"""Stabile Parameterpfade (PLAN.md §10.2).

Pfade werden niemals aus sichtbaren Namen gebildet; alle Teile sind UUIDs
oder feste Schlüsselwörter.
"""

from __future__ import annotations

import uuid

_ALLOWED_ROOTS = {"composition", "output", "cluster", "master"}


def _is_uuid(value: str) -> bool:
    try:
        uuid.UUID(value)
        return True
    except (ValueError, AttributeError):
        return False


def validate_parameter_path(path: str) -> bool:
    """True, wenn der Pfad dem Muster §10.2 entspricht."""
    if not path or path.startswith("/") or "\\" in path or ".." in path:
        return False
    parts = path.split("/")
    root = parts[0]
    if root not in _ALLOWED_ROOTS:
        return False
    if root == "master":
        return len(parts) == 2 and parts[1] != ""
    if root in {"composition", "output"}:
        if len(parts) < 3:
            return False
        if not _is_uuid(parts[1]):
            return False
        return all(p != "" for p in parts[2:])
    # cluster: cluster/group/{uuid}/... oder cluster/node/{uuid}/...
    if len(parts) >= 3 and parts[1] in {"group", "node"} and _is_uuid(parts[2]):
        return all(p != "" for p in parts[3:])
    return False


def layer_opacity_path(composition_id: str, layer_id: str) -> str:
    return f"composition/{composition_id}/layer/{layer_id}/opacity"


def master_intensity_path() -> str:
    return "master/intensity"