🎵 MacNowPlaying

A macOS companion for whatever you're playing. It reads the system's now-playing state (track, artist, live position) from MediaRemote and builds two features on it:

• 🎤 Synced-lyrics overlay: a transparent, click-through karaoke overlay at the bottom of the screen. The current line is bright and sharp, neighbours dim and recede, and lines spring upward in time with the song. Hover to make it opaque.
• 💬 Discord Rich Presence: puts the current track on your Discord profile with album art and a live progress bar, for real music only (Spotify, YouTube Music, Telegram).

Lyrics come from LRCLIB (free, no API key). A menubar item shows the current track and toggles either feature.

Run

swift run        # builds and launches the overlay (no Dock icon)
swift test       # run the unit tests

Play something in YouTube Music / Apple Music / etc. and the lyrics appear. Quit from the terminal with Ctrl-C.

Build a release app

./scripts/build-app.sh   # → MacNowPlaying.app (optimised, ad-hoc signed)
open MacNowPlaying.app

./scripts/install.sh     # build + copy to /Applications; then launch via Spotlight,
                         # `open -a MacNowPlaying`, or add as a Login Item to auto-start

Produces a double-clickable MacNowPlaying.app (LSUIElement, so no Dock icon). It's ad-hoc signed for local use — for distribution to other Macs you'd sign with a Developer ID and notarise. Quit it from the menubar status item (the music note icon), which also shows the current track and a "Show Overlay" toggle.

Project layout

File	Role
main.swift	App bootstrap; transparent borderless floating NSWindow, hover polling
NowPlaying.swift	The now-playing engine: MediaRemote osascript bridge → NowPlaying snapshot
Lyrics.swift	LRCLIB fetch + [mm:ss.xx] LRC parser (lyrics feature)
Artwork.swift	Cover-art resolver via curl: iTunes Search API, then YouTube-thumbnail fallback (Discord feature)
PlayerModel.swift	Polls now-playing, fetches lyrics, tracks current line (interpolated)
LyricsView.swift	The SwiftUI karaoke view (blur/opacity gradient + spring scroll)
MenuBar.swift	Menubar status item: now-playing readout, overlay + Discord toggles, Quit
DiscordRPC.swift	Discord Rich Presence: dependency-free local-IPC client (Discord feature)

Implementation notes

A few non-obvious things (see CLAUDE.md for the full reasoning):

• MediaRemote needs osascript: on macOS 15.4+ it only serves now-playing data to Apple-signed callers, so the app reads it through an osascript bridge.
• curl, not URLSession: URLSession stalls ~8s under this app's run loop, so the lyrics and artwork lookups shell out to curl.
• Discord presence is gated to real music sources (Spotify, YouTube Music, Telegram) and shows album art resolved from iTunes (with a YouTube-thumbnail fallback). The source badge needs assets uploaded to the Discord app's Art Assets.

Debug commands: --now (current track), --probe "Artist" "Title" <dur> (lyrics lookup), --discord (test presence), --art "Artist" "Title" (cover resolver).

Next steps

• Reposition/drag, pick alternate LRCLIB version, word-level highlighting, Genius plain-text fallback.

License

MIT.