNotFound(c *cli.Context, command string) {
	log.Fatalf(
		"%s: '%s' is not a %s command. See '%s --help'.",
		c.App.Name,
		command,
		c.App.Name,
		os.Args[0],
	)
}
