initial support for playlist modifiers

supported modifiers are --playlist-start, --playlist-end, --playlist-reverse, --max-downloads

README.md

@@ -25,6 +25,11 @@ docker pull ghcr.io/marcopiovanello/yt-dlp-web-ui:latest
 
 *Keeps the project alive!* 😃
 
+## Community stuff
+Feel free to join :)
+
+[![Discord Banner](https://api.weblutions.com/discord/invite/3Sj9ZZHv/)](https://discord.gg/3Sj9ZZHv)
+
 ## Some screeshots
 ![image](https://github.com/user-attachments/assets/fc43a3fb-ecf9-449d-b5cb-5d5635020c00)
 ![image](https://github.com/user-attachments/assets/3210f6ac-0dd8-403c-b839-3c24ff7d7d00)

frontend/src/assets/i18n/ca.yaml

@@ -69,3 +69,12 @@ keys:
   noFilesFound: 'No Files Found'
   tableView: 'Table View'
   deleteSelected: 'Delete selected'
+  subscriptionsButtonLabel: 'Subscriptions'
+  subscriptionsEmptyLabel: 'No subscriptions'
+  subscriptionsURLInput: 'Channel URL'
+  subscriptionsInfo: |
+    Subscribes to a defined channel. Only the last video will be downloaded.
+    The monitor job will be scheduled/triggered by a defined cron expression (defaults to every 5 minutes if left blank).
+  cronExpressionLabel: 'Cron expression'
+  editButtonLabel: 'Edit'
+  newSubscriptionButton: New subscription

frontend/src/assets/i18n/de.yaml

@@ -71,3 +71,12 @@ keys:
   noFilesFound: 'Keine Dateien gefunden'
   tableView: 'Tabellenansicht'
   deleteSelected: 'Ausgewählte löschen'
+  subscriptionsButtonLabel: 'Subscriptions'
+  subscriptionsEmptyLabel: 'No subscriptions'
+  subscriptionsURLInput: 'Channel URL'
+  subscriptionsInfo: |
+    Subscribes to a defined channel. Only the last video will be downloaded.
+    The monitor job will be scheduled/triggered by a defined cron expression (defaults to every 5 minutes if left blank).
+  cronExpressionLabel: 'Cron expression'
+  editButtonLabel: 'Edit'
+  newSubscriptionButton: New subscription

frontend/src/assets/i18n/en_US.yaml

@@ -27,11 +27,11 @@ keys:
   customPath: Custom path
   customArgs: Enable custom yt-dlp args (great power = great responsibilities)
   customArgsInput: Custom yt-dlp arguments
-  rpcConnErr: Error while conencting to RPC server
+  rpcConnErr: Error while connecting to RPC server
   splashText: No active downloads
   archiveTitle: Archive
   clipboardAction: Copied URL to clipboard
-  playlistCheckbox: Download playlist (it will take time, after submitting you may close this window)
+  playlistCheckbox: Download playlist
   restartAppMessage: Needs a page reload to take effect
   servedFromReverseProxyCheckbox: Is behind a reverse proxy
   urlBase: URL base, for reverse proxy support (subdir), defaults to empty

frontend/src/assets/i18n/es.yaml

@@ -68,4 +68,13 @@ keys:
   deleteCookies: Delete Cookies
   noFilesFound: 'No Files Found'
   tableView: 'Table View'
-  deleteSelected: 'Delete selected'
+  deleteSelected: 'Delete selected'
+  subscriptionsButtonLabel: 'Subscriptions'
+  subscriptionsEmptyLabel: 'No subscriptions'
+  subscriptionsURLInput: 'Channel URL'
+  subscriptionsInfo: |
+    Subscribes to a defined channel. Only the last video will be downloaded.
+    The monitor job will be scheduled/triggered by a defined cron expression (defaults to every 5 minutes if left blank).
+  cronExpressionLabel: 'Cron expression'
+  editButtonLabel: 'Edit'
+  newSubscriptionButton: New subscription

frontend/src/assets/i18n/fr.yaml

@@ -72,4 +72,13 @@ keys:
   deleteCookies: Delete Cookies
   noFilesFound: 'No Files Found'
   tableView: 'Table View'
-  deleteSelected: 'Delete selected'
+  deleteSelected: 'Delete selected'
+  subscriptionsButtonLabel: 'Subscriptions'
+  subscriptionsEmptyLabel: 'No subscriptions'
+  subscriptionsURLInput: 'Channel URL'
+  subscriptionsInfo: |
+    Subscribes to a defined channel. Only the last video will be downloaded.
+    The monitor job will be scheduled/triggered by a defined cron expression (defaults to every 5 minutes if left blank).
+  cronExpressionLabel: 'Cron expression'
+  editButtonLabel: 'Edit'
+  newSubscriptionButton: New subscription

frontend/src/assets/i18n/hu.yaml

@@ -70,4 +70,13 @@ keys:
   deleteCookies: Sütik törlése
   noFilesFound: 'Nem található fájlok'
   tableView: 'Táblázatos Nézet'
-  deleteSelected: 'Kiválasztottak törlése'
+  deleteSelected: 'Kiválasztottak törlése'
+  subscriptionsButtonLabel: 'Subscriptions'
+  subscriptionsEmptyLabel: 'No subscriptions'
+  subscriptionsURLInput: 'Channel URL'
+  subscriptionsInfo: |
+    Subscribes to a defined channel. Only the last video will be downloaded.
+    The monitor job will be scheduled/triggered by a defined cron expression (defaults to every 5 minutes if left blank).
+  cronExpressionLabel: 'Cron expression'
+  editButtonLabel: 'Edit'
+  newSubscriptionButton: New subscription

frontend/src/assets/i18n/it_IT.yaml

@@ -1,8 +1,9 @@
 keys:
   urlInput: URL Video (uno per linea)
   statusTitle: Stato
-  startButton: Inizia
   statusReady: Pronto
+  selectFormatButton: Seziona formato
+  startButton: Inizia
   abortAllButton: Termina tutto
   updateBinButton: Aggiorna yt-dlp
   darkThemeButton: Tema scuro
@@ -22,51 +23,60 @@ keys:
   pathOverrideOption: Abilita sovrascrittura percorso di output
   filenameOverrideOption: Abilita sovrascrittura del nome del file di output
   autoFileExtensionOption: Aggiungi estensione automaticamente
-  customFilename: Custom filename (leave blank to use default)
+  customFilename: Nome file personalizzato (lascia vuoto per utilizzare quello predefinito)
-  customPath: Custom path
+  customPath: Percorso personalizzato
-  customArgs: Enable custom yt-dlp args (great power = great responsabilities)
+  customArgs: Abilita argomenti yt-dlp personalizzati (grande potere = grandi responsabilità)
-  customArgsInput: Custom yt-dlp arguments
+  customArgsInput: Argomenti yt-dlp personalizzati
-  rpcConnErr: Error nella connessione al server RPC
+  rpcConnErr: Errore nella connessione al server RPC
   splashText: Nessun download attivo
   archiveTitle: Archivio
   clipboardAction: URL copiato negli appunti
   playlistCheckbox: Download playlist (richiederà tempo, puoi chiudere la finestra dopo l'inoltro)
-  restartAppMessage: La finestra deve essere ricaricata perché abbia effetto
+  restartAppMessage: La finestra deve essere ricaricata affinché abbia effetto
-  servedFromReverseProxyCheckbox: Is behind a reverse proxy
+  servedFromReverseProxyCheckbox: È dietro un reverse proxy
+  urlBase: base URL, per supporto a reverse proxy (subdir), default vuoto
   newDownloadButton: Nuovo download
   homeButtonLabel: Home
-  archiveButtonLabel: Archive
+  archiveButtonLabel: Archivio
-  settingsButtonLabel: Settings
+  settingsButtonLabel: Impostazioni
-  rpcAuthenticationLabel: RPC authentication
+  rpcAuthenticationLabel: Autenticazione RPC
-  themeTogglerLabel: Theme toggler
+  themeTogglerLabel: Selettore Tema
-  loadingLabel: Loading...
+  loadingLabel: Caricamento...
   appTitle: Titolo applicazione
-  savedTemplates: Template salvati
+  savedTemplates: Modelli salvati
-  templatesEditor: Editor template
+  templatesEditor: Editor modelli
-  templatesEditorNameLabel: Nome template
+  templatesEditorNameLabel: Nome modello
-  templatesEditorContentLabel: Contentunto template
+  templatesEditorContentLabel: Contenuto del modello
   logsTitle: 'Logs'
   awaitingLogs: 'Awaiting logs...'
-  bulkDownload: 'Download files in a zip archive'
+  bulkDownload: 'Scaricare i file in un archivio zip'
-  templatesReloadInfo: To register a new template it might need a page reload.
-  livestreamURLInput: Livestream URL
-  livestreamStatusWaiting: Waiting/Wait start
-  livestreamStatusDownloading: Downloading
-  livestreamStatusCompleted: Completed
-  livestreamStatusErrored: Errored
-  livestreamStatusUnknown: Unknown
-  livestreamNoMonitoring: No livestreams monitored
-  livestreamDownloadInfo: |
-    This will monitor yet to start livestream. Each process will be executed with --wait-for-video 10.
-    If an already started livestream is provided it will be still downloaded but its progress will not be tracked.
-    Once started the livestream will be migrated to the downloads page.
-  livestreamExperimentalWarning: This feature is still experimental. Something might break!
-  accentSelect: 'Accent'
-  urlBase: base URL, per supporto a reverse proxy (subdir), default vuoto
   rpcPollingTimeTitle: Intervallo di polling RPC
   rpcPollingTimeDescription: Un intervallo più corto implica un maggior utilizzo di CPU (lato client e server)
-  generalDownloadSettings: 'General Download Settings'
+  templatesReloadInfo: Per registrare un nuovo modello potrebbe essere necessario ricaricare la pagina.
-  deleteCookies: Delete Cookies
+  livestreamURLInput: Livestream URL
-  noFilesFound: 'No Files Found'
+  livestreamStatusWaiting: Attesa inizio
-  tableView: 'Table View'
+  livestreamStatusDownloading: Downloading
-  deleteSelected: 'Delete selected'
+  livestreamStatusCompleted: Completato
+  livestreamStatusErrored: Errore
+  livestreamStatusUnknown: Sconosciuto
+  livestreamNoMonitoring: Nessun livestream monitorato
+  livestreamDownloadInfo: |
+    Questo monitorerà il livestream ancora da avviare. Ogni processo verrà eseguito con --wait-for-video 10.
+    Se viene fornito un livestream già avviato, questo verrà comunque scaricato, ma il suo progresso non verrà monitorato.
+    Una volta avviato, il livestream verrà migrato nella pagina dei download.
+  livestreamExperimentalWarning: Questa funzione è ancora sperimentale. Qualcosa potrebbe rompersi!
+  accentSelect: 'Accent'
+  generalDownloadSettings: 'Impostazioni generali di download'
+  deleteCookies: Elimina Cookies
+  noFilesFound: 'Nessun file trovato'
+  tableView: 'Vista Tabella'
+  deleteSelected: 'Elimina selezionati'
+  subscriptionsButtonLabel: 'Abbonamenti'
+  subscriptionsEmptyLabel: 'Nessuna iscrizione'
+  subscriptionsURLInput: 'URL Canale'
+  subscriptionsInfo: |
+    Iscrive a un canale definito. Verrà scaricato solo l'ultimo video.
+    Il lavoro di monitoraggio sarà programmato/attivato da un'espressione cron definita (se lasciata vuota, l'impostazione predefinita è ogni 5 minuti).
+  cronExpressionLabel: 'Espressione Cron'
+  editButtonLabel: 'Modifica'
+  newSubscriptionButton: Nuova iscrizione

frontend/src/assets/i18n/ja.yaml

@@ -69,4 +69,13 @@ keys:
   deleteCookies: Delete Cookies
   noFilesFound: 'No Files Found'
   tableView: 'Table View'
-  deleteSelected: 'Delete selected'
+  deleteSelected: 'Delete selected'
+  subscriptionsButtonLabel: 'Subscriptions'
+  subscriptionsEmptyLabel: 'No subscriptions'
+  subscriptionsURLInput: 'Channel URL'
+  subscriptionsInfo: |
+    Subscribes to a defined channel. Only the last video will be downloaded.
+    The monitor job will be scheduled/triggered by a defined cron expression (defaults to every 5 minutes if left blank).
+  cronExpressionLabel: 'Cron expression'
+  editButtonLabel: 'Edit'
+  newSubscriptionButton: New subscription

frontend/src/assets/i18n/ko.yaml

@@ -68,4 +68,13 @@ keys:
   deleteCookies: Delete Cookies
   noFilesFound: 'No Files Found'
   tableView: 'Table View'
-  deleteSelected: 'Delete selected'
+  deleteSelected: 'Delete selected'
+  subscriptionsButtonLabel: 'Subscriptions'
+  subscriptionsEmptyLabel: 'No subscriptions'
+  subscriptionsURLInput: 'Channel URL'
+  subscriptionsInfo: |
+    Subscribes to a defined channel. Only the last video will be downloaded.
+    The monitor job will be scheduled/triggered by a defined cron expression (defaults to every 5 minutes if left blank).
+  cronExpressionLabel: 'Cron expression'
+  editButtonLabel: 'Edit'
+  newSubscriptionButton: New subscription

frontend/src/assets/i18n/pl.yaml

@@ -68,4 +68,13 @@ keys:
   deleteCookies: Delete Cookies
   noFilesFound: 'No Files Found'
   tableView: 'Table View'
-  deleteSelected: 'Delete selected'
+  deleteSelected: 'Delete selected'
+  subscriptionsButtonLabel: 'Subscriptions'
+  subscriptionsEmptyLabel: 'No subscriptions'
+  subscriptionsURLInput: 'Channel URL'
+  subscriptionsInfo: |
+    Subscribes to a defined channel. Only the last video will be downloaded.
+    The monitor job will be scheduled/triggered by a defined cron expression (defaults to every 5 minutes if left blank).
+  cronExpressionLabel: 'Cron expression'
+  editButtonLabel: 'Edit'
+  newSubscriptionButton: New subscription

frontend/src/assets/i18n/pt_BR.yaml

@@ -70,4 +70,13 @@ keys:
   deleteCookies: Delete Cookies
   noFilesFound: 'No Files Found'
   tableView: 'Table View'
-  deleteSelected: 'Delete selected'
+  deleteSelected: 'Delete selected'
+  subscriptionsButtonLabel: 'Subscriptions'
+  subscriptionsEmptyLabel: 'No subscriptions'
+  subscriptionsURLInput: 'Channel URL'
+  subscriptionsInfo: |
+    Subscribes to a defined channel. Only the last video will be downloaded.
+    The monitor job will be scheduled/triggered by a defined cron expression (defaults to every 5 minutes if left blank).
+  cronExpressionLabel: 'Cron expression'
+  editButtonLabel: 'Edit'
+  newSubscriptionButton: New subscription

frontend/src/assets/i18n/ru.yaml

@@ -68,4 +68,13 @@ keys:
   deleteCookies: Delete Cookies
   noFilesFound: 'No Files Found'
   tableView: 'Table View'
-  deleteSelected: 'Delete selected'
+  deleteSelected: 'Delete selected'
+  subscriptionsButtonLabel: 'Subscriptions'
+  subscriptionsEmptyLabel: 'No subscriptions'
+  subscriptionsURLInput: 'Channel URL'
+  subscriptionsInfo: |
+    Subscribes to a defined channel. Only the last video will be downloaded.
+    The monitor job will be scheduled/triggered by a defined cron expression (defaults to every 5 minutes if left blank).
+  cronExpressionLabel: 'Cron expression'
+  editButtonLabel: 'Edit'
+  newSubscriptionButton: New subscription

frontend/src/assets/i18n/sv.yaml

@@ -70,4 +70,13 @@ keys:
   deleteCookies: Delete Cookies
   noFilesFound: 'No Files Found'
   tableView: 'Table View'
-  deleteSelected: 'Delete selected'
+  deleteSelected: 'Delete selected'
+  subscriptionsButtonLabel: 'Subscriptions'
+  subscriptionsEmptyLabel: 'No subscriptions'
+  subscriptionsURLInput: 'Channel URL'
+  subscriptionsInfo: |
+    Subscribes to a defined channel. Only the last video will be downloaded.
+    The monitor job will be scheduled/triggered by a defined cron expression (defaults to every 5 minutes if left blank).
+  cronExpressionLabel: 'Cron expression'
+  editButtonLabel: 'Edit'
+  newSubscriptionButton: New subscription

frontend/src/assets/i18n/uk.yaml

@@ -68,4 +68,13 @@ keys:
   deleteCookies: Delete Cookies
   noFilesFound: 'No Files Found'
   tableView: 'Table View'
-  deleteSelected: 'Delete selected'
+  deleteSelected: 'Delete selected'
+  subscriptionsButtonLabel: 'Subscriptions'
+  subscriptionsEmptyLabel: 'No subscriptions'
+  subscriptionsURLInput: 'Channel URL'
+  subscriptionsInfo: |
+    Subscribes to a defined channel. Only the last video will be downloaded.
+    The monitor job will be scheduled/triggered by a defined cron expression (defaults to every 5 minutes if left blank).
+  cronExpressionLabel: 'Cron expression'
+  editButtonLabel: 'Edit'
+  newSubscriptionButton: New subscription

frontend/src/assets/i18n/zh_CN.yaml

@@ -70,4 +70,13 @@ keys:
   deleteCookies: Delete Cookies
   noFilesFound: 'No Files Found'
   tableView: 'Table View'
-  deleteSelected: 'Delete selected'
+  deleteSelected: 'Delete selected'
+  subscriptionsButtonLabel: 'Subscriptions'
+  subscriptionsEmptyLabel: 'No subscriptions'
+  subscriptionsURLInput: 'Channel URL'
+  subscriptionsInfo: |
+    Subscribes to a defined channel. Only the last video will be downloaded.
+    The monitor job will be scheduled/triggered by a defined cron expression (defaults to every 5 minutes if left blank).
+  cronExpressionLabel: 'Cron expression'
+  editButtonLabel: 'Edit'
+  newSubscriptionButton: New subscription

frontend/src/components/DownloadDialog.tsx

@@ -110,7 +110,7 @@ const DownloadDialog: FC<Props> = ({ open, onClose, onDownloadStart }) => {
       if (pickedAudioFormat !== '') codes.push(pickedAudioFormat)
       if (pickedBestFormat !== '') codes.push(pickedBestFormat)
 
-      const downloadTemplate = `${customArgsState} ${cookies}`
+      const downloadTemplate = `${customArgs} ${cookies}`
         .replace(/  +/g, ' ')
         .trim()
 

server/common/types.go

@@ -0,0 +1,18 @@
+package common
+
+import "time"
+
+// Used to deser the yt-dlp -J output
+type DownloadInfo struct {
+	URL         string    `json:"url"`
+	Title       string    `json:"title"`
+	Thumbnail   string    `json:"thumbnail"`
+	Resolution  string    `json:"resolution"`
+	Size        int32     `json:"filesize_approx"`
+	VCodec      string    `json:"vcodec"`
+	ACodec      string    `json:"acodec"`
+	Extension   string    `json:"ext"`
+	OriginalURL string    `json:"original_url"`
+	FileName    string    `json:"filename"`
+	CreatedAt   time.Time `json:"created_at"`
+}

server/internal/common_types.go

@@ -1,6 +1,8 @@
 package internal
 
-import "time"
+import (
+	"github.com/marcopiovanello/yt-dlp-web-ui/v3/server/common"
+)
 
 // Used to unmarshall yt-dlp progress
 type ProgressTemplate struct {
@@ -29,29 +31,14 @@ type DownloadProgress struct {
 	ETA        float64 `json:"eta"`
 }
 
-// Used to deser the yt-dlp -J output
-type DownloadInfo struct {
-	URL         string    `json:"url"`
-	Title       string    `json:"title"`
-	Thumbnail   string    `json:"thumbnail"`
-	Resolution  string    `json:"resolution"`
-	Size        int32     `json:"filesize_approx"`
-	VCodec      string    `json:"vcodec"`
-	ACodec      string    `json:"acodec"`
-	Extension   string    `json:"ext"`
-	OriginalURL string    `json:"original_url"`
-	FileName    string    `json:"filename"`
-	CreatedAt   time.Time `json:"created_at"`
-}
-
 // struct representing the response sent to the client
 // as JSON-RPC result field
 type ProcessResponse struct {
-	Id       string           `json:"id"`
+	Id       string              `json:"id"`
-	Progress DownloadProgress `json:"progress"`
+	Progress DownloadProgress    `json:"progress"`
-	Info     DownloadInfo     `json:"info"`
+	Info     common.DownloadInfo `json:"info"`
-	Output   DownloadOutput   `json:"output"`
+	Output   DownloadOutput      `json:"output"`
-	Params   []string         `json:"params"`
+	Params   []string            `json:"params"`
 }
 
 // struct representing the current status of the memoryDB

server/internal/playlist.go

@@ -9,20 +9,18 @@ import (
 	"strings"
 	"time"
 
+	"github.com/marcopiovanello/yt-dlp-web-ui/v3/server/common"
 	"github.com/marcopiovanello/yt-dlp-web-ui/v3/server/config"
+	"github.com/marcopiovanello/yt-dlp-web-ui/v3/server/playlist"
 )
 
-type metadata struct {
-	Entries       []DownloadInfo `json:"entries"`
-	Count         int            `json:"playlist_count"`
-	PlaylistTitle string         `json:"title"`
-	Type          string         `json:"_type"`
-}
-
 func PlaylistDetect(req DownloadRequest, mq *MessageQueue, db *MemoryDB) error {
+	params := append(req.Params, "--flat-playlist", "-J")
+	urlWithParams := append([]string{req.URL}, params...)
+
 	var (
 		downloader = config.Instance().DownloaderPath
-		cmd        = exec.Command(downloader, req.URL, "--flat-playlist", "-J")
+		cmd        = exec.Command(downloader, urlWithParams...)
 	)
 
 	stdout, err := cmd.StdoutPipe()
@@ -30,7 +28,7 @@ func PlaylistDetect(req DownloadRequest, mq *MessageQueue, db *MemoryDB) error {
 		return err
 	}
 
-	var m metadata
+	var m playlist.Metadata
 
 	if err := cmd.Start(); err != nil {
 		return err
@@ -53,12 +51,20 @@ func PlaylistDetect(req DownloadRequest, mq *MessageQueue, db *MemoryDB) error {
 	}
 
 	if m.Type == "playlist" {
-		entries := slices.CompactFunc(slices.Compact(m.Entries), func(a DownloadInfo, b DownloadInfo) bool {
+		entries := slices.CompactFunc(slices.Compact(m.Entries), func(a common.DownloadInfo, b common.DownloadInfo) bool {
 			return a.URL == b.URL
 		})
 
+		entries = slices.DeleteFunc(entries, func(e common.DownloadInfo) bool {
+			return strings.Contains(e.URL, "list=")
+		})
+
 		slog.Info("playlist detected", slog.String("url", req.URL), slog.Int("count", len(entries)))
 
+		if err := playlist.ApplyModifiers(&entries, req.Params); err != nil {
+			return err
+		}
+
 		for i, meta := range entries {
 			// detect playlist title from metadata since each playlist entry will be
 			// treated as an individual download
@@ -87,6 +93,8 @@ func PlaylistDetect(req DownloadRequest, mq *MessageQueue, db *MemoryDB) error {
 			db.Set(proc)
 			mq.Publish(proc)
 		}
+
+		return nil
 	}
 
 	proc := &Process{

server/internal/process.go

@@ -19,6 +19,7 @@ import (
 	"time"
 
 	"github.com/marcopiovanello/yt-dlp-web-ui/v3/server/archiver"
+	"github.com/marcopiovanello/yt-dlp-web-ui/v3/server/common"
 	"github.com/marcopiovanello/yt-dlp-web-ui/v3/server/config"
 )
 
@@ -50,7 +51,7 @@ type Process struct {
 	Livestream bool
 	AutoRemove bool
 	Params     []string
-	Info       DownloadInfo
+	Info       common.DownloadInfo
 	Progress   DownloadProgress
 	Output     DownloadOutput
 	proc       *os.Process
@@ -302,7 +303,7 @@ func (p *Process) GetFileName(o *DownloadOutput) error {
 
 func (p *Process) SetPending() {
 	// Since video's title isn't available yet, fill in with the URL.
-	p.Info = DownloadInfo{
+	p.Info = common.DownloadInfo{
 		URL:       p.Url,
 		Title:     p.Url,
 		CreatedAt: time.Now(),
@@ -334,7 +335,7 @@ func (p *Process) SetMetadata() error {
 		return err
 	}
 
-	info := DownloadInfo{
+	info := common.DownloadInfo{
 		URL:       p.Url,
 		CreatedAt: time.Now(),
 	}

server/playlist/modifiers.go

@@ -0,0 +1,86 @@
+package playlist
+
+import (
+	"slices"
+	"strconv"
+
+	"github.com/marcopiovanello/yt-dlp-web-ui/v3/server/common"
+)
+
+/*
+	Applicable modifiers
+
+				full									|		   short		  |					description
+	---------------------------------------------------------------------------------
+	--playlist-start NUMBER     |    -I NUMBER:	  |	  discard first N entries
+	--playlist-end NUMBER       |    -I :NUMBER   |   discard last N entries
+	--playlist-reverse          |    -I ::-1			|   self explanatory
+	--max-downloads NUMBER      |                 |   stops after N completed downloads
+*/
+
+func ApplyModifiers(entries *[]common.DownloadInfo, args []string) error {
+	for i, modifier := range args {
+		switch modifier {
+		case "--playlist-start":
+			return playlistStart(i, modifier, args, entries)
+
+		case "--playlist-end":
+			return playlistEnd(i, modifier, args, entries)
+
+		case "--max-downloads":
+			return maxDownloads(i, modifier, args, entries)
+
+		case "--playlist-reverse":
+			slices.Reverse(*entries)
+			return nil
+		}
+	}
+	return nil
+}
+
+func playlistStart(i int, modifier string, args []string, entries *[]common.DownloadInfo) error {
+	if !guard(i, len(modifier)) {
+		return nil
+	}
+
+	n, err := strconv.Atoi(args[i+1])
+	if err != nil {
+		return err
+	}
+
+	*entries = (*entries)[n:]
+
+	return nil
+}
+
+func playlistEnd(i int, modifier string, args []string, entries *[]common.DownloadInfo) error {
+	if !guard(i, len(modifier)) {
+		return nil
+	}
+
+	n, err := strconv.Atoi(args[i+1])
+	if err != nil {
+		return err
+	}
+
+	*entries = (*entries)[:n]
+
+	return nil
+}
+
+func maxDownloads(i int, modifier string, args []string, entries *[]common.DownloadInfo) error {
+	if !guard(i, len(modifier)) {
+		return nil
+	}
+
+	n, err := strconv.Atoi(args[i+1])
+	if err != nil {
+		return err
+	}
+
+	*entries = (*entries)[0:n]
+
+	return nil
+}
+
+func guard(i, len int) bool { return i+1 < len-1 }

server/playlist/types.go

@@ -0,0 +1,10 @@
+package playlist
+
+import "github.com/marcopiovanello/yt-dlp-web-ui/v3/server/common"
+
+type Metadata struct {
+	Entries       []common.DownloadInfo `json:"entries"`
+	Count         int                   `json:"playlist_count"`
+	PlaylistTitle string                `json:"title"`
+	Type          string                `json:"_type"`
+}