vovaaa312/viby

Purpose and Runtime

Viby is a single-module Android offline music player. It downloads YouTube video/playlist audio entirely on-device, stores MP3s in app-scoped external storage, and plays the local library in the background. The APK bundles a Python runtime, yt-dlp, and FFmpeg; playback uses Android Media3/ExoPlayer and the platform equalizer. Build/runtime definition: app/build.gradle, app/src/main/AndroidManifest.xml.

Application and UI Entry Points

VibyApp is the application-level bootstrap. MainActivity is the primary library/player host, with player and queue presented as fragments. Dedicated activities isolate download intake, equalizer controls, and YouTube authentication/playlist selection.

• app/src/main/java/com/example/viby/VibyApp.java

• app/src/main/java/com/example/viby/ui/MainActivity.java

• app/src/main/java/com/example/viby/ui/PlayerFragment.java

• app/src/main/java/com/example/viby/ui/DownloadActivity.java

Persistent Library Model

Room-style local persistence represents downloaded tracks, playlist metadata/source links, and resumable/pending download state. This database is the boundary between UI/library management and background work; downloaded media itself lives under Android/data/com.example.viby/files/Music/<playlist>/.

• app/src/main/java/com/example/viby/data/VibyDatabase.java

• app/src/main/java/com/example/viby/data/Track.java

• app/src/main/java/com/example/viby/data/PlaylistInfo.java

• app/src/main/java/com/example/viby/data/PendingDownload.java

Download and Extraction Pipeline

A user supplies or shares a YouTube URL through the download/login/playlist UI. Download jobs coordinate per-track or per-playlist progress and persistent pending state. The background download service invokes the embedded extraction stack, produces tagged MP3s with cover art, and updates the local library. YouTube access/authentication and cookie handling are separate boundaries from local playback.

• app/src/main/java/com/example/viby/download/DownloadService.java

• app/src/main/java/com/example/viby/download/DownloadJob.java

• app/src/main/java/com/example/viby/ui/YoutubeLoginActivity.java

• app/src/main/java/com/example/viby/util/YtCookies.java

Playback and Audio Effects

PlaybackService owns long-lived background audio, media notification/session behavior, queue progression, shuffle/repeat, and the Media3/ExoPlayer lifecycle. UI observes/controls it through PlayerViewModel; it should not directly own playback resources. Equalizer effects attach at the Android audio-session boundary and expose preset definitions separately.

• app/src/main/java/com/example/viby/playback/PlaybackService.java

• app/src/main/java/com/example/viby/ui/PlayerViewModel.java

• app/src/main/java/com/example/viby/playback/EqFx.java

• app/src/main/java/com/example/viby/playback/EqPresets.java

Library, Queue, and Presentation Flow

Library screens render persisted tracks and playlists through adapters; selection/context actions change queue, playlist membership, or files/database records. QueueFragment represents the playback queue, while PlayerFragment provides transport controls and waveform seeking. Waveform generation/extraction is a local media-processing concern, not a download-service responsibility.

• app/src/main/java/com/example/viby/ui/QueueFragment.java

• app/src/main/java/com/example/viby/ui/TracksAdapter.java

• app/src/main/java/com/example/viby/ui/PlaylistsAdapter.java

• app/src/main/java/com/example/viby/util/WaveformExtractor.java

Key Boundaries and External Dependencies

The app has no server: YouTube is the external content source, while yt-dlp/FFmpeg are bundled on-device execution dependencies. Android app-scoped external storage is the media boundary, mediated by storage utilities. UI resources provide the Android presentation layer and localization/theme assets.

• app/src/main/java/com/example/viby/util/StorageHelper.java

• app/src/main/res/layout/activity_main.xml

• app/src/main/res/layout/fragment_player.xml