| """JSON-only contracts for grouped project audio; no media or runtime imports.""" | |
| AUDIO_TRACK_ROLES = ("full_mix", "vocals", "instrumental") | |
| def audio_track_bindings(value, assets): | |
| if value is None: | |
| return None | |
| if not isinstance(value, dict) or set(value) - set(AUDIO_TRACK_ROLES): | |
| raise ValueError("Audio tracks must map full_mix, vocals, and instrumental to asset IDs.") | |
| known = {str(asset.get("id") or ""): asset for asset in assets} | |
| result = {} | |
| for role in AUDIO_TRACK_ROLES: | |
| raw = value.get(role, "") | |
| if raw is not None and not isinstance(raw, str): | |
| raise ValueError("Audio track IDs must be strings.") | |
| asset_id = str(raw or "").strip() | |
| if asset_id and (asset_id not in known or known[asset_id].get("kind") != "audio"): | |
| raise ValueError("Audio track %s must reference an existing audio asset in this project." % role) | |
| result[role] = asset_id | |
| selected = [asset_id for asset_id in result.values() if asset_id] | |
| if not selected: | |
| raise ValueError("Select at least one audio track, or reset to the original single track.") | |
| if len(selected) != len(set(selected)): | |
| raise ValueError("The same audio asset cannot be both a mix and a stem, or both stems.") | |
| return result | |