StemRoller: desktop stem separator, Android stems player, and server daemons

- stemroller/: PySide6/QML desktop app and player for separating music into stems
- android/: Plex music player that plays per-stem mixes, with Android Auto support,
  a graphic + parametric (Equalizer APO-style) EQ, and offline downloads
- server/: stemserve (serves stems to the app) and stemd (separates the library on
  the server's GPU, with "Stem Now" priority requests)

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

stemroller/player/app.py

@@ -0,0 +1,136 @@
+"""StemRoller Player: the Plex library and its stems, in a workbook."""
+
+import argparse
+import os
+import signal
+import sys
+
+HERE = os.path.dirname(os.path.abspath(__file__))
+
+
+def main():
+    os.environ.setdefault("QT_QUICK_CONTROLS_STYLE", "Basic")
+    os.environ.setdefault("QT_QPA_PLATFORM", "wayland;xcb")
+    os.environ.setdefault("QSG_RENDER_LOOP", "threaded")
+    ap = argparse.ArgumentParser(prog="stemroller-player")
+    ap.add_argument("--screenshot", action="append", default=[], metavar="PNG@SECONDS",
+                    help="grab the window to PNG after N seconds (repeatable; for headless checks)")
+    ap.add_argument("--quit-after", type=float, default=0, metavar="SECONDS")
+    ap.add_argument("--size", default="", metavar="WxH")
+    ap.add_argument("--no-mpris", action="store_true")
+    ap.add_argument("--eval", action="append", default=[], metavar="JS@SECONDS",
+                    help="run a JavaScript snippet against the window after N seconds (dev)")
+    args = ap.parse_args()
+
+    from PySide6.QtCore import QTimer, QUrl
+    from PySide6.QtGui import QFontDatabase, QGuiApplication, QIcon, QSurfaceFormat
+    from PySide6.QtQml import QQmlApplicationEngine
+
+    fmt = QSurfaceFormat.defaultFormat()
+    fmt.setSwapInterval(1)
+    QSurfaceFormat.setDefaultFormat(fmt)
+
+    app = QGuiApplication(sys.argv)
+    app.setApplicationName("StemRoller Player")
+    app.setOrganizationName("stemroller")
+    app.setDesktopFileName("stemroller-player")
+    app.setWindowIcon(QIcon(os.path.join(HERE, "assets", "stemroller-player.svg")))
+    for d in (os.path.join(HERE, "assets", "fonts"), os.path.join(HERE, "..", "assets", "fonts")):
+        if os.path.isdir(d):
+            for f in sorted(os.listdir(d)):
+                if f.endswith((".ttf", ".otf")):
+                    QFontDatabase.addApplicationFont(os.path.join(d, f))
+    families = set(QFontDatabase.families())
+    # Excel: Segoe UI for the chrome, Calibri (or its metric twin Carlito) in the cells.
+    ui_font = next((f for f in ("Segoe UI", "Selawik", "Inter") if f in families), "sans-serif")
+    cell_font = next((f for f in ("Aptos", "Calibri", "Carlito") if f in families), ui_font)
+
+    from . import config
+    from .engine import PlayerEngine
+    from .icons import IconProvider
+    from .library import Library
+    from .player import Player
+    from .plex import Plex
+    from .stems import StemServer
+
+    cfg = config.load()
+    plex = Plex(cfg)
+    stems = StemServer(cfg, config.CACHE_DIR)
+    engine = PlayerEngine()
+    library = Library(cfg, plex, stems)
+    player = Player(cfg, plex, stems, engine)
+    library.player = player
+    player.library = library
+    library.update_queue()
+
+    qml = QQmlApplicationEngine()
+    qml.addImageProvider("icon", IconProvider())
+    qml.addImportPath(os.path.join(HERE, "qml"))
+    ctx = qml.rootContext()
+    ctx.setContextProperty("library", library)
+    ctx.setContextProperty("sheetModel", library.model)
+    ctx.setContextProperty("player", player)
+    ctx.setContextProperty("engine", engine)
+    settings = _Settings(cfg)
+    ctx.setContextProperty("settings", settings)
+    ctx.setContextProperty("uiFont", ui_font)
+    ctx.setContextProperty("cellFont", cell_font)
+    qml.load(QUrl.fromLocalFile(os.path.join(HERE, "qml", "StemPlayer", "Main.qml")))
+    if not qml.rootObjects():
+        print("failed to load QML", file=sys.stderr)
+        return 1
+    window = qml.rootObjects()[0]
+    if args.size:
+        w, h = (int(v) for v in args.size.split("x"))
+        window.resize(w, h)
+
+    if not args.no_mpris:
+        from .mpris import Mpris
+        mpris = Mpris(player, engine, lambda: (window.show(), window.raise_(), window.requestActivate()), app.quit)
+        window.setProperty("mprisOk", mpris.ok)
+
+    for e in args.eval:
+        code, _, after = e.rpartition("@")
+        QTimer.singleShot(int(float(after) * 1000), lambda code=code: window.setProperty("devEval", code))
+    for shot in args.screenshot:
+        path, _, after = shot.rpartition("@")
+        QTimer.singleShot(int(float(after) * 1000),
+                          lambda path=path: (window.grabWindow().save(path), print("screenshot saved", path, flush=True)))
+    if args.quit_after:
+        QTimer.singleShot(int(args.quit_after * 1000), app.quit)
+
+    signal.signal(signal.SIGINT, lambda *_: app.quit())
+    keepalive = QTimer()
+    keepalive.start(500)
+    keepalive.timeout.connect(lambda: None)
+
+    def shutdown():
+        player.shutdown()
+        engine.shutdown()
+        config.save(cfg)
+    app.aboutToQuit.connect(shutdown)
+    rc = app.exec()
+    del qml
+    return rc
+
+
+def _Settings(cfg):
+    """Editable settings for File → Options."""
+    from PySide6.QtCore import QObject, Slot
+
+    from . import config
+
+    class Settings(QObject):
+        @Slot(str, result="QVariant")
+        def get(self, key):
+            return cfg.get(key)
+
+        @Slot(str, "QVariant")
+        def set(self, key, value):
+            cfg[key] = value
+            config.save(cfg)
+    return Settings()
+
+
+if __name__ == "__main__":
+    sys.exit(main())