feat(player): stream audio by default, add [audio] config for cookies and downloads

Long tracks (15 min to 1 hour+) didnt playbecause every song was fully
downloaded with yt-dlp into the cache before mpv was started.

Resolve the direct media URL with yt-dlp -g and hand it to mpv, so
playback starts within a couple of seconds. Cached files are still
used when present.

Add an [audio] section to config.toml:
- download: download songs to the cache before playing (default false,
  i.e. stream). Prefetch of the next track only runs in this mode.
- download_max_minutes: in download mode, songs longer than this (or of
  unknown length) are still streamed so 0 means no limit. default is le 15.
- cookies_from_browser: passed to yt-dlp as --cookies-from-browser for
  playback, for when YouTube asks to sign in or blocks a song.

README.md

@@ -170,8 +170,15 @@ accent = "cyan"       # a color name or a hex value like "#FF8800"
 
 [discord]
 client_id = ""        # change this for Discord RPC to work in Drift
+
+[audio]
+download = false              # false: stream songs; true: download to the cache first
+download_max_minutes = 15     # with download = true, longer songs are still streamed (0 = no limit)
+cookies_from_browser = ""     # e.g. "firefox" or "chrome"; passed to yt-dlp when YouTube blocks playback
 ```
 
+By default Drift streams songs, so playback starts right away even for hour long tracks. Set `download = true` to cache songs on disk first (this also prefetches the next song). If YouTube asks you to sign in or playback fails, set `cookies_from_browser` to the browser where youre logged into YouTube. If you alr have a `config.toml`, add the `[audio]` section by hand, since Drift never rewrites it.
+
 Set `DRIFT_CONFIG_DIR` or `DRIFT_STATE_DIR` to change where Drift keeps its config, playlists and session.
 
 ## Contributing

src/app.rs

@@ -7,7 +7,7 @@ use ratatui::crossterm::event::{KeyCode, KeyEvent, KeyEventKind, KeyModifiers};
 use ratatui::widgets::TableState;
 
 use crate::command::{self, Amount, Command, COMMAND_NAMES};
-use crate::config::{self, Config};
+use crate::config::{self, Audio, Config};
 use crate::lyrics::{self, Lyrics};
 use crate::model::{split_artists, Collection, RepeatMode, Track};
 use crate::discord::Discord;
@@ -46,6 +46,10 @@ pub enum AppEvent {
         id: String,
         result: Result<std::path::PathBuf, String>,
     },
+    Stream {
+        id: String,
+        result: Result<String, String>,
+    },
 }
 
 const FIRST_PAGE: usize = 20;
@@ -215,6 +219,8 @@ pub struct App {
     fail_streak: u8,
     want: Option<String>,
     fetching: Option<String>,
+    resolving: Option<String>,
+    audio: Audio,
     result_cursor: Option<usize>,
     buffered: Vec<Track>,
     next_page: Option<String>,
@@ -315,6 +321,8 @@ impl App {
             fail_streak: 0,
             want: None,
             fetching: None,
+            resolving: None,
+            audio: cfg.audio.clone(),
             result_cursor: None,
             buffered: Vec::new(),
             next_page: None,
@@ -1625,6 +1633,7 @@ impl App {
                 };
             }
             AppEvent::Audio { id, result } => self.on_audio(id, result),
+            AppEvent::Stream { id, result } => self.on_stream(id, result),
             AppEvent::Player(generation, pe) => {
                 if generation == self.player_gen {
                     self.on_player(pe);
@@ -1754,17 +1763,53 @@ impl App {
         self.fetching = Some(id.to_string());
         let tx = self.tx.clone();
         let id = id.to_string();
+        let audio = self.audio.clone();
         std::thread::spawn(move || {
-            let result = player::fetch_audio(&id);
+            let result = player::fetch_audio(&id, &audio);
             let _ = tx.send(AppEvent::Audio { id, result });
         });
     }
 
-    fn load_track(&mut self, id: &str) {
+    fn load_track(&mut self, id: &str, duration: Option<u32>) {
         self.want = Some(id.to_string());
         match player::cached_audio(id) {
             Some(path) => self.on_audio(id.to_string(), Ok(path)),
-            None => self.fetch_audio(id),
+            None if self.audio.should_download(duration) => self.fetch_audio(id),
+            None => self.resolve_stream(id),
+        }
+    }
+
+    /* Start playing from the network right away; no full download first. */
+    fn resolve_stream(&mut self, id: &str) {
+        if self.resolving.as_deref() == Some(id) {
+            return;
+        }
+        self.resolving = Some(id.to_string());
+        let tx = self.tx.clone();
+        let id = id.to_string();
+        let audio = self.audio.clone();
+        std::thread::spawn(move || {
+            let result = player::resolve_stream(&id, &audio);
+            let _ = tx.send(AppEvent::Stream { id, result });
+        });
+    }
+
+    fn on_stream(&mut self, id: String, result: Result<String, String>) {
+        if self.resolving.as_deref() == Some(id.as_str()) {
+            self.resolving = None;
+        }
+        if self.want.as_deref() != Some(id.as_str()) {
+            return;
+        }
+        self.want = None;
+        match result {
+            Ok(url) => {
+                if let Err(e) = self.with_player(|p| p.load(&url)) {
+                    self.play_state = PlayState::Stopped;
+                    self.error(format!("Playback failed: {e:#}"));
+                }
+            }
+            Err(msg) => self.on_player(PlayerEvent::LoadError(msg)),
         }
     }
 
@@ -1795,6 +1840,10 @@ impl App {
         let Some(next) = self.current.and_then(|c| self.queue.get(c + 1)) else {
             return;
         };
+        /* streamed tracks (the default, or too long to download) aren't prefetched */
+        if !self.audio.should_download(next.duration) {
+            return;
+        }
         let id = next.id.clone();
         if player::cached_audio(&id).is_none() {
             self.fetch_audio(&id);
@@ -1822,7 +1871,7 @@ impl App {
         };
         self.duration = track.duration.map_or(0.0, f64::from);
         self.info(format!("♪ {}", track.label()));
-        self.load_track(&track.id);
+        self.load_track(&track.id, track.duration);
     }
 
     fn play_default(&mut self) {
@@ -1914,7 +1963,7 @@ impl App {
         self.position = 0.0;
         self.duration = track.duration.map_or(0.0, f64::from);
         self.info(format!("♪ {}", track.label()));
-        self.load_track(&track.id);
+        self.load_track(&track.id, track.duration);
     }
 
     fn set_pause(&mut self, pause: bool) {

src/config.rs

@@ -80,6 +80,45 @@ pub struct Discord {
     pub client_id: String,
 }
 
+#[derive(Debug, Clone, Deserialize)]
+#[serde(default)]
+pub struct Audio {
+    pub download: bool,
+    pub download_max_minutes: u32,
+    pub cookies_from_browser: String,
+}
+
+impl Default for Audio {
+    fn default() -> Self {
+        Audio {
+            download: false,
+            download_max_minutes: 15,
+            cookies_from_browser: String::new(),
+        }
+    }
+}
+
+impl Audio {
+    /// Browser name for yt-dlp's --cookies-from-browser, if one is set.
+    pub fn cookies(&self) -> Option<&str> {
+        let c = self.cookies_from_browser.trim();
+        (!c.is_empty()).then_some(c)
+    }
+
+    /// Whether a track should be downloaded to the cache before playing,
+    /// as opposed to streamed. Unknown lengths are streamed when a limit is set.
+    pub fn should_download(&self, duration: Option<u32>) -> bool {
+        if !self.download {
+            return false;
+        }
+        match (self.download_max_minutes, duration) {
+            (0, _) => true,
+            (max, Some(d)) => d <= max.saturating_mul(60),
+            (_, None) => false,
+        }
+    }
+}
+
 fn default_accent() -> Color {
     Color::Cyan
 }
@@ -104,6 +143,7 @@ pub struct Config {
     pub artist: Artist,
     pub ui: Ui,
     pub discord: Discord,
+    pub audio: Audio,
 }
 
 impl Config {
@@ -111,7 +151,7 @@ impl Config {
         Ok(Store::dir()?.join("config.toml"))
     }
 
-    pub fn render(p: &Playback, a: &Artist, u: &Ui, d: &Discord) -> String {
+    pub fn render(p: &Playback, a: &Artist, u: &Ui, d: &Discord, au: &Audio) -> String {
         let accent = match u.accent {
             Color::Reset => "reset",
             Color::Black => "black",
@@ -163,6 +203,19 @@ accent = \"{accent}\"
 # https://discord.com/developers/applications (its name is shown after
 # \"Listening to\") and paste its Application ID here. Empty means off.
 client_id = \"{client_id}\"
+
+[audio]
+# false: stream songs straight from YouTube (starts playing right away).
+# true:  download songs to the cache first, then play (and prefetch the next one).
+download = {download}
+# With download = true, songs longer than this many minutes are still streamed
+# instead of downloaded. 0 means download everything, however long.
+download_max_minutes = {dl_max}
+# Use your browser's cookies with yt-dlp when YouTube refuses to play something
+# (\"Sign in to confirm you're not a bot\", age-restricted songs, ...).
+# Examples: \"firefox\", \"chrome\", \"chromium\", \"brave\", \"edge\",
+# \"firefox:my-profile\". Empty means off. Close the browser if reading fails.
+cookies_from_browser = \"{cookies}\"
 ",
             volume = p.volume,
             shuffle = p.shuffle,
@@ -174,6 +227,9 @@ client_id = \"{client_id}\"
             popular = a.popular_first,
             accent = accent,
             client_id = d.client_id,
+            download = au.download,
+            dl_max = au.download_max_minutes,
+            cookies = au.cookies_from_browser.replace(['\\', '"'], ""),
         )
     }
 
@@ -188,7 +244,7 @@ client_id = \"{client_id}\"
         let text = match fs::read_to_string(&path) {
             Ok(t) => t,
             Err(e) if e.kind() == std::io::ErrorKind::NotFound => {
-                let _ = Self::write(&Self::render(&Playback::default(), &Artist::default(), &Ui::default(), &Discord::default()));
+                let _ = Self::write(&Self::render(&Playback::default(), &Artist::default(), &Ui::default(), &Discord::default(), &Audio::default()));
                 return (Config::default(), None);
             }
             Err(e) => {
@@ -267,7 +323,7 @@ pub fn migrate_legacy() {
             let _ = Session::write(&s);
         }
     }
-    let _ = Config::write(&Config::render(&p, &Artist::default(), &Ui::default(), &Discord::default()));
+    let _ = Config::write(&Config::render(&p, &Artist::default(), &Ui::default(), &Discord::default(), &Audio::default()));
 }
 
 #[cfg(test)]
@@ -276,7 +332,7 @@ mod tests {
 
     #[test]
     fn default_file_parses_back() {
-        let text = Config::render(&Playback::default(), &Artist::default(), &Ui::default(), &Discord::default());
+        let text = Config::render(&Playback::default(), &Artist::default(), &Ui::default(), &Discord::default(), &Audio::default());
         let c: Config = toml::from_str(&text).unwrap();
         let d = Playback::default();
         assert_eq!(c.playback.volume, d.volume);
@@ -343,8 +399,42 @@ mod tests {
 
         // Roundtrip: render then parse
         let u = Ui { accent: Color::Blue };
-        let text = Config::render(&Playback::default(), &Artist::default(), &u, &Discord::default());
+        let text = Config::render(&Playback::default(), &Artist::default(), &u, &Discord::default(), &Audio::default());
         let c: Config = toml::from_str(&text).unwrap();
         assert_eq!(c.ui.accent, Color::Blue);
     }
+
+    #[test]
+    fn audio_section() {
+        let c: Config = toml::from_str("").unwrap();
+        assert!(!c.audio.download);
+        assert_eq!(c.audio.cookies(), None);
+        let c: Config = toml::from_str(
+            "[audio]\ndownload = true\ndownload_max_minutes = 10\ncookies_from_browser = \" firefox \"",
+        )
+        .unwrap();
+        assert_eq!(c.audio.cookies(), Some("firefox"));
+        assert!(c.audio.should_download(Some(600)));
+        assert!(!c.audio.should_download(Some(601)));
+        assert!(!c.audio.should_download(None));
+        let mut a = c.audio.clone();
+        a.download_max_minutes = 0;
+        assert!(a.should_download(Some(10_000)));
+        a.download = false;
+        assert!(!a.should_download(Some(1)));
+    }
+
+    #[test]
+    fn audio_roundtrip() {
+        let a = Audio {
+            download: true,
+            download_max_minutes: 30,
+            cookies_from_browser: "chrome".into(),
+        };
+        let text = Config::render(&Playback::default(), &Artist::default(), &Ui::default(), &Discord::default(), &a);
+        let c: Config = toml::from_str(&text).unwrap();
+        assert!(c.audio.download);
+        assert_eq!(c.audio.download_max_minutes, 30);
+        assert_eq!(c.audio.cookies(), Some("chrome"));
+    }
 }

src/player.rs

@@ -6,6 +6,8 @@ use std::time::{Duration, Instant};
 use anyhow::{anyhow, bail, Result};
 use serde_json::{json, Value};
 
+use crate::config::Audio;
+
 /// Platform-specific transport for mpv's JSON IPC.
 /// Unix: a Unix domain socket. Windows: a named pipe (`\\.\pipe\...`).
 #[cfg(unix)]
@@ -311,6 +313,15 @@ impl Drop for Player {
 
 const KEEP_FILES: usize = 40;
 
+/// Base yt-dlp command with the user's cookie setting applied.
+fn ytdlp(audio: &Audio) -> Command {
+    let mut cmd = Command::new("yt-dlp");
+    if let Some(browser) = audio.cookies() {
+        cmd.arg("--cookies-from-browser").arg(browser);
+    }
+    cmd
+}
+
 fn audio_dir() -> PathBuf {
     dirs::cache_dir()
         .unwrap_or_else(std::env::temp_dir)
@@ -326,13 +337,13 @@ pub fn cached_audio(id: &str) -> Option<PathBuf> {
         .find(|p| p.file_stem().and_then(|s| s.to_str()) == Some(id))
 }
 
-pub fn fetch_audio(id: &str) -> Result<PathBuf, String> {
+pub fn fetch_audio(id: &str, audio: &Audio) -> Result<PathBuf, String> {
     if let Some(path) = cached_audio(id) {
         return Ok(path);
     }
     let dir = audio_dir();
     std::fs::create_dir_all(&dir).map_err(|e| format!("can't create {}: {e}", dir.display()))?;
-    let mut cmd = Command::new("yt-dlp");
+    let mut cmd = ytdlp(audio);
     cmd.args(["-f", "bestaudio/best", "--no-playlist", "--no-warnings", "--no-progress", "--no-mtime"])
         .arg("-P")
         .arg(&dir)
@@ -357,6 +368,35 @@ pub fn fetch_audio(id: &str) -> Result<PathBuf, String> {
         .unwrap_or_else(|| "yt-dlp downloaded nothing".into()))
 }
 
+/// Ask yt-dlp for the direct media URL so mpv can start playing right away
+/// instead of waiting for the whole file to download.
+pub fn resolve_stream(id: &str, audio: &Audio) -> Result<String, String> {
+    let mut cmd = ytdlp(audio);
+    cmd.args(["-f", "bestaudio/best", "--no-playlist", "--no-warnings", "-g"])
+        .arg(format!("https://music.youtube.com/watch?v={id}"))
+        .stdin(Stdio::null());
+    crate::sys::no_window(&mut cmd);
+    let out = cmd
+        .output()
+        .map_err(|e| format!("could not run yt-dlp ({e}); is it installed and on PATH?"))?;
+    let stdout = String::from_utf8_lossy(&out.stdout);
+    if let Some(url) = stdout
+        .lines()
+        .map(str::trim)
+        .find(|l| l.starts_with("http"))
+        .filter(|_| out.status.success())
+    {
+        return Ok(url.to_string());
+    }
+    let stderr = String::from_utf8_lossy(&out.stderr);
+    Err(stderr
+        .lines()
+        .rev()
+        .find_map(|l| l.strip_prefix("ERROR: "))
+        .map(ytdl_reason)
+        .unwrap_or_else(|| "yt-dlp returned no stream URL".into()))
+}
+
 fn prune(dir: &std::path::Path) {
     let Ok(entries) = std::fs::read_dir(dir) else {
         return;