hms-mediaengine/hms_app/engine.py

"""MediaEngine: GStreamer-Compositor mit dynamischen Layern (Video + Bild).

Layer lassen sich zur Laufzeit hinzufuegen/entfernen/verschieben. Jeder
Layer hat: Quelle (Bibliotheksdatei), Alpha, Position (x/y), Groesse
(width/height), Z-Order. Die Pipeline wird bei Struktur-Aenderungen neu
gebaut, Parameter gehen nicht verloren.
"""

from __future__ import annotations

import threading
import time

import gi
gi.require_version("Gst", "1.0")
from gi.repository import Gst

Gst.init(None)


class Layer:
    """Ein aktiver Layer im Compositor."""

    def __init__(self, layer_id: int, name: str, kind: str):
        self.id = layer_id
        self.name = name
        self.kind = kind  # video | image
        self.alpha = 1.0
        self.x = 0
        self.y = 0
        self.width = 320
        self.height = 180
        self.z = 0

    def to_dict(self) -> dict:
        return {"id": self.id, "name": self.name, "kind": self.kind,
                "alpha": round(self.alpha, 3), "x": self.x, "y": self.y,
                "width": self.width, "height": self.height, "z": self.z,
                "effective": None}


class MediaEngine:
    """Compositor-Pipeline + Steuerung. Thread-sicher ueber Lock."""

    def __init__(self, settings: dict, library):
        self.settings = settings
        self.library = library
        self.pipeline = None
        self.current_jpeg = b""
        self.frame_count = 0
        self.running = False
        self.last_error: str | None = None

        self.layers: list[Layer] = []
        self._next_id = 1

        self.master = 1.0
        self.blackout = False
        self.playing = True

        self.dmx_stats = {"packets": 0, "accepted": 0, "seq_errors": 0,
                          "last_universe": None, "last_seq": None,
                          "last_time": None}
        self._lock = threading.RLock()
        self._monitor: threading.Thread | None = None

    # ---------------- Pipeline ----------------

    def _layer_source(self, layer: Layer, path: str) -> str:
        uri = f"file://{path}"
        if layer.kind == "video":
            caps = (f"video/x-raw,width={layer.width},"
                    f"height={layer.height},format=BGRA")
            return (f"uridecodebin uri={uri} ! queue ! videoconvert ! "
                    f"videoscale ! {caps} ! mix.sink_{layer.id}")
        # Bild: imagefreeze + EIN kombinierter Caps-Filter
        # (zwei Caps-Filter in Serie lassen gst-parse fehlschlagen)
        caps = (f"video/x-raw,width={layer.width},"
                f"height={layer.height},format=BGRA,framerate=15/1")
        return (f"uridecodebin uri={uri} ! imagefreeze ! "
                f"videoconvert ! videoscale ! {caps} ! mix.sink_{layer.id}")

    def _build_description(self) -> str:
        pv = self.settings["preview"]
        pad_defs = " ".join(
            f"sink_{l.id}::xpos={l.x} sink_{l.id}::ypos={l.y} "
            f"sink_{l.id}::zorder={l.z}"
            for l in self.layers)
        parts = [
            f"compositor name=mix background=black {pad_defs} ! "
            f"video/x-raw,width={pv['width']},height={pv['height']},"
            f"format=BGRA ! tee name=t",
        ]
        for layer in self.layers:
            f = self.library.file_path(layer.name)
            parts.append(self._layer_source(layer, str(f.resolve())))
        parts.append(
            f"t. ! queue ! videoconvert ! "
            f"jpegenc quality={pv['jpeg_quality']} ! "
            "appsink name=preview emit-signals=true max-buffers=2 drop=true")
        if self.settings["output"].get("fullscreen"):
            import sys
            sink = ("d3d11videosink sync=true"
                    if sys.platform == "win32" else "autovideosink sync=true")
            parts.append(f"t. ! queue ! videoconvert ! {sink}")
        return " ".join(parts)

    def rebuild(self) -> bool:
        """Baut die Pipeline neu auf. Atomar: bei Fehler laeuft die alte weiter."""
        with self._lock:
            if not self.layers:
                self.stop()
                self.running = True  # kein Layer, aber "betriebsbereit"
                return True
            desc = self._build_description()
            old = self.pipeline
            try:
                new = Gst.parse_launch(desc)
            except Exception as e:  # noqa: BLE001
                self.last_error = f"parse_launch: {e}"
                print(f"[Engine] FEHLER: {self.last_error}")
                return False
            sink = new.get_by_name("preview")
            if sink:
                sink.connect("new-sample", self._on_frame)
            if new.set_state(
                    Gst.State.PLAYING) == Gst.StateChangeReturn.FAILURE:
                self.last_error = "set_state(PLAYING) fehlgeschlagen"
                print(f"[Engine] FEHLER: {self.last_error}")
                new.set_state(Gst.State.NULL)
                return False
            # Neue Pipeline laeuft -> alte beenden (deren Bus-Monitor
            # beendet sich beim naechsten Poll selbst, da self.pipeline
            # nicht mehr die referenzierte Pipeline ist)
            if old is not None:
                old.set_state(Gst.State.NULL)
            self.pipeline = new
            self.running = True
            self.last_error = None
            self.apply_all()  # Master/Blackout/Alphas auf neue Pads anwenden
            self._monitor = threading.Thread(
                target=self._bus_monitor, daemon=True)
            self._monitor.start()
            return True

    def _bus_monitor(self):
        pipeline = self.pipeline
        if pipeline is None:
            return
        bus = pipeline.get_bus()
        while self.running and self.pipeline is pipeline:
            msg = bus.timed_pop_filtered(
                500 * Gst.MSECOND,
                Gst.MessageType.EOS | Gst.MessageType.ERROR)
            if msg is None:
                continue
            if msg.type == Gst.MessageType.EOS:
                if self.settings["engine"].get("loop_default", True):
                    pipeline.seek_simple(
                        Gst.Format.TIME,
                        Gst.SeekFlags.FLUSH | Gst.SeekFlags.KEY_UNITS,
                        0)
                else:
                    self.playing = False
                    return
            elif msg.type == Gst.MessageType.ERROR:
                err, debug = msg.parse_error()
                self.last_error = f"{err.message} ({debug})"
                print(f"[Engine] GStreamer-Fehler: {self.last_error}")
                return

    def _on_frame(self, sink):
        sample = sink.emit("pull-sample")
        if sample is not None:
            buf = sample.get_buffer()
            self.current_jpeg = buf.extract_dup(0, buf.get_size())
            self.frame_count += 1
        return Gst.FlowReturn.OK

    # ---------------- Layer-Verwaltung ----------------

    def add_layer(self, name: str) -> dict | None:
        with self._lock:
            max_l = int(self.settings["engine"].get("max_layers", 8))
            if len(self.layers) >= max_l:
                self.last_error = f"max. {max_l} Layer"
                return None
            f = self.library.file_path(name)
            if not f.exists():
                self.last_error = f"Datei nicht gefunden: {name}"
                return None
            kind = self.library.kind_of(name)
            if kind is None:
                self.last_error = f"nicht unterstuetzt: {name}"
                return None
            layer = Layer(self._next_id, name, kind)
            self._next_id += 1
            layer.z = len(self.layers)
            pv = self.settings["preview"]
            layer.width = pv["width"]
            layer.height = pv["height"]
            self.layers.append(layer)
            if not self.rebuild():
                self.layers.remove(layer)  # Rollback: Engine unveraendert
                return None
            return layer.to_dict()

    def remove_layer(self, layer_id: int) -> bool:
        with self._lock:
            kept = [l for l in self.layers if l.id != layer_id]
            if len(kept) == len(self.layers):
                return False
            removed = [l for l in self.layers if l.id == layer_id]
            self.layers = kept
            if not self.rebuild():
                self.layers.extend(removed)  # Rollback
                self.layers.sort(key=lambda l: l.z)
                return False
            return True

    def get_layer(self, layer_id: int) -> Layer | None:
        for l in self.layers:
            if l.id == layer_id:
                return l
        return None

    def update_layer(self, layer_id: int, patch: dict
                     ) -> Layer | None:
        with self._lock:
            layer = self.get_layer(layer_id)
            if layer is None:
                return None
            if "alpha" in patch:
                layer.alpha = max(0.0, min(1.0, float(patch["alpha"])))
            if "x" in patch:
                layer.x = int(patch["x"])
            if "y" in patch:
                layer.y = int(patch["y"])
            if "width" in patch:
                layer.width = max(16, min(7680, int(patch["width"])))
            if "height" in patch:
                layer.height = max(16, min(4320, int(patch["height"])))
            if "z" in patch:
                layer.z = max(0, min(15, int(patch["z"])))
            if "name" in patch and patch["name"] != layer.name:
                f = self.library.file_path(str(patch["name"]))
                if not f.exists():
                    return None
                layer.name = str(patch["name"])
                layer.kind = self.library.kind_of(layer.name) or layer.kind
            # Pad-Eigenschaften live setzen (ohne Rebuild)
            self._apply_pad_props(layer)
            return layer

    def _apply_pad_props(self, layer: Layer):
        if self.pipeline is None:
            return
        mix = self.pipeline.get_by_name("mix")
        if mix is None:
            return
        pad = mix.get_static_pad(f"sink_{layer.id}")
        if pad is None:
            return
        pad.set_property("xpos", layer.x)
        pad.set_property("ypos", layer.y)
        pad.set_property("zorder", layer.z)
        pad.set_property("alpha", self._effective_alpha(layer))

    # ---------------- Steuerung ----------------

    def _effective_alpha(self, layer: Layer) -> float:
        if self.blackout:
            return 0.0
        return layer.alpha * self.master

    def apply_all(self):
        with self._lock:
            for l in self.layers:
                self._apply_pad_props(l)
            if self.pipeline is not None and self.layers:
                target = (Gst.State.PLAYING if self.playing
                          else Gst.State.PAUSED)
                current = self.pipeline.get_state(0)[1]
                if current != target:
                    self.pipeline.set_state(target)

    def set_master(self, value: float):
        with self._lock:
            self.master = max(0.0, min(1.0, value))
            self.apply_all()

    def set_blackout(self, on: bool):
        with self._lock:
            self.blackout = bool(on)
            self.apply_all()

    def set_playback(self, playing: bool):
        with self._lock:
            self.playing = bool(playing)
            self.apply_all()

    def retrigger(self):
        with self._lock:
            if self.pipeline is not None:
                self.pipeline.seek_simple(
                    Gst.Format.TIME,
                    Gst.SeekFlags.FLUSH | Gst.SeekFlags.KEY_UNITS, 0)

    # ---------------- DMX (Mapping aus Settings) ----------------

    def apply_dmx(self, channels: bytes, universe: int, seq: int):
        a = self.settings["artnet"]

        def ch(num) -> int:
            if num is None:
                return 0
            i = int(num) - 1
            return channels[i] if 0 <= i < len(channels) else 0

        with self._lock:
            self.dmx_stats["packets"] += 1
            self.dmx_stats["accepted"] += 1
            self.dmx_stats["last_universe"] = universe
            self.dmx_stats["last_seq"] = seq
            self.dmx_stats["last_time"] = time.time()

        start = a.get("layer_start_channel")
        for i, layer in enumerate(self.layers):
            v = ch(None if start is None else start + i)
            if v > 0:
                layer.alpha = v / 255.0
        self.master = ch(a.get("master_channel")) / 255.0 or self.master
        self.apply_all()

        pb = a.get("playback_channel")
        if ch(pb) >= 128:
            self.set_playback(True)
        bo = a.get("blackout_channel")
        if bo is not None:
            self.set_blackout(ch(bo) >= 128)
        rt = a.get("retrigger_channel")
        if rt is not None and ch(rt) >= 128:
            self.retrigger()

    # ---------------- Status ----------------

    def stop(self):
        self.running = False
        if self._monitor is not None:
            self._monitor.join(timeout=1.0)
            self._monitor = None
        if self.pipeline is not None:
            self.pipeline.set_state(Gst.State.NULL)
            self.pipeline = None

    def status(self) -> dict:
        with self._lock:
            return {
                "running": self.running,
                "layers": [self._layer_dict(l) for l in self.layers],
                "master": round(self.master, 3),
                "blackout": self.blackout,
                "playing": self.playing,
                "frames_rendered": self.frame_count,
                "dmx": dict(self.dmx_stats),
                "error": self.last_error,
            }

    def _layer_dict(self, l: Layer) -> dict:
        d = l.to_dict()
        d["effective"] = round(self._effective_alpha(l), 3)
        return d