unreal-engine-mcp-system-plugin/ue_side/audio.py

"""Audio ops — MetaSounds, SoundCue, Attenuation, SoundClass/Mix.

Ops:
  create_metasound_source  {path}
  create_metasound_patch   {path}
  create_sound_cue         {path}
  create_sound_attenuation {path}
  create_sound_class       {path}
  create_sound_mix         {path}
  set_property             {path, property, value}
  get_property             {path, property}
  list_sound_assets        {folder?}
  play_sound_2d            {path}                — preview in editor
"""
from __future__ import annotations

import json
import os
import traceback

try:
    import unreal  # type: ignore
except ImportError:
    unreal = None


def _at():
    return unreal.AssetToolsHelpers.get_asset_tools()


def _load(p): return unreal.EditorAssetLibrary.load_asset(p)
def _split(p):
    folder, name = p.rsplit("/", 1)
    return folder, name


def _create(path, asset_cls_name, factory_name):
    folder, name = _split(path)
    cls = getattr(unreal, asset_cls_name, None)
    factory_cls = getattr(unreal, factory_name, None)
    if cls is None or factory_cls is None:
        return {"ok": False, "error": f"{asset_cls_name}/{factory_name} not exposed (plugin disabled?)"}
    asset = _at().create_asset(name, folder, cls, factory_cls())
    if asset is None:
        return {"ok": False, "error": "create_asset returned None"}
    unreal.EditorAssetLibrary.save_asset(asset.get_path_name())
    return {"ok": True, "path": asset.get_path_name().split(".")[0]}


def create_metasound_source(args):  return _create(args["path"], "MetaSoundSource",  "MetaSoundSourceFactory")
def create_metasound_patch(args):   return _create(args["path"], "MetaSoundPatch",   "MetaSoundPatchFactory")
def create_sound_cue(args):         return _create(args["path"], "SoundCue",         "SoundCueFactoryNew")
def create_sound_attenuation(args): return _create(args["path"], "SoundAttenuation", "SoundAttenuationFactory")
def create_sound_class(args):       return _create(args["path"], "SoundClass",       "SoundClassFactory")
def create_sound_mix(args):         return _create(args["path"], "SoundMix",         "SoundMixFactory")


def set_property(args):
    a = _load(args["path"])
    if a is None:
        return {"ok": False, "error": "asset not found"}
    try:
        a.set_editor_property(args["property"], args["value"])
        unreal.EditorAssetLibrary.save_asset(a.get_path_name())
        return {"ok": True}
    except Exception as e:
        return {"ok": False, "error": str(e)}


def get_property(args):
    a = _load(args["path"])
    if a is None:
        return {"ok": False, "error": "asset not found"}
    try:
        v = a.get_editor_property(args["property"])
        return {"ok": True, "value": str(v)}
    except Exception as e:
        return {"ok": False, "error": str(e)}


def list_sound_assets(args):
    folder = args.get("folder") or "/Game"
    ar = unreal.AssetRegistryHelpers.get_asset_registry()
    classes = ["SoundCue", "SoundWave", "MetaSoundSource", "MetaSoundPatch",
               "SoundAttenuation", "SoundClass", "SoundMix", "SoundConcurrency"]
    filt = unreal.ARFilter(package_paths=[folder], recursive_paths=True, class_names=classes)
    items = [{"path": str(d.package_name), "class": str(d.asset_class)} for d in ar.get_assets(filt)]
    return {"ok": True, "count": len(items), "items": items}


def play_sound_2d(args):
    a = _load(args["path"])
    if a is None:
        return {"ok": False, "error": "not found"}
    try:
        world = unreal.EditorLevelLibrary.get_editor_world()
        unreal.GameplayStatics.play_sound2d(world, a)
        return {"ok": True}
    except Exception as e:
        return {"ok": False, "error": str(e)}


OPS = {
    "create_metasound_source":  create_metasound_source,
    "create_metasound_patch":   create_metasound_patch,
    "create_sound_cue":         create_sound_cue,
    "create_sound_attenuation": create_sound_attenuation,
    "create_sound_class":       create_sound_class,
    "create_sound_mix":         create_sound_mix,
    "set_property":             set_property,
    "get_property":             get_property,
    "list_sound_assets":        list_sound_assets,
    "play_sound_2d":            play_sound_2d,
}


def entrypoint(payload_json: str) -> str:
    try:
        p = json.loads(payload_json)
    except Exception as e:
        return _tee({"ok": False, "error": f"bad json: {e}"}, {})
    op = p.get("op")
    fn = OPS.get(op)
    if not fn:
        return _tee({"ok": False, "error": f"unknown op {op!r}", "available": list(OPS)}, p)
    try:
        return _tee(fn(p), p)
    except Exception as e:
        return _tee({"ok": False, "error": str(e), "traceback": traceback.format_exc()}, p)


def _tee(result, p):
    txt = json.dumps(result)
    try:
        if unreal is not None:
            sd = unreal.Paths.project_saved_dir() + "MCP/"
            os.makedirs(sd, exist_ok=True)
            rid = p.get("__rid") or "last"
            with open(sd + "last.json", "w", encoding="utf-8") as f: f.write(txt)
            if rid != "last":
                with open(sd + f"{rid}.json", "w", encoding="utf-8") as f: f.write(txt)
            unreal.log("[MCP-AUDIO] " + txt[:1500])
    except Exception:
        pass
    return txt