refactor: major project restructure

cmd/download.go

@@ -1,231 +1,56 @@
 package cmd
 
 import (
+	"context"
+	"errors"
 	"fmt"
-	"os"
-	"path"
-	"strings"
-	"time"
 
-	"github.com/flytam/filenamify"
+	"github.com/mathismqn/godeez/internal/downloader"
-	"github.com/mathismqn/godeez/internal/config"
-	"github.com/mathismqn/godeez/internal/db"
-	"github.com/mathismqn/godeez/internal/deezer"
-	"github.com/mathismqn/godeez/internal/tags"
-	"github.com/mathismqn/godeez/internal/utils"
 	"github.com/spf13/cobra"
 )
 
-var (
+var opts downloader.Options
-	outputDir string
-	quality   string
-)
 
 var downloadCmd = &cobra.Command{
 	Use:   "download",
 	Short: "Download songs from Deezer",
 }
 
-type bpmResult struct {
-	tempo, key string
-	err        error
-}
-
 func init() {
 	RootCmd.AddCommand(downloadCmd)
-	downloadCmd.PersistentFlags().StringVarP(&outputDir, "output", "o", "", "output directory (default is $HOME/Music/GoDeez)")
+
-	downloadCmd.PersistentFlags().StringVarP(&quality, "quality", "q", "", "download quality [mp3_128, mp3_320, flac, best] (default is best)")
+	downloadCmd.PersistentFlags().StringVarP(&opts.OutputDir, "output", "o", "", "output directory (default is $HOME/Music/GoDeez)")
+	downloadCmd.PersistentFlags().StringVarP(&opts.Quality, "quality", "q", "", "download quality [mp3_128, mp3_320, flac, best] (default is best)")
+
+	downloadCmd.AddCommand(
+		newDownloadCmd("album"),
+		newDownloadCmd("playlist"),
+	)
 }
 
-func validateInput() {
+func newDownloadCmd(resourceType string) *cobra.Command {
-	if outputDir == "" {
+	cmd := &cobra.Command{
-		outputDir = appDir
+		Use:   fmt.Sprintf("%s [%s_id...]", resourceType, resourceType),
+		Short: fmt.Sprintf("Download songs from one or more %ss", resourceType),
+		Args:  cobra.MinimumNArgs(1),
+		PreRunE: func(cmd *cobra.Command, args []string) error {
+			return opts.Validate(appCtx.AppDir)
+		},
+		RunE: func(cmd *cobra.Command, args []string) error {
+			ctx := cmd.Context()
+			dl := downloader.New(appCtx, resourceType)
+
+			if err := dl.Run(ctx, opts, args); err != nil {
+				if errors.Is(err, context.Canceled) || errors.Is(err, context.DeadlineExceeded) {
+					return nil
+				}
+
+				return err
+			}
+
+			return nil
+		},
 	}
 
-	if quality == "" {
+	return cmd
-		quality = "best"
-	}
-
-	validQualities := map[string]bool{
-		"mp3_128": true,
-		"mp3_320": true,
-		"flac":    true,
-		"best":    true,
-	}
-	if !validQualities[quality] {
-		fmt.Fprintf(os.Stderr, "Error: invalid quality option: %s\n", quality)
-		os.Exit(1)
-	}
-}
-
-func downloadContent(contentType string, args []string) {
-	session, err := deezer.Authenticate(config.Cfg.ArlCookie)
-	if err != nil {
-		fmt.Fprintf(os.Stderr, "Error: could not authenticate: %v\n", err)
-		os.Exit(1)
-	}
-
-	nArgs := len(args)
-	separator := "--------------------------------------------------"
-
-	for i, id := range args {
-		fmt.Println(separator)
-		fmt.Printf("[%d/%d] Getting data for %s %s...", i+1, nArgs, contentType, id)
-
-		var resource deezer.Resource
-		var songs []*deezer.Song
-
-		switch contentType {
-		case "album":
-			album := &deezer.Album{}
-			if err := session.GetData(album, id); err != nil {
-				fmt.Printf("\r[%d/%d] Getting data for album %s... FAILED\n", i+1, nArgs, id)
-				fmt.Fprintf(os.Stderr, "Error: could not get album data: %v\n", err)
-
-				continue
-			}
-			resource = album
-			songs = album.GetSongs()
-		case "playlist":
-			playlist := &deezer.Playlist{}
-			if err := session.GetData(playlist, id); err != nil {
-				fmt.Printf("\r[%d/%d] Getting data for playlist %s... FAILED\n", i+1, nArgs, id)
-				fmt.Fprintf(os.Stderr, "Error: could not get playlist data: %v\n", err)
-
-				continue
-			}
-			if playlist.Results.Data.Status == 1 && playlist.Results.Data.CollabKey == "" {
-				fmt.Printf("\r[%d/%d] Getting data for playlist %s... FAILED\n", i+1, nArgs, id)
-				fmt.Fprintf(os.Stderr, "Error: playlist is private and no valid arl cookie was provided\n")
-
-				continue
-			}
-
-			resource = playlist
-			songs = playlist.GetSongs()
-		}
-
-		fmt.Printf("\r[%d/%d] Getting data for %s %s... DONE\n", i+1, nArgs, contentType, id)
-
-		output := resource.GetOutputPath(outputDir)
-		if err := utils.EnsureDir(output); err != nil {
-			fmt.Fprintf(os.Stderr, "Error: could not create output directory: %v\n", err)
-
-			continue
-		}
-
-		title := resource.GetTitle()
-		fmt.Printf("Starting download of %s: %s\n", contentType, title)
-
-		for _, song := range songs {
-			songTitle := song.Title
-			if song.Version != "" {
-				songTitle = fmt.Sprintf("%s %s", song.Title, song.Version)
-			}
-
-			media, err := song.GetMediaData(session.LicenseToken, quality)
-			if err != nil {
-				fmt.Printf("    Downloading %s... FAILED\n", songTitle)
-				fmt.Fprintf(os.Stderr, "Error: could not get media data: %v\n", err)
-				if err.Error() == "invalid license token" {
-					os.Exit(1)
-				}
-
-				continue
-			}
-
-			if len(media.Data) == 0 || len(media.Data[0].Media) == 0 || len(media.Data[0].Media[0].Sources) == 0 {
-				fmt.Printf("    Downloading %s... FAILED\n", songTitle)
-				fmt.Fprintf(os.Stderr, "Error: could not get media sources\n")
-
-				continue
-			}
-
-			url := media.Data[0].Media[0].Sources[0].URL
-			for _, source := range media.Data[0].Media[0].Sources {
-				if source.Provider == "ak" {
-					url = source.URL
-					break
-				}
-			}
-
-			ext := "mp3"
-			if media.Data[0].Media[0].Format == "FLAC" {
-				ext = "flac"
-			}
-			trackNumber := ""
-			if contentType == "album" {
-				trackNumber = song.TrackNumber + "."
-			}
-
-			fileName := fmt.Sprintf("%s %s - %s.%s", trackNumber, songTitle, strings.Join(song.Contributors.MainArtists, ", "), ext)
-			fileName, _ = filenamify.Filenamify(fileName, filenamify.Options{})
-			filePath := path.Join(output, fileName)
-
-			if existing, err := db.Get(song.ID); err == nil && existing.Quality == media.Data[0].Media[0].Format {
-				if utils.FileExists(existing.Path) {
-					fmt.Printf("    Skipping %s (already downloaded at %s)\n", songTitle, existing.Path)
-					continue
-				}
-				if existing.Hash != "" {
-					if foundPath, err := utils.FindFileByHash(appDir, existing.Hash); err == nil && foundPath != "" {
-						existing.Path = foundPath
-						_ = existing.Save()
-						fmt.Printf("    Recovered %s at %s, skipping download\n", songTitle, foundPath)
-
-						continue
-					}
-				}
-			}
-
-			fmt.Printf("    Downloading %s...", songTitle)
-
-			bpmCh := make(chan bpmResult, 1)
-			go func() {
-				t, k, e := song.GetTempoAndKey()
-				bpmCh <- bpmResult{tempo: t, key: k, err: e}
-			}()
-
-			err = media.Download(url, filePath, song.ID)
-			if err != nil {
-				fmt.Printf("\r    Downloading %s... FAILED\n", songTitle)
-				fmt.Fprintf(os.Stderr, "Error: could not download song: %v\n", err)
-				utils.DeleteFile(filePath)
-
-				continue
-			}
-			fmt.Printf("\r    Downloading %s... DONE\n", songTitle)
-
-			res := <-bpmCh
-			if res.err != nil {
-				fmt.Fprintf(os.Stderr, "Warning: could not get tempo/key for %s: %v\n", songTitle, res.err)
-			} else {
-				fmt.Printf("        Tempo: %s\n", res.tempo)
-				fmt.Printf("        Key: %s\n", res.key)
-			}
-
-			if err := tags.AddTags(resource, song, filePath, res.tempo, res.key); err != nil {
-				fmt.Fprintf(os.Stderr, "Warning: could not add tags to song: %v\n", err)
-			}
-
-			hash, err := utils.GetFileHash(filePath)
-			if err != nil {
-				fmt.Fprintf(os.Stderr, "Warning: could not get file hash: %v\n", err)
-			}
-
-			info := &db.DownloadInfo{
-				SongID:     song.ID,
-				Quality:    media.Data[0].Media[0].Format,
-				Path:       filePath,
-				Hash:       hash,
-				Downloaded: time.Now(),
-			}
-			if err := info.Save(); err != nil {
-				fmt.Fprintf(os.Stderr, "Warning: could not save download info: %v\n", err)
-			}
-		}
-	}
-
-	fmt.Println(separator)
-	fmt.Println("All downloads completed")
 }

cmd/download_album.go

@@ -1,17 +0,0 @@
-package cmd
-
-import "github.com/spf13/cobra"
-
-var albumCmd = &cobra.Command{
-	Use:   "album [album_id...]",
-	Short: "Download songs from one or more albums",
-	Args:  cobra.MinimumNArgs(1),
-	Run: func(cmd *cobra.Command, args []string) {
-		validateInput()
-		downloadContent("album", args)
-	},
-}
-
-func init() {
-	downloadCmd.AddCommand(albumCmd)
-}

cmd/download_playlist.go

@@ -1,17 +0,0 @@
-package cmd
-
-import "github.com/spf13/cobra"
-
-var playlistCmd = &cobra.Command{
-	Use:   "playlist [playlist_id...]",
-	Short: "Download songs from one or more playlists",
-	Args:  cobra.MinimumNArgs(1),
-	Run: func(cmd *cobra.Command, args []string) {
-		validateInput()
-		downloadContent("playlist", args)
-	},
-}
-
-func init() {
-	downloadCmd.AddCommand(playlistCmd)
-}

cmd/root.go

@@ -1,63 +1,27 @@
 package cmd
 
 import (
-	"fmt"
+	"github.com/mathismqn/godeez/internal/app"
-	"os"
-	"path"
-	"path/filepath"
-
-	"github.com/mathismqn/godeez/internal/config"
-	"github.com/mathismqn/godeez/internal/db"
-	"github.com/mathismqn/godeez/internal/utils"
 	"github.com/spf13/cobra"
 )
 
 var (
-	cfgDir   string
+	cfgPath string
-	musicDir string
+	appCtx  *app.Context
-	appDir   string
-	cfgFile  string
 )
 
 var RootCmd = &cobra.Command{
-	Use:   "godeez",
+	Use:          "godeez",
-	Short: "GoDeez is a tool to download music from Deezer",
+	Short:        "GoDeez is a tool to download music from Deezer",
-	Run: func(cmd *cobra.Command, args []string) {
+	SilenceUsage: true,
-		cmd.Help()
+	PersistentPreRunE: func(cmd *cobra.Command, args []string) error {
+		var err error
+		appCtx, err = app.NewContext(cfgPath)
+
+		return err
 	},
 }
 
 func init() {
-	RootCmd.PersistentFlags().StringVar(&cfgFile, "config", "", "config file (default is $HOME/.godeez)")
+	RootCmd.PersistentFlags().StringVar(&cfgPath, "config", "", "config file (default is $HOME/.godeez)")
-	cobra.OnInitialize(func() {
-		initDirs()
-		config.Init(cfgFile, cfgDir)
-		db.Init(cfgDir)
-	})
-}
-
-func initDirs() {
-	home, err := os.UserHomeDir()
-	if err != nil {
-		fmt.Fprintf(os.Stderr, "Error: could not get home directory: %v\n", err)
-		os.Exit(1)
-	}
-
-	cfgDir = filepath.Join(home, ".godeez")
-	if err := utils.EnsureDir(cfgDir); err != nil {
-		fmt.Fprintf(os.Stderr, "Error: could not create app directory: %v\n", err)
-		os.Exit(1)
-	}
-
-	musicDir = filepath.Join(home, "Music")
-	if err := utils.EnsureDir(musicDir); err != nil {
-		fmt.Fprintf(os.Stderr, "Error: could not create music directory: %v\n", err)
-		os.Exit(1)
-	}
-
-	appDir = path.Join(musicDir, "GoDeez")
-	if err := utils.EnsureDir(appDir); err != nil {
-		fmt.Fprintf(os.Stderr, "Error: could not create GoDeez directory: %v\n", err)
-		os.Exit(1)
-	}
 }

internal/app/context.go

@@ -0,0 +1,53 @@
+package app
+
+import (
+	"fmt"
+	"os"
+	"path"
+	"path/filepath"
+
+	"github.com/mathismqn/godeez/internal/config"
+	"github.com/mathismqn/godeez/internal/fileutil"
+	"github.com/mathismqn/godeez/internal/store"
+)
+
+type Context struct {
+	AppDir string
+	Config *config.Config
+}
+
+func NewContext(cfgPath string) (*Context, error) {
+	home, err := os.UserHomeDir()
+	if err != nil {
+		return nil, fmt.Errorf("failed to get home directory: %w", err)
+	}
+
+	cfgDir := filepath.Join(home, ".godeez")
+	if err := fileutil.EnsureDir(cfgDir); err != nil {
+		return nil, fmt.Errorf("failed to create config directory: %w", err)
+	}
+
+	musicDir := filepath.Join(home, "Music")
+	if err := fileutil.EnsureDir(musicDir); err != nil {
+		return nil, fmt.Errorf("failed to create music directory: %w", err)
+	}
+
+	appDir := path.Join(musicDir, "GoDeez")
+	if err := fileutil.EnsureDir(appDir); err != nil {
+		return nil, fmt.Errorf("failed to create app directory: %w", err)
+	}
+
+	cfg, err := config.New(cfgPath, cfgDir)
+	if err != nil {
+		return nil, err
+	}
+
+	if err := store.OpenDB(cfgDir); err != nil {
+		return nil, err
+	}
+
+	return &Context{
+		AppDir: appDir,
+		Config: cfg,
+	}, nil
+}

internal/bpm/bpm.go

@@ -0,0 +1,176 @@
+package bpm
+
+import (
+	"bytes"
+	"context"
+	"fmt"
+	"io"
+	"net/http"
+	"net/url"
+	"regexp"
+	"strconv"
+	"strings"
+
+	"github.com/PuerkitoBio/goquery"
+)
+
+type Metrics struct {
+	BPM string
+	Key string
+}
+
+func FetchMetrics(ctx context.Context, httpClient *http.Client, artist, title, duration string) (*Metrics, error) {
+	url, err := findSongURL(ctx, httpClient, artist, title, duration)
+	if err != nil {
+		return nil, err
+	}
+
+	html, err := fetchPage(ctx, httpClient, url)
+	if err != nil {
+		return nil, err
+	}
+
+	return parseMetrics(html)
+}
+
+func findSongURL(ctx context.Context, httpClient *http.Client, artist, title, duration string) (string, error) {
+	rootUrl := "https://songbpm.com"
+	reqUrl := rootUrl + "/searches"
+
+	values := url.Values{}
+	values.Add("query", fmt.Sprintf("%s %s", artist, title))
+
+	req, err := http.NewRequestWithContext(ctx, "POST", reqUrl, bytes.NewBufferString(values.Encode()))
+	if err != nil {
+		return "", err
+	}
+	req.Header.Set("Content-Type", "application/x-www-form-urlencoded")
+	req.Header.Set("Origin", "https://songbpm.com")
+
+	resp, err := httpClient.Do(req)
+	if err != nil {
+		return "", err
+	}
+	defer resp.Body.Close()
+
+	if resp.StatusCode != http.StatusOK {
+		return "", fmt.Errorf("unexpected status code: %d", resp.StatusCode)
+	}
+
+	doc, err := goquery.NewDocumentFromReader(resp.Body)
+	if err != nil {
+		return "", err
+	}
+
+	var (
+		found bool
+		url   string
+	)
+
+	doc.Find("a.flex.flex-col").EachWithBreak(func(_ int, selection *goquery.Selection) bool {
+		lowerSelection := strings.ToLower(selection.Text())
+		lowerTitle := strings.ToLower(title)
+		lowerArtist := strings.ToLower(artist)
+		if !strings.Contains(lowerSelection, lowerTitle) || !strings.Contains(lowerSelection, lowerArtist) {
+			return true
+		}
+
+		durationStr := strings.TrimSpace(selection.Find("div.flex-1.flex-col.items-center").Eq(1).Find("span.text-2xl").Text())
+		parts := strings.Split(durationStr, ":")
+		if len(parts) != 2 {
+			return true
+		}
+		minutes, err := strconv.Atoi(parts[0])
+		if err != nil {
+			return true
+		}
+		seconds, err := strconv.Atoi(parts[1])
+		if err != nil {
+			return true
+		}
+
+		foundDuration := minutes*60 + seconds
+		duration, err := strconv.Atoi(duration)
+		if err != nil {
+			return true
+		}
+
+		if foundDuration <= (duration-2) || foundDuration >= (duration+2) {
+			return true
+		}
+
+		url = selection.AttrOr("href", "")
+		found = true
+
+		return false
+	})
+
+	if !found {
+		return "", fmt.Errorf("no data found")
+	}
+
+	return rootUrl + url, nil
+}
+
+func fetchPage(ctx context.Context, httpClient *http.Client, url string) (string, error) {
+	req, err := http.NewRequestWithContext(ctx, "GET", url, nil)
+	if err != nil {
+		return "", err
+	}
+
+	resp, err := httpClient.Do(req)
+	if err != nil {
+		return "", err
+	}
+	defer resp.Body.Close()
+
+	if resp.StatusCode != http.StatusOK {
+		return "", fmt.Errorf("unexpected status code: %d", resp.StatusCode)
+	}
+
+	body, err := io.ReadAll(resp.Body)
+	if err != nil {
+		return "", err
+	}
+
+	return string(body), nil
+}
+
+func parseMetrics(html string) (*Metrics, error) {
+	bpmRegex := regexp.MustCompile(`tempo of <span[^>]*>(\d+) BPM`)
+	bpmMatch := bpmRegex.FindStringSubmatch(html)
+
+	keyRegex := regexp.MustCompile(`with a <span[^>]*>([A-G](?:♯|#|♭|b)?(?:/[A-G](?:♯|#|♭|b)?)?)</span> key`)
+	keyMatch := keyRegex.FindStringSubmatch(html)
+
+	modeRegex := regexp.MustCompile(`a  <span[^>]*>([a-z]+)</span> mode`)
+	modeMatch := modeRegex.FindStringSubmatch(html)
+
+	if len(bpmMatch) != 2 || len(keyMatch) != 2 || len(modeMatch) != 2 {
+		return nil, fmt.Errorf("no data found")
+	}
+
+	isMinor := false
+	bpm := bpmMatch[1]
+	key := keyMatch[1]
+	if modeMatch[1] == "minor" {
+		isMinor = true
+	}
+
+	if strings.Contains(key, "/") {
+		parts := strings.Split(key, "/")
+		key = parts[0]
+	}
+
+	key = strings.ReplaceAll(key, "♯", "#")
+	key = strings.ReplaceAll(key, "♭", "b")
+
+	if isMinor && !strings.HasSuffix(key, "m") {
+		key += "m"
+	}
+
+	return &Metrics{
+		BPM: bpm,
+		Key: key,
+	}, nil
+}

internal/config/config.go

@@ -14,11 +14,9 @@ type Config struct {
 	IV        string `mapstructure:"iv"`
 }
 
-var Cfg Config
+func New(cfgPath, cfgDir string) (*Config, error) {
-
+	if cfgPath != "" {
-func Init(cfgFile, cfgDir string) {
+		viper.SetConfigFile(cfgPath)
-	if cfgFile != "" {
-		viper.SetConfigFile(cfgFile)
 	} else {
 		cfgPath := path.Join(cfgDir, "config.toml")
 		if _, err := os.Stat(cfgPath); os.IsNotExist(err) {
@@ -26,8 +24,7 @@ func Init(cfgFile, cfgDir string) {
 
 			content := []byte("arl_cookie = ''\nsecret_key = ''\niv = '0001020304050607'\n")
 			if err := os.WriteFile(cfgPath, content, 0644); err != nil {
-				fmt.Fprintf(os.Stderr, "Error: could not create config file: %v\n", err)
+				return nil, fmt.Errorf("failed to create config file: %w", err)
-				os.Exit(1)
 			}
 		}
 
@@ -38,22 +35,29 @@ func Init(cfgFile, cfgDir string) {
 	viper.SetConfigType("toml")
 	viper.AutomaticEnv()
 	if err := viper.ReadInConfig(); err != nil {
-		fmt.Fprintf(os.Stderr, "Error: could not read config file: %v\n", err)
+		return nil, fmt.Errorf("failed to read config file: %w", err)
-		os.Exit(1)
 	}
 
-	cfg := &Cfg
+	cfg := &Config{}
 	if err := viper.Unmarshal(&cfg); err != nil {
-		fmt.Fprintf(os.Stderr, "Error: could not unmarshal config file: %v\n", err)
+		return nil, fmt.Errorf("failed to unmarshal config: %w", err)
-		os.Exit(1)
 	}
 
+	if cfg.ArlCookie == "" {
+		return nil, fmt.Errorf("arl_cookie is not set in config file")
+	}
 	if cfg.SecretKey == "" {
-		fmt.Fprintln(os.Stderr, "Error: secret_key is not set in config file")
+		return nil, fmt.Errorf("secret_key is not set in config file")
-		os.Exit(1)
+	}
+	if len(cfg.SecretKey) != 16 {
+		return nil, fmt.Errorf("secret_key must be 16 bytes long")
 	}
 	if cfg.IV == "" {
-		fmt.Fprintln(os.Stderr, "Error: iv is not set in config file")
+		return nil, fmt.Errorf("iv is not set in config file")
-		os.Exit(1)
 	}
+	if len(cfg.IV) != 16 {
+		return nil, fmt.Errorf("iv must be 16 bytes long")
+	}
+
+	return cfg, nil
 }

internal/crypto/blowfish.go

@@ -3,18 +3,16 @@ package crypto
 import (
 	"crypto/cipher"
 	"crypto/md5"
-	"encoding/hex"
 	"fmt"
 
-	"github.com/mathismqn/godeez/internal/config"
 	"golang.org/x/crypto/blowfish"
 )
 
-func GetBlowfishKey(songID string) []byte {
+func GetKey(secretKey, songID string) []byte {
 	hash := md5.Sum([]byte(songID))
 	hashHex := fmt.Sprintf("%x", hash)
 
-	key := []byte(config.Cfg.SecretKey)
+	key := []byte(secretKey)
 	for i := 0; i < len(hash); i++ {
 		key[i] = key[i] ^ hashHex[i] ^ hashHex[i+16]
 	}
@@ -22,17 +20,12 @@ func GetBlowfishKey(songID string) []byte {
 	return key
 }
 
-func DecryptBlowfish(data, key []byte) ([]byte, error) {
+func Decrypt(data, key, iv []byte) ([]byte, error) {
 	block, err := blowfish.NewCipher(key)
 	if err != nil {
 		return nil, err
 	}
 
-	iv, err := hex.DecodeString(config.Cfg.IV)
-	if err != nil {
-		return nil, err
-	}
-
 	mode := cipher.NewCBCDecrypter(block, iv)
 	decrypted := make([]byte, len(data))
 	mode.CryptBlocks(decrypted, data)

internal/deezer/album.go

@@ -28,22 +28,22 @@ func (a *Album) GetType() string {
 	return "Album"
 }
 
-func (a *Album) UnmarshalData(data []byte) error {
+func (a *Album) GetTitle() string {
-	return json.Unmarshal(data, a)
+	return a.Results.Data.Title
 }
 
 func (a *Album) GetSongs() []*Song {
 	return a.Results.Songs.Data
 }
 
-func (a *Album) GetOutputPath(outputDir string) string {
+func (a *Album) GetOutputDir(outputDir string) string {
 	base := fmt.Sprintf("%s - %s", a.Results.Data.Artist, a.Results.Data.Title)
 	base, _ = filenamify.Filenamify(base, filenamify.Options{})
-	outputPath := path.Join(outputDir, base)
+	outputDir = path.Join(outputDir, base)
 
-	return outputPath
+	return outputDir
 }
 
-func (a *Album) GetTitle() string {
+func (a *Album) Unmarshal(data []byte) error {
-	return a.Results.Data.Title
+	return json.Unmarshal(data, a)
 }

internal/deezer/client.go

@@ -0,0 +1,182 @@
+package deezer
+
+import (
+	"bytes"
+	"context"
+	"encoding/json"
+	"fmt"
+	"io"
+	"net/http"
+	"strings"
+
+	"github.com/mathismqn/godeez/internal/app"
+)
+
+type Client struct {
+	AppCtx  *app.Context
+	Session *Session
+}
+
+func NewClient(ctx context.Context, appCtx *app.Context) (*Client, error) {
+	session, err := Authenticate(ctx, appCtx.Config.ArlCookie)
+	if err != nil {
+		return nil, fmt.Errorf("failed to authenticate: %w", err)
+	}
+
+	return &Client{
+		AppCtx:  appCtx,
+		Session: session,
+	}, nil
+}
+
+func (c *Client) FetchResource(ctx context.Context, ressource Resource, id string) error {
+	payload := map[string]interface{}{
+		"nb":          10000,
+		"start":       0,
+		"playlist_id": id,
+		"alb_id":      id,
+		"lang":        "en",
+		"tab":         0,
+		"tags":        true,
+		"header":      true,
+	}
+	jsonData, err := json.Marshal(payload)
+	if err != nil {
+		return err
+	}
+
+	url := fmt.Sprintf("https://www.deezer.com/ajax/gw-light.php?method=deezer.page%s&input=3&api_version=1.0&api_token=%s", ressource.GetType(), c.Session.APIToken)
+	req, err := http.NewRequestWithContext(ctx, "POST", url, bytes.NewBuffer(jsonData))
+	if err != nil {
+		return err
+	}
+
+	resp, err := c.Session.HttpClient.Do(req)
+	if err != nil {
+		return err
+	}
+	defer resp.Body.Close()
+
+	if resp.StatusCode != http.StatusOK {
+		return fmt.Errorf("unexpected status code: %d", resp.StatusCode)
+	}
+
+	body, err := io.ReadAll(resp.Body)
+	if err != nil {
+		return err
+	}
+
+	if strings.Contains(string(body), `"DATA_ERROR":"playlist::getData"`) {
+		return fmt.Errorf("invalid playlist ID")
+	}
+	if strings.Contains(string(body), `"DATA_ERROR":"album::getData"`) {
+		return fmt.Errorf("invalid album ID")
+	}
+	if strings.Contains(string(body), `"results":{}`) {
+		return fmt.Errorf("unexpected response")
+	}
+
+	return ressource.Unmarshal(body)
+}
+
+func (c *Client) FetchMedia(ctx context.Context, song *Song, quality string) (*Media, error) {
+	var formats string
+
+	switch quality {
+	case "mp3_128":
+		formats = `[{"cipher":"BF_CBC_STRIPE","format":"MP3_128"}]`
+	case "mp3_320":
+		formats = `[{"cipher":"BF_CBC_STRIPE","format":"MP3_320"}]`
+	case "flac":
+		formats = `[{"cipher":"BF_CBC_STRIPE","format":"FLAC"}]`
+	case "best":
+		formats = `[{"cipher":"BF_CBC_STRIPE","format":"FLAC"},{"cipher":"BF_CBC_STRIPE","format":"MP3_320"},{"cipher":"BF_CBC_STRIPE","format":"MP3_128"}]`
+	}
+
+	reqBody := fmt.Sprintf(`{"license_token":"%s","media":[{"type":"FULL","formats":%s}],"track_tokens":["%s"]}`, c.Session.LicenseToken, formats, song.TrackToken)
+	req, err := http.NewRequestWithContext(ctx, "POST", "https://media.deezer.com/v1/get_url", bytes.NewBuffer([]byte(reqBody)))
+	if err != nil {
+		return nil, err
+	}
+
+	resp, err := c.Session.HttpClient.Do(req)
+	if err != nil {
+		return nil, err
+	}
+	defer resp.Body.Close()
+
+	if resp.StatusCode != http.StatusOK && resp.StatusCode != http.StatusBadRequest {
+		return nil, fmt.Errorf("unexpected status code: %d", resp.StatusCode)
+	}
+
+	body, err := io.ReadAll(resp.Body)
+	if err != nil {
+		return nil, err
+	}
+
+	var media Media
+	err = json.Unmarshal(body, &media)
+	if err != nil {
+		return nil, err
+	}
+
+	if len(media.Errors) > 0 {
+		if media.Errors[0].Code == 1000 {
+			return nil, fmt.Errorf("invalid license token")
+		}
+
+		return nil, fmt.Errorf("%s", media.Errors[0].Message)
+	}
+	if len(media.Data) > 0 && len(media.Data[0].Errors) > 0 {
+		if media.Data[0].Errors[0].Code == 2002 {
+			return nil, fmt.Errorf("invalid track token")
+		}
+
+		return nil, fmt.Errorf("%s", media.Data[0].Errors[0].Message)
+	}
+
+	return &media, nil
+}
+
+func (c *Client) FetchCoverImage(ctx context.Context, song *Song) ([]byte, error) {
+	url := fmt.Sprintf("https://e-cdn-images.dzcdn.net/images/cover/%s/500x500-000000-80-0-0.jpg", song.Cover)
+	req, err := http.NewRequestWithContext(ctx, "GET", url, nil)
+	if err != nil {
+		return nil, err
+	}
+
+	resp, err := c.Session.HttpClient.Do(req)
+	if err != nil {
+		return nil, err
+	}
+	defer resp.Body.Close()
+
+	if resp.StatusCode != http.StatusOK {
+		return nil, fmt.Errorf("unexpected status code: %d", resp.StatusCode)
+	}
+
+	return io.ReadAll(resp.Body)
+}
+
+func (c *Client) GetMediaStream(ctx context.Context, media *Media, songID string) (io.ReadCloser, error) {
+	url, err := media.GetURL()
+	if err != nil {
+		return nil, err
+	}
+
+	req, err := http.NewRequestWithContext(ctx, "GET", url, nil)
+	if err != nil {
+		return nil, err
+	}
+
+	resp, err := c.Session.HttpClient.Do(req)
+	if err != nil {
+		return nil, err
+	}
+
+	if resp.StatusCode != http.StatusOK {
+		return nil, fmt.Errorf("unexpected status code: %d", resp.StatusCode)
+	}
+
+	return resp.Body, nil
+}

internal/deezer/media.go

@@ -2,10 +2,6 @@ package deezer
 
 import (
 	"fmt"
-	"net/http"
-	"os"
-
-	"github.com/mathismqn/godeez/internal/crypto"
 )
 
 type Media struct {
@@ -35,64 +31,26 @@ type Source struct {
 	Provider string `json:"provider"`
 }
 
-const ChunkSize = 2048
+func (m *Media) GetURL() (string, error) {
-
+	if len(m.Data) == 0 || len(m.Data[0].Media) == 0 || len(m.Data[0].Media[0].Sources) == 0 {
-func (m *Media) Download(url, path, songID string) error {
+		return "", fmt.Errorf("no media sources found")
-	resp, err := http.Get(url)
-	if err != nil {
-		return err
-	}
-	defer resp.Body.Close()
-
-	if resp.StatusCode != http.StatusOK {
-		return fmt.Errorf("unexpected status code: %d", resp.StatusCode)
 	}
 
-	file, err := os.Create(path)
+	url := m.Data[0].Media[0].Sources[0].URL
-	if err != nil {
+	for _, source := range m.Data[0].Media[0].Sources {
-		return err
+		if source.Provider == "ak" {
-	}
+			url = source.URL
-	defer file.Close()
-
-	key := crypto.GetBlowfishKey(songID)
-	buffer := make([]byte, ChunkSize)
-
-	for chunk := 0; ; chunk++ {
-		totalRead := 0
-		for totalRead < ChunkSize {
-			n, err := resp.Body.Read(buffer[totalRead:])
-			if err != nil {
-				if err.Error() == "EOF" {
-					break
-				}
-				return err
-			}
-
-			if n > 0 {
-				totalRead += n
-			}
-		}
-
-		if totalRead == 0 {
-			break
-		}
-
-		if chunk%3 == 0 && totalRead == ChunkSize {
-			buffer, err = crypto.DecryptBlowfish(buffer, key)
-			if err != nil {
-				return err
-			}
-		}
-
-		_, err = file.Write(buffer[:totalRead])
-		if err != nil {
-			return err
-		}
-
-		if totalRead < ChunkSize {
 			break
 		}
 	}
 
-	return nil
+	return url, nil
+}
+
+func (m *Media) GetFormat() (string, error) {
+	if len(m.Data) == 0 || len(m.Data[0].Media) == 0 {
+		return "", fmt.Errorf("no media format found")
+	}
+
+	return m.Data[0].Media[0].Format, nil
 }

internal/deezer/playlist.go

@@ -24,21 +24,21 @@ func (p *Playlist) GetType() string {
 	return "Playlist"
 }
 
-func (p *Playlist) UnmarshalData(data []byte) error {
+func (p *Playlist) GetTitle() string {
-	return json.Unmarshal(data, p)
+	return p.Results.Data.Title
 }
 
 func (p *Playlist) GetSongs() []*Song {
 	return p.Results.Songs.Data
 }
 
-func (p *Playlist) GetOutputPath(outputDir string) string {
+func (p *Playlist) GetOutputDir(outputDir string) string {
 	p.Results.Data.Title, _ = filenamify.Filenamify(p.Results.Data.Title, filenamify.Options{})
-	outputPath := path.Join(outputDir, p.Results.Data.Title)
+	outputDir = path.Join(outputDir, p.Results.Data.Title)
 
-	return outputPath
+	return outputDir
 }
 
-func (p *Playlist) GetTitle() string {
+func (p *Playlist) Unmarshal(data []byte) error {
-	return p.Results.Data.Title
+	return json.Unmarshal(data, p)
 }

internal/deezer/resource.go

@@ -1,65 +1,9 @@
 package deezer
 
-import (
-	"bytes"
-	"encoding/json"
-	"fmt"
-	"io"
-	"net/http"
-	"strings"
-)
-
 type Resource interface {
-	GetType() string
-	UnmarshalData(data []byte) error
-	GetSongs() []*Song
-	GetOutputPath(outputDir string) string
 	GetTitle() string
-}
+	GetType() string
-
+	GetSongs() []*Song
-func (s *Session) GetData(r Resource, id string) error {
+	GetOutputDir(outputDir string) string
-	payload := map[string]interface{}{
+	Unmarshal(data []byte) error
-		"nb":          10000,
-		"start":       0,
-		"playlist_id": id,
-		"alb_id":      id,
-		"lang":        "en",
-		"tab":         0,
-		"tags":        true,
-		"header":      true,
-	}
-	jsonData, err := json.Marshal(payload)
-	if err != nil {
-		return err
-	}
-
-	url := fmt.Sprintf("https://www.deezer.com/ajax/gw-light.php?method=deezer.page%s&input=3&api_version=1.0&api_token=%s", r.GetType(), s.APIToken)
-	req, err := http.NewRequest("POST", url, bytes.NewBuffer(jsonData))
-	if err != nil {
-		return err
-	}
-
-	resp, err := s.Client.Do(req)
-	if err != nil {
-		return err
-	}
-	defer resp.Body.Close()
-
-	if resp.StatusCode != http.StatusOK {
-		return fmt.Errorf("unexpected status code: %d", resp.StatusCode)
-	}
-
-	body, _ := io.ReadAll(resp.Body)
-
-	if strings.Contains(string(body), `"DATA_ERROR":"playlist::getData"`) {
-		return fmt.Errorf("invalid playlist ID")
-	}
-	if strings.Contains(string(body), `"DATA_ERROR":"album::getData"`) {
-		return fmt.Errorf("invalid album ID")
-	}
-	if strings.Contains(string(body), `"results":{}`) {
-		return fmt.Errorf("unexpected response")
-	}
-
-	return r.UnmarshalData(body)
 }

internal/deezer/session.go

@@ -1,11 +1,13 @@
 package deezer
 
 import (
+	"context"
 	"encoding/json"
 	"fmt"
 	"io"
 	"net/http"
 	"net/http/cookiejar"
+	"time"
 )
 
 type UserDataResponse struct {
@@ -26,20 +28,21 @@ type Session struct {
 	ArlCookie    string
 	APIToken     string
 	LicenseToken string
-	Client       *http.Client
+	HttpClient   *http.Client
 }
 
-func Authenticate(arlCookie string) (*Session, error) {
+func Authenticate(ctx context.Context, arlCookie string) (*Session, error) {
 	jar, err := cookiejar.New(nil)
 	if err != nil {
 		return nil, err
 	}
 	client := &http.Client{
-		Jar: jar,
+		Timeout: 20 * time.Second,
+		Jar:     jar,
 	}
 
 	url := "https://www.deezer.com/ajax/gw-light.php?method=deezer.getUserData&input=3&api_version=1.0&api_token="
-	req, err := http.NewRequest("GET", url, nil)
+	req, err := http.NewRequestWithContext(ctx, "GET", url, nil)
 	if err != nil {
 		return nil, err
 	}
@@ -59,7 +62,10 @@ func Authenticate(arlCookie string) (*Session, error) {
 		return nil, fmt.Errorf("unexpected status code: %d", resp.StatusCode)
 	}
 
-	body, _ := io.ReadAll(resp.Body)
+	body, err := io.ReadAll(resp.Body)
+	if err != nil {
+		return nil, err
+	}
 
 	var res UserDataResponse
 	if err := json.Unmarshal(body, &res); err != nil {
@@ -77,6 +83,6 @@ func Authenticate(arlCookie string) (*Session, error) {
 		ArlCookie:    arlCookie,
 		APIToken:     res.Results.APIToken,
 		LicenseToken: res.Results.User.Options.LicenseToken,
-		Client:       client,
+		HttpClient:   client,
 	}, nil
 }

internal/deezer/song.go

@@ -1,17 +1,10 @@
 package deezer
 
 import (
-	"bytes"
-	"encoding/json"
 	"fmt"
-	"io"
-	"net/http"
-	"net/url"
-	"regexp"
-	"strconv"
 	"strings"
 
-	"github.com/PuerkitoBio/goquery"
+	"github.com/flytam/filenamify"
 )
 
 type Song struct {
@@ -32,216 +25,27 @@ type Song struct {
 	TrackToken  string `json:"TRACK_TOKEN"`
 }
 
-func (s *Song) GetMediaData(licenseToken, quality string) (*Media, error) {
+func (s *Song) GetTitle() string {
-	var formats string
+	songTitle := s.Title
-
+	if s.Version != "" {
-	switch quality {
+		songTitle = fmt.Sprintf("%s %s", s.Title, s.Version)
-	case "mp3_128":
-		formats = `[{"cipher":"BF_CBC_STRIPE","format":"MP3_128"}]`
-	case "mp3_320":
-		formats = `[{"cipher":"BF_CBC_STRIPE","format":"MP3_320"}]`
-	case "flac":
-		formats = `[{"cipher":"BF_CBC_STRIPE","format":"FLAC"}]`
-	case "best":
-		formats = `[{"cipher":"BF_CBC_STRIPE","format":"FLAC"},{"cipher":"BF_CBC_STRIPE","format":"MP3_320"},{"cipher":"BF_CBC_STRIPE","format":"MP3_128"}]`
 	}
 
-	reqBody := fmt.Sprintf(`{"license_token":"%s","media":[{"type":"FULL","formats":%s}],"track_tokens":["%s"]}`, licenseToken, formats, s.TrackToken)
+	return songTitle
-	resp, err := http.Post("https://media.deezer.com/v1/get_url", "application/json", bytes.NewBuffer([]byte(reqBody)))
-	if err != nil {
-		return nil, err
-	}
-	defer resp.Body.Close()
-
-	if resp.StatusCode != http.StatusOK && resp.StatusCode != http.StatusBadRequest {
-		return nil, fmt.Errorf("unexpected status code: %d", resp.StatusCode)
-	}
-
-	body, _ := io.ReadAll(resp.Body)
-
-	var media Media
-	err = json.Unmarshal(body, &media)
-	if err != nil {
-		return nil, err
-	}
-
-	if len(media.Errors) > 0 {
-		if media.Errors[0].Code == 1000 {
-			return nil, fmt.Errorf("invalid license token")
-		}
-
-		return nil, fmt.Errorf("%s", media.Errors[0].Message)
-	}
-	if len(media.Data) > 0 && len(media.Data[0].Errors) > 0 {
-		if media.Data[0].Errors[0].Code == 2002 {
-			return nil, fmt.Errorf("invalid track token")
-		}
-
-		return nil, fmt.Errorf("%s", media.Data[0].Errors[0].Message)
-	}
-
-	return &media, nil
 }
 
-func (s *Song) GetCoverImage() ([]byte, error) {
+func (s *Song) GetFileName(resourceType string, song *Song, media *Media) string {
-	url := fmt.Sprintf("https://e-cdn-images.dzcdn.net/images/cover/%s/500x500-000000-80-0-0.jpg", s.Cover)
+	ext := "mp3"
-	resp, err := http.Get(url)
+	if media.Data[0].Media[0].Format == "FLAC" {
-	if err != nil {
+		ext = "flac"
-		return nil, err
 	}
-	defer resp.Body.Close()
+	trackNumber := ""
-
+	if resourceType == "album" {
-	if resp.StatusCode != http.StatusOK {
+		trackNumber = song.TrackNumber + "."
-		return nil, fmt.Errorf("unexpected status code: %d", resp.StatusCode)
 	}
 
-	return io.ReadAll(resp.Body)
+	fileName := fmt.Sprintf("%s %s - %s.%s", trackNumber, s.GetTitle(), strings.Join(song.Contributors.MainArtists, ", "), ext)
-}
+	fileName, _ = filenamify.Filenamify(fileName, filenamify.Options{})
 
-func (s *Song) GetTempoAndKey() (string, string, error) {
+	return fileName
-	client := &http.Client{}
-	link, err := s.findSongLink(client)
-	if err != nil {
-		return "", "", err
-	}
-
-	html, err := fetchPage(client, link)
-	if err != nil {
-		return "", "", err
-	}
-
-	return parseBPMAndKey(html)
-}
-
-func (s *Song) findSongLink(client *http.Client) (string, error) {
-	rootUrl := "https://songbpm.com"
-	reqUrl := rootUrl + "/searches"
-
-	values := url.Values{}
-	values.Add("query", fmt.Sprintf("%s %s %s", s.Artist, s.Title, s.Version))
-
-	req, err := http.NewRequest("POST", reqUrl, bytes.NewBufferString(values.Encode()))
-	if err != nil {
-		return "", err
-	}
-	req.Header.Set("Content-Type", "application/x-www-form-urlencoded")
-	req.Header.Set("Origin", "https://songbpm.com")
-
-	resp, err := client.Do(req)
-	if err != nil {
-		return "", err
-	}
-	defer resp.Body.Close()
-
-	if resp.StatusCode != http.StatusOK {
-		return "", fmt.Errorf("unexpected status code: %d", resp.StatusCode)
-	}
-
-	doc, err := goquery.NewDocumentFromReader(resp.Body)
-	if err != nil {
-		return "", err
-	}
-
-	var found bool
-	var link string
-
-	doc.Find("a.flex.flex-col").Each(func(i int, selection *goquery.Selection) {
-		if strings.Contains(selection.Text(), s.Title) && strings.Contains(selection.Text(), s.Artist) {
-			foundArtist := selection.Find("p.text-sm.font-light.uppercase").Text()
-			foundTitle := selection.Find("p.pr-2.text-lg").Text()
-
-			if strings.Contains(strings.ToLower(foundArtist), strings.ToLower(s.Artist)) && strings.Contains(strings.ToLower(foundTitle), strings.ToLower(s.Title)) {
-				durationStr := strings.TrimSpace(selection.Find("div.flex-1.flex-col.items-center").Eq(1).Find("span.text-2xl").Text())
-				parts := strings.Split(durationStr, ":")
-				if len(parts) != 2 {
-					return
-				}
-				minutes, err := strconv.Atoi(parts[0])
-				if err != nil {
-					fmt.Println(err)
-					return
-				}
-				seconds, err := strconv.Atoi(parts[1])
-				if err != nil {
-					return
-				}
-
-				foundDuration := minutes*60 + seconds
-				duration, err := strconv.Atoi(s.Duration)
-				if err != nil {
-					return
-				}
-
-				if foundDuration > (duration-2) || foundDuration < (duration+2) {
-					link = selection.AttrOr("href", "")
-					found = true
-
-					return
-				}
-			}
-		}
-	})
-
-	if !found {
-		return "", fmt.Errorf("no data found")
-	}
-
-	return rootUrl + link, nil
-}
-
-func fetchPage(client *http.Client, link string) (string, error) {
-	req, err := http.NewRequest("GET", link, nil)
-	if err != nil {
-		return "", err
-	}
-
-	resp, err := client.Do(req)
-	if err != nil {
-		return "", err
-	}
-	defer resp.Body.Close()
-
-	if resp.StatusCode != http.StatusOK {
-		return "", fmt.Errorf("unexpected status code: %d", resp.StatusCode)
-	}
-
-	body, _ := io.ReadAll(resp.Body)
-
-	return string(body), nil
-}
-
-func parseBPMAndKey(html string) (string, string, error) {
-	bpmRegex := regexp.MustCompile(`tempo of <span[^>]*>(\d+) BPM`)
-	bpmMatch := bpmRegex.FindStringSubmatch(html)
-
-	keyRegex := regexp.MustCompile(`with a <span[^>]*>([A-G](?:♯|#|♭|b)?(?:/[A-G](?:♯|#|♭|b)?)?)</span> key`)
-	keyMatch := keyRegex.FindStringSubmatch(html)
-
-	modeRegex := regexp.MustCompile(`a  <span[^>]*>([a-z]+)</span> mode`)
-	modeMatch := modeRegex.FindStringSubmatch(html)
-
-	if len(bpmMatch) != 2 || len(keyMatch) != 2 || len(modeMatch) != 2 {
-		return "", "", fmt.Errorf("no data found")
-	}
-
-	isMinor := false
-	bpm := bpmMatch[1]
-	key := keyMatch[1]
-	if modeMatch[1] == "minor" {
-		isMinor = true
-	}
-
-	if strings.Contains(key, "/") {
-		parts := strings.Split(key, "/")
-		key = parts[0]
-	}
-
-	key = strings.ReplaceAll(key, "♯", "#")
-	key = strings.ReplaceAll(key, "♭", "b")
-
-	if isMinor && !strings.HasSuffix(key, "m") {
-		key += "m"
-	}
-
-	return bpm, key, nil
 }

internal/downloader/client.go

@@ -0,0 +1,275 @@
+package downloader
+
+import (
+	"context"
+	"encoding/hex"
+	"errors"
+	"fmt"
+	"io"
+	"os"
+	"path"
+	"sync"
+	"time"
+
+	"github.com/mathismqn/godeez/internal/app"
+	"github.com/mathismqn/godeez/internal/bpm"
+	"github.com/mathismqn/godeez/internal/crypto"
+	"github.com/mathismqn/godeez/internal/deezer"
+	"github.com/mathismqn/godeez/internal/fileutil"
+	"github.com/mathismqn/godeez/internal/store"
+	"github.com/mathismqn/godeez/internal/tags"
+)
+
+const ChunkSize = 2048
+
+type Client struct {
+	appCtx       *app.Context
+	resourceType string
+	deezerClient *deezer.Client
+
+	hashIndexOnce sync.Once
+	hashIndex     *fileutil.HashIndex
+	hashIndexErr  error
+}
+
+func New(appCtx *app.Context, resourceType string) *Client {
+	return &Client{
+		appCtx:       appCtx,
+		resourceType: resourceType,
+		deezerClient: nil,
+	}
+}
+
+func (c *Client) Run(ctx context.Context, opts Options, ids []string) error {
+	var err error
+	c.deezerClient, err = deezer.NewClient(ctx, c.appCtx)
+	if err != nil {
+		return err
+	}
+
+	for _, id := range ids {
+		if ctx.Err() != nil {
+			return ctx.Err()
+		}
+
+		var resource deezer.Resource
+
+		switch c.resourceType {
+		case "album":
+			resource = &deezer.Album{}
+		case "playlist":
+			resource = &deezer.Playlist{}
+		default:
+			return fmt.Errorf("unsupported resource type: %s", c.resourceType)
+		}
+
+		if err := c.deezerClient.FetchResource(ctx, resource, id); err != nil {
+			return fmt.Errorf("failed to fetch resource: %w", err)
+		}
+
+		songs := resource.GetSongs()
+		if len(songs) == 0 {
+			return fmt.Errorf("%s has no songs", c.resourceType)
+		}
+
+		outputDir := resource.GetOutputDir(opts.OutputDir)
+		if err := fileutil.EnsureDir(outputDir); err != nil {
+			return fmt.Errorf("failed to create output directory: %w", err)
+		}
+
+		for _, song := range songs {
+			if ctx.Err() != nil {
+				return ctx.Err()
+			}
+
+			if err := c.downloadSong(ctx, resource, song, opts, outputDir); err != nil {
+				if errors.Is(err, context.Canceled) || errors.Is(err, context.DeadlineExceeded) {
+					return err
+				}
+
+				fmt.Fprintf(os.Stderr, "Error: failed to download %s: %v\n", song.Title, err)
+				continue
+			}
+		}
+	}
+
+	return nil
+}
+
+func (c *Client) downloadSong(ctx context.Context, resource deezer.Resource, song *deezer.Song, opts Options, outputDir string) error {
+	media, err := c.deezerClient.FetchMedia(ctx, song, opts.Quality)
+	if err != nil {
+		return err
+	}
+
+	fileName := song.GetFileName(c.resourceType, song, media)
+	outputPath := path.Join(outputDir, fileName)
+
+	mediaFormat, err := media.GetFormat()
+	if err != nil {
+		return err
+	}
+
+	if _, skip := c.shouldSkipDownload(ctx, song.ID, mediaFormat); skip {
+		return nil
+	}
+
+	metricsChan := make(chan *bpm.Metrics, 1)
+	errChan := make(chan error, 1)
+
+	go func() {
+		metrics, err := bpm.FetchMetrics(ctx, c.deezerClient.Session.HttpClient, song.Artist, song.GetTitle(), song.Duration)
+		if err != nil {
+			errChan <- err
+			return
+		}
+
+		metricsChan <- metrics
+	}()
+
+	stream, err := c.deezerClient.GetMediaStream(ctx, media, song.ID)
+	if err != nil {
+		return fmt.Errorf("media stream unavailable: %w", err)
+	}
+
+	dlCtx, cancel := context.WithTimeout(ctx, 2*time.Minute)
+	defer cancel()
+
+	if err := c.streamToFile(dlCtx, stream, outputPath, song.ID); err != nil {
+		fileutil.DeleteFile(outputPath)
+
+		return fmt.Errorf("unable to write to file: %w", err)
+	}
+
+	metrics := &bpm.Metrics{}
+	select {
+	case metrics = <-metricsChan:
+		fmt.Printf("BPM: %s, Key: %s\n", metrics.BPM, metrics.Key)
+	case err := <-errChan:
+
+		fmt.Printf("Warning: failed to fetch BPM and key: %v\n", err)
+	}
+
+	cover, err := c.deezerClient.FetchCoverImage(ctx, song)
+	if err != nil {
+		fmt.Printf("Warning: failed to fetch cover image: %v\n", err)
+	}
+
+	c.finalizeDownload(resource, song, outputPath, mediaFormat, cover, metrics)
+
+	return nil
+}
+
+func (c *Client) shouldSkipDownload(ctx context.Context, songID, mediaFormat string) (string, bool) {
+	if existing, err := store.GetDownloadInfo(songID); err == nil && existing.Quality == mediaFormat {
+		if fileutil.FileExists(existing.Path) {
+			return existing.Path, true
+		}
+		if existing.Hash != "" {
+			if err := c.initHashIndex(ctx); err == nil {
+				if foundPath, ok := c.hashIndex.Find(existing.Hash); ok {
+					existing.Path = foundPath
+					_ = existing.Save()
+
+					return foundPath, true
+				}
+			}
+		}
+	}
+
+	return "", false
+}
+
+func (c *Client) streamToFile(ctx context.Context, stream io.ReadCloser, outputPath, songID string) error {
+	defer stream.Close()
+
+	file, err := os.Create(outputPath)
+	if err != nil {
+		return err
+	}
+	defer file.Close()
+
+	key := crypto.GetKey(c.appCtx.Config.SecretKey, songID)
+	iv, err := hex.DecodeString(c.appCtx.Config.IV)
+	if err != nil {
+		return err
+	}
+
+	buffer := make([]byte, ChunkSize)
+	for chunk := 0; ; chunk++ {
+		select {
+		case <-ctx.Done():
+			return ctx.Err()
+		default:
+			// continue
+		}
+
+		totalRead := 0
+		for totalRead < ChunkSize {
+			n, err := stream.Read(buffer[totalRead:])
+			if err != nil {
+				if errors.Is(err, io.EOF) {
+					break
+				}
+				return err
+			}
+
+			if n > 0 {
+				totalRead += n
+			}
+		}
+
+		if totalRead == 0 {
+			break
+		}
+
+		if chunk%3 == 0 && totalRead == ChunkSize {
+			buffer, err = crypto.Decrypt(buffer, key, iv)
+			if err != nil {
+				return err
+			}
+		}
+
+		_, err = file.Write(buffer[:totalRead])
+		if err != nil {
+			return err
+		}
+
+		if totalRead < ChunkSize {
+			break
+		}
+	}
+
+	return nil
+}
+
+func (c *Client) finalizeDownload(resource deezer.Resource, song *deezer.Song, outputPath, mediaFormat string, cover []byte, metrics *bpm.Metrics) {
+	if err := tags.AddTags(resource, song, cover, outputPath, metrics.BPM, metrics.Key); err != nil {
+		fmt.Printf("Warning: failed to add tags: %v\n", err)
+	}
+
+	hash, err := fileutil.GetFileHash(outputPath)
+	if err != nil {
+		fmt.Printf("Warning: failed to get file hash: %v\n", err)
+	}
+
+	info := &store.DownloadInfo{
+		SongID:     song.ID,
+		Quality:    mediaFormat,
+		Path:       outputPath,
+		Hash:       hash,
+		Downloaded: time.Now(),
+	}
+
+	if err := info.Save(); err != nil {
+		fmt.Printf("Warning: failed to save download info: %v\n", err)
+	}
+}
+
+func (c *Client) initHashIndex(ctx context.Context) error {
+	c.hashIndexOnce.Do(func() {
+		c.hashIndex, c.hashIndexErr = fileutil.NewHashIndex(ctx, c.appCtx.AppDir)
+	})
+
+	return c.hashIndexErr
+}

internal/downloader/options.go

@@ -0,0 +1,33 @@
+package downloader
+
+import (
+	"fmt"
+)
+
+var validQualities = map[string]bool{
+	"mp3_128": true,
+	"mp3_320": true,
+	"flac":    true,
+	"best":    true,
+}
+
+type Options struct {
+	OutputDir string
+	Quality   string
+}
+
+func (o *Options) Validate(appDir string) error {
+	if o.OutputDir == "" {
+		o.OutputDir = appDir
+	}
+
+	if o.Quality == "" {
+		o.Quality = "best"
+	}
+
+	if !validQualities[o.Quality] {
+		return fmt.Errorf("invalid quality option: %s", o.Quality)
+	}
+
+	return nil
+}

internal/fileutil/file.go

@@ -0,0 +1,52 @@
+package fileutil
+
+import (
+	"crypto/sha256"
+	"fmt"
+	"io"
+	"os"
+)
+
+func EnsureDir(path string) error {
+	info, err := os.Stat(path)
+	if os.IsNotExist(err) {
+		return os.MkdirAll(path, 0755)
+	}
+	if err != nil {
+		return err
+	}
+	if !info.IsDir() {
+		return fmt.Errorf("file already exists at %s", path)
+	}
+
+	return nil
+}
+
+func FileExists(path string) bool {
+	info, err := os.Stat(path)
+
+	return err == nil && !info.IsDir()
+}
+
+func DeleteFile(path string) error {
+	if !FileExists(path) {
+		return nil
+	}
+
+	return os.Remove(path)
+}
+
+func GetFileHash(path string) (string, error) {
+	file, err := os.Open(path)
+	if err != nil {
+		return "", err
+	}
+	defer file.Close()
+
+	hash := sha256.New()
+	if _, err := io.Copy(hash, file); err != nil {
+		return "", err
+	}
+
+	return fmt.Sprintf("%x", hash.Sum(nil)), nil
+}

internal/fileutil/hashindex.go

@@ -0,0 +1,56 @@
+package fileutil
+
+import (
+	"context"
+	"crypto/sha256"
+	"encoding/hex"
+	"io"
+	"os"
+	"path/filepath"
+)
+
+type HashIndex struct {
+	files map[string]string
+}
+
+func NewHashIndex(ctx context.Context, root string) (*HashIndex, error) {
+	index := &HashIndex{files: make(map[string]string)}
+
+	err := filepath.Walk(root, func(path string, info os.FileInfo, err error) error {
+		if ctx.Err() != nil {
+			return ctx.Err()
+		}
+
+		if err != nil || info.IsDir() {
+			return nil
+		}
+
+		file, err := os.Open(path)
+		if err != nil {
+			return nil
+		}
+		defer file.Close()
+
+		h := sha256.New()
+		if _, err := io.Copy(h, file); err != nil {
+			return nil
+		}
+
+		sum := hex.EncodeToString(h.Sum(nil))
+		index.files[sum] = path
+
+		return nil
+	})
+
+	if err != nil {
+		return nil, err
+	}
+
+	return index, nil
+}
+
+func (h *HashIndex) Find(hash string) (string, bool) {
+	path, ok := h.files[hash]
+
+	return path, ok
+}

internal/store/download_info.go

@@ -1,4 +1,4 @@
-package db
+package store
 
 import (
 	"encoding/json"
@@ -16,7 +16,7 @@ type DownloadInfo struct {
 	Downloaded time.Time `json:"downloaded_at"`
 }
 
-func Get(songID string) (*DownloadInfo, error) {
+func GetDownloadInfo(songID string) (*DownloadInfo, error) {
 	var info DownloadInfo
 
 	if err := db.View(func(tx *bbolt.Tx) error {

internal/store/store.go

@@ -1,8 +1,7 @@
-package db
+package store
 
 import (
 	"fmt"
-	"os"
 	"path"
 
 	bolt "go.etcd.io/bbolt"
@@ -13,21 +12,21 @@ var (
 	trackBucket = []byte("tracks")
 )
 
-func Init(cfgDir string) {
+func OpenDB(cfgDir string) error {
 	var err error
 
 	dbPath := path.Join(cfgDir, "tracks.db")
 	db, err = bolt.Open(dbPath, 0600, nil)
 	if err != nil {
-		fmt.Fprintf(os.Stderr, "Error: could not open database: %v\n", err)
+		return fmt.Errorf("failed to open database: %w", err)
-		os.Exit(1)
 	}
 
 	if err := db.Update(func(tx *bolt.Tx) error {
 		_, err := tx.CreateBucketIfNotExists(trackBucket)
 		return err
 	}); err != nil {
-		fmt.Fprintf(os.Stderr, "Error: could not create bucket: %v\n", err)
+		return fmt.Errorf("failed to create bucket: %w", err)
-		os.Exit(1)
 	}
+
+	return nil
 }

internal/tags/flac.go

@@ -10,13 +10,13 @@ import (
 	"github.com/mathismqn/godeez/internal/deezer"
 )
 
-type FLACTagger struct {
+type flacTagger struct {
-	File  *flac.File
+	file  *flac.File
-	Cmts  *flacvorbis.MetaDataBlockVorbisComment
+	cmts  *flacvorbis.MetaDataBlockVorbisComment
-	Index int
+	index int
 }
 
-func (t *FLACTagger) AddTags(resource deezer.Resource, song *deezer.Song, cover []byte, path, tempo, key string) error {
+func (t *flacTagger) addTags(resource deezer.Resource, song *deezer.Song, cover []byte, path, tempo, key string) error {
 	if album, ok := resource.(*deezer.Album); ok {
 		dateParts := strings.Split(album.Results.Data.PhysicalReleaseDate, "-")
 		if len(dateParts) == 3 {
@@ -43,11 +43,11 @@ func (t *FLACTagger) AddTags(resource deezer.Resource, song *deezer.Song, cover
 	t.addTag("KEY", key)
 	t.addTag("INITIALKEY", key)
 
-	cmtsmeta := t.Cmts.Marshal()
+	cmtsmeta := t.cmts.Marshal()
-	if t.Index > 0 {
+	if t.index > 0 {
-		t.File.Meta[t.Index] = &cmtsmeta
+		t.file.Meta[t.index] = &cmtsmeta
 	} else {
-		t.File.Meta = append(t.File.Meta, &cmtsmeta)
+		t.file.Meta = append(t.file.Meta, &cmtsmeta)
 	}
 
 	picture, err := flacpicture.NewFromImageData(flacpicture.PictureTypeFrontCover, "Front cover", cover, "image/jpeg")
@@ -55,20 +55,20 @@ func (t *FLACTagger) AddTags(resource deezer.Resource, song *deezer.Song, cover
 		return err
 	}
 	picturemeta := picture.Marshal()
-	t.File.Meta = append(t.File.Meta, &picturemeta)
+	t.file.Meta = append(t.file.Meta, &picturemeta)
 
 	return t.saveTags(path)
 }
 
-func (t *FLACTagger) addTag(name, value string) {
+func (t *flacTagger) addTag(name, value string) {
 	if value != "" {
-		t.Cmts.Add(name, value)
+		t.cmts.Add(name, value)
 	}
 }
 
-func (t *FLACTagger) saveTags(path string) error {
+func (t *flacTagger) saveTags(path string) error {
 	tempPath := path + ".tmp"
-	t.File.Save(tempPath)
+	t.file.Save(tempPath)
 
 	return os.Rename(tempPath, path)
 }

internal/tags/id3v2.go

@@ -9,14 +9,17 @@ import (
 	"github.com/mathismqn/godeez/internal/deezer"
 )
 
-type ID3v2Tagger struct {
+type id3v2Tagger struct {
-	Tag *id3v2.Tag
+	tag *id3v2.Tag
 }
 
-func (t *ID3v2Tagger) AddTags(resource deezer.Resource, song *deezer.Song, cover []byte, path, tempo, key string) error {
+func (t *id3v2Tagger) addTags(resource deezer.Resource, song *deezer.Song, cover []byte, path, tempo, key string) error {
-	defer t.Tag.Close()
+	defer t.tag.Close()
 
-	duration, _ := strconv.Atoi(song.Duration)
+	duration, err := strconv.Atoi(song.Duration)
+	if err != nil {
+		return err
+	}
 	song.Duration = fmt.Sprintf("%d", duration*1000)
 
 	if album, ok := resource.(*deezer.Album); ok {
@@ -41,30 +44,30 @@ func (t *ID3v2Tagger) AddTags(resource deezer.Resource, song *deezer.Song, cover
 	t.addTag("TKEY", key)
 
 	frame := id3v2.PictureFrame{
-		Encoding:    t.Tag.DefaultEncoding(),
+		Encoding:    t.tag.DefaultEncoding(),
 		MimeType:    "image/jpeg",
 		PictureType: id3v2.PTFrontCover,
 		Description: "Cover",
 		Picture:     cover,
 	}
-	t.Tag.AddAttachedPicture(frame)
+	t.tag.AddAttachedPicture(frame)
 
-	return t.Tag.Save()
+	return t.tag.Save()
 }
 
-func (t *ID3v2Tagger) addTag(name, value string) {
+func (t *id3v2Tagger) addTag(name, value string) {
 	if value != "" {
-		t.Tag.AddTextFrame(name, t.Tag.DefaultEncoding(), value)
+		t.tag.AddTextFrame(name, t.tag.DefaultEncoding(), value)
 	}
 }
 
-func (t *ID3v2Tagger) addTXXXTag(description, value string) {
+func (t *id3v2Tagger) addTXXXTag(description, value string) {
 	if value != "" {
 		udf := id3v2.UserDefinedTextFrame{
-			Encoding:    t.Tag.DefaultEncoding(),
+			Encoding:    t.tag.DefaultEncoding(),
 			Description: description,
 			Value:       value,
 		}
-		t.Tag.AddUserDefinedTextFrame(udf)
+		t.tag.AddUserDefinedTextFrame(udf)
 	}
 }

internal/tags/tags.go

@@ -9,18 +9,19 @@ import (
 	"github.com/mathismqn/godeez/internal/deezer"
 )
 
-type Tagger interface {
+type tagger interface {
-	AddTags(resource deezer.Resource, song *deezer.Song, cover []byte, path, tempo, key string) error
+	addTags(resource deezer.Resource, song *deezer.Song, cover []byte, path, tempo, key string) error
 }
 
-func NewTagger(filePath string) (Tagger, error) {
+func newTagger(filePath string) (tagger, error) {
 	ext := path.Ext(filePath)
 	if ext == ".mp3" {
 		tag, err := id3v2.Open(filePath, id3v2.Options{Parse: true})
 		if err != nil {
 			return nil, err
 		}
-		return &ID3v2Tagger{Tag: tag}, nil
+
+		return &id3v2Tagger{tag: tag}, nil
 	}
 
 	file, err := flac.ParseFile(filePath)
@@ -35,18 +36,14 @@ func NewTagger(filePath string) (Tagger, error) {
 		cmts = flacvorbis.New()
 	}
 
-	return &FLACTagger{File: file, Cmts: cmts, Index: idx}, nil
+	return &flacTagger{file: file, cmts: cmts, index: idx}, nil
 }
 
-func AddTags(resource deezer.Resource, song *deezer.Song, filePath, tempo, key string) error {
+func AddTags(resource deezer.Resource, song *deezer.Song, cover []byte, filePath, tempo, key string) error {
-	tagger, err := NewTagger(filePath)
+	tagger, err := newTagger(filePath)
-	if err != nil {
-		return err
-	}
-	cover, err := song.GetCoverImage()
 	if err != nil {
 		return err
 	}
 
-	return tagger.AddTags(resource, song, cover, filePath, tempo, key)
+	return tagger.addTags(resource, song, cover, filePath, tempo, key)
 }

internal/utils/dir.go

@@ -1,21 +0,0 @@
-package utils
-
-import (
-	"fmt"
-	"os"
-)
-
-func EnsureDir(path string) error {
-	info, err := os.Stat(path)
-	if os.IsNotExist(err) {
-		return os.MkdirAll(path, 0755)
-	}
-	if err != nil {
-		return err
-	}
-	if !info.IsDir() {
-		return fmt.Errorf("file already exists at %s", path)
-	}
-
-	return nil
-}

internal/utils/file.go

@@ -1,73 +0,0 @@
-package utils
-
-import (
-	"crypto/sha256"
-	"encoding/hex"
-	"fmt"
-	"io"
-	"os"
-	"path/filepath"
-)
-
-func FileExists(path string) bool {
-	info, err := os.Stat(path)
-
-	return err == nil && !info.IsDir()
-}
-
-func DeleteFile(path string) error {
-	if !FileExists(path) {
-		return nil
-	}
-
-	return os.Remove(path)
-}
-
-func GetFileHash(path string) (string, error) {
-	file, err := os.Open(path)
-	if err != nil {
-		return "", err
-	}
-	defer file.Close()
-
-	hash := sha256.New()
-	if _, err := io.Copy(hash, file); err != nil {
-		return "", err
-	}
-
-	return fmt.Sprintf("%x", hash.Sum(nil)), nil
-}
-
-func FindFileByHash(root, targetHash string) (string, error) {
-	var found string
-
-	if err := filepath.Walk(root, func(path string, info os.FileInfo, err error) error {
-		if err != nil {
-			return err
-		}
-		if info.IsDir() {
-			return nil
-		}
-
-		f, err := os.Open(path)
-		if err != nil {
-			return nil
-		}
-		defer f.Close()
-
-		h := sha256.New()
-		if _, err := io.Copy(h, f); err != nil {
-			return nil
-		}
-		sum := hex.EncodeToString(h.Sum(nil))
-		if sum == targetHash {
-			found = path
-			return filepath.SkipDir
-		}
-		return nil
-	}); err != nil {
-		return "", err
-	}
-
-	return found, nil
-}

main.go

@@ -1,7 +1,16 @@
 package main
 
-import "github.com/mathismqn/godeez/cmd"
+import (
+	"context"
+	"os"
+	"os/signal"
+
+	"github.com/mathismqn/godeez/cmd"
+)
 
 func main() {
-	cmd.RootCmd.Execute()
+	ctx, stop := signal.NotifyContext(context.Background(), os.Interrupt)
+	defer stop()
+
+	cmd.RootCmd.ExecuteContext(ctx)
 }