record.go

/*
Copyright © 2021 Etienne Parent <tricky@beon.ca>

Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License.
You may obtain a copy of the License at

    http://www.apache.org/licenses/LICENSE-2.0

Unless required by applicable law or agreed to in writing, software
distributed under the License is distributed on an "AS IS" BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
See the License for the specific language governing permissions and
limitations under the License.
*/
package cmd

import (
	"bufio"
	"context"
	"errors"
	"fmt"
	"io"
	"log"
	"os"
	"strings"

	"github.com/docker/docker/api/types"
	"github.com/docker/docker/api/types/container"
	"github.com/docker/docker/api/types/mount"
	"github.com/docker/docker/client"
	"github.com/docker/docker/pkg/stdcopy"
	"github.com/spf13/cobra"
	"github.com/spf13/viper"
)

// recordCmd represents the record command
var recordCmd = &cobra.Command{
	Use:   "record [path to project]",
	Short: "Record a video using good-bot.",
	Long: `This command uses good-bot's container image
to record a project.

If the provided argument is a script, this command will
run the setup command first, and then use record.

If the argument is already a directory created by the
setup command, this command will only use the record
command to create the recordings.`,
	Run: func(cmd *cobra.Command, args []string) {
		setConfigInteraction()
		dockerCheck()
		processedArg, err := processPath(args[0])
		if err != nil {
			log.Fatalf("Got error trying to process the agrument '%s'. Error was:\n%s", args[0], err)
		}
		credentials := copyCredentials()
		isDir, err := isDirectory(processedArg)
		if err != nil {
			log.Fatal(err)
		}
		if isDir {
			runRecordCommand(processedArg, credentials.ttsFile, credentials.passwords, &languageSettings{language, languageName})
			if !noRender {
				renderAllRecordings(processedArg)
				if !gifsOnly {
					renderVideo(processedArg)
				}
			}
		} else {
			// TODO: Fix this.
			// runSetupCommand(args[0], "/project")
			// recDir := askRecDir()
			// runRecordCommand(recDir, credentials.ttsFile, credentials.passwords)
			// if !noRender {
			// 	renderProject("Toto")
			// }
			fmt.Printf("Cannot create a video from %s.\n", processedArg)
			fmt.Println("Please make sure that you used the setup command first.")
			os.Exit(1)
		}
	},
	Args: func(cmd *cobra.Command, args []string) error {
		if len(args) < 1 {
			return errors.New("requires at least one argument")
		} else if len(args) > 1 {
			return errors.New("requires at most one argument")
		} else if !validatePath(args[0]) { // d
			return errors.New("not a valid path")
		} else {
			return nil
		}
	},
}

type credentials struct {
	passwords []string
	ttsFile   string
}

var (
	gifsOnly     bool
	noRender     bool
	language     string
	languageName string
)

type languageSettings struct {
	lang     string
	langName string
}

func init() {

	rootCmd.AddCommand(recordCmd)

	// Here you will define your flags and configuration settings.

	// Cobra supports Persistent Flags which will work for this command
	// and all subcommands, e.g.:
	// recordCmd.PersistentFlags().String("foo", "", "A help for foo")

	// Cobra supports local flags which will only run when this command
	// is called directly, e.g.:
	// recordCmd.Flags().BoolP("toggle", "t", false, "Help message for toggle")
	recordCmd.Flags().BoolVar(&gifsOnly, "gifs-only", false, "Only produce gifs. No mp4 files will be created.")
	recordCmd.Flags().BoolVar(&noRender, "no-render", false, `If not rendering, Good-Bot only outputs asciicasts and 
audio recordings. No gifs or mp4 files are produced.`)
	recordCmd.Flags().StringVarP(&language, "language", "l", "en-US", "Which language code to use for the narration.")
	recordCmd.Flags().StringVarP(&languageName, "language-name", "n", "en-US-Standard-C", "Which language name to use for the narration.")
}

// runRecordCommand uses Good Bot's record command to record a project.
//
// The record command uses the directory created by setup to create Asciinema
// recordings and mp3 audio from the TTS engine.
//
// This function takes care of setting environment variables in the container.
// It also creates the appropriate mount on the host computer to read and
// write on the project directory. The directory where the TTS credentials
// file is saved is  also mounted to give Good Bot access to the credentials.
//
// runRecordCommand also sets language settings by providing the required
// flags to the container's command-line interface.
func runRecordCommand(hostPath string, ttsFile string, envVars []string, settings *languageSettings) {
	// Used later for i/o between container and shell
	isRead, err := isReadStatement(hostPath)
	var containerTtsPath string
	var credentialsEnv string
	var resp container.ContainerCreateCreatedBody

	inout := make(chan []byte)

	ctx := context.Background()
	cli, err := client.NewClientWithOpts(client.FromEnv, client.WithAPIVersionNegotiation())
	if err != nil {
		panic(err)
	}


	if !imageExists("trickytroll/good-bot:latest", ctx, cli) {
		reader, err := cli.ImagePull(ctx, "trickytroll/good-bot:latest", types.ImagePullOptions{})
		if err != nil {
			panic(err)
		}
		io.Copy(os.Stdout, reader)
	}

	stats, err := os.Stat(hostPath)
	if err != nil {
		panic(err)
	}

	projectName := stats.Name()

	containerProjectPath := "/project" + "/" + projectName

	if err != nil {
		log.Fatal(err)
	}

	if isRead && len(ttsFile) < 1 {

		//////////////////////////////////////////////////////////////////
		// The user wants audio but does not have a credentials file    //
		//////////////////////////////////////////////////////////////////

		fmt.Println("You need a TTS credentials file to use 'read' statements in your script.")
		// TODO: add link to documentation here:
		fmt.Println("For more information on the credentials file, please refer to the documentation.")
		os.Exit(1)

	} else if isRead && len(ttsFile) > 1 { // There is a tts file and something to read.

		///////////////////////
		// Run with audio	 //
		///////////////////////

		ttyFileStats, err := os.Stat(ttsFile)
		if err != nil {
			panic(err)
		}
		ttsFileName := ttyFileStats.Name()

		containerTtsPath = "/credentials/" + ttsFileName
		credentialsEnv = fmt.Sprintf("GOOGLE_APPLICATION_CREDENTIALS=%s", containerTtsPath)
		envVars = append(envVars, credentialsEnv)

		resp, err = cli.ContainerCreate(ctx, &container.Config{
			AttachStdin:  true,
			AttachStdout: true,
			AttachStderr: true,
			Tty:          true,
			OpenStdin:    true,
			Env:          envVars,
			Cmd:          []string{"record", containerProjectPath, "-l", settings.lang, "-n", settings.langName},
			Image:        "trickytroll/good-bot:latest",
			Volumes:      map[string]struct{}{},
		}, &container.HostConfig{
			Mounts: []mount.Mount{
				{
					Type:   mount.TypeBind,
					Source: getDir(hostPath),
					Target: "/project",
				},
				{
					Type:   mount.TypeBind,
					Source: getDir(ttsFile),
					Target: "/credentials",
				},
			},
		}, nil, nil, "")
		if err != nil {
			panic(err)
		}

	} else {

		//////////////////////////
		// Run without audio    //
		//////////////////////////

		resp, err = cli.ContainerCreate(ctx, &container.Config{
			AttachStdin:  true,
			AttachStdout: true,
			AttachStderr: true,
			Tty:          true,
			OpenStdin:    true,
			// No need for language settings since there is no audio.
			Cmd:          []string{"record", containerProjectPath},
			Image:        "trickytroll/good-bot:latest",
			Volumes:      map[string]struct{}{},
		}, &container.HostConfig{
			Mounts: []mount.Mount{
				{
					Type:   mount.TypeBind,
					Source: getDir(hostPath),
					Target: "/project",
				},
				{
					Type:   mount.TypeBind,
					Source: getDir(ttsFile),
					Target: "/credentials",
				},
			},
		}, nil, nil, "")
		if err != nil {
			panic(err)
		}
	}


	if err := cli.ContainerStart(ctx, resp.ID, types.ContainerStartOptions{}); err != nil {
		panic(err)
	}
	// Need to attach since the user will be interacting with the container
	waiter, err := cli.ContainerAttach(ctx, resp.ID, types.ContainerAttachOptions{
		Stderr: true,
		Stdout: true,
		Stdin:  true,
		Stream: true,
	})

	// Starting a goroutine for copying. Copies container output to stdout.
	go io.Copy(os.Stdout, waiter.Reader)
	go io.Copy(os.Stderr, waiter.Reader)

	if err != nil {
		panic(err)
	}

	go func() { // In a goroutine
		scanner := bufio.NewScanner(os.Stdin)
		for scanner.Scan() { // Write terminal input to inout channel
			inout <- []byte(scanner.Text())
		}
	}()

	go func(w io.WriteCloser) { // In another goroutine
		for {
			data, ok := <-inout // Get terminal input from channel
			if !ok {
				fmt.Println("!ok")
				w.Close()
				return
			}

			w.Write(append(data, '\n')) // Write input to `w`. `w` is a Conn interface.
			// See https://pkg.go.dev/net#Conn
		}
	}(waiter.Conn)

	statusCh, errCh := cli.ContainerWait(ctx, resp.ID, container.WaitConditionNotRunning)
	select {
	case err := <-errCh:
		if err != nil {
			panic(err)
		}
	case <-statusCh:
	}

	out, err := cli.ContainerLogs(ctx, resp.ID, types.ContainerLogsOptions{ShowStdout: true})
	if err != nil {
		panic(err)
	}

	stdcopy.StdCopy(os.Stdout, os.Stderr, out)
}

// isDirectory checks whether or not a path is a directory. It uses
// os.Stat to get information on the provided path, and then uses
// IsDir on the information provided.
func isDirectory(path string) (bool, error) {
	// path should be valid since it's been checked by validatePath()
	info, err := os.Stat(path)
	if err != nil {
		// If path is not valid, it means that there is a missing
		// validatePath() somewhere.
		return false, err
	}
	return info.IsDir(), nil
}

// parsePasswords reads a password file and stores its values in an array.
// Using the provided passwordsPath, it reads the file and trims newline
// characters. The processed lines are then returned.
func parsePasswords(passwordsPath string) ([]string, error) {
	file, err := os.Open(passwordsPath)
	if err != nil {
		return nil, err
	}
	defer file.Close()

	var lines []string
	scanner := bufio.NewScanner(file)
	for scanner.Scan() {
		lines = append(lines, strings.Trim(scanner.Text(), "\n"))
	}
	return lines, scanner.Err()
}

// copyCredentials unpacks the TTS credentials and passwords from
// Viper strings into a credentials structure. It returns an instance
// of credentials filled with values from Viper.
func copyCredentials() *credentials {

	ttsCredentials := viper.GetString("ttsCredentials")
	passwordsEnv := viper.GetString("passwordsEnv")

	allPasswords, _ := parsePasswords(passwordsEnv)

	return &credentials{allPasswords, ttsCredentials}
}