"""Load authored world content and cross-check origin references.

Language-neutral content integrity: every id an origin references (start
location, start quest, granted items, seeded npc dispositions) must resolve in
world content. New-game construction (client-side, Plan B) relies on this
holding; catching it here fails a broken origin at authoring time, not three
scenes into play.
"""

import json
import os
from pathlib import Path


def _load_ids(dir_path: Path) -> set[str]:
    ids: set[str] = set()
    for f in dir_path.glob("*.json"):
        with open(f) as fh:
            ids.add(json.load(fh)["id"])
    return ids


def load_world(content_root: Path) -> dict[str, set[str]]:
    world = content_root / "world"
    return {
        "locations": _load_ids(world / "locations"),
        "npcs": _load_ids(world / "npcs"),
        "quests": _load_ids(world / "quests"),
        "items": _load_ids(world / "items"),
    }


def load_origin(path: Path) -> dict:
    with open(path) as f:
        return json.load(f)


def unresolved_refs(origin: dict, world: dict[str, set[str]]) -> list[str]:
    missing: list[str] = []
    if origin["start_location_id"] not in world["locations"]:
        missing.append(f"location:{origin['start_location_id']}")
    quest = origin.get("start_quest_id")
    if quest is not None and quest not in world["quests"]:
        missing.append(f"quest:{quest}")
    for grant in origin["inventory_grants"]:
        if grant["item_id"] not in world["items"]:
            missing.append(f"item:{grant['item_id']}")
    for npc_id in origin["disposition_overrides"]:
        if npc_id not in world["npcs"]:
            missing.append(f"npc:{npc_id}")
    return missing


def _content_root() -> Path:
    """Locate the authored content root. Honours CONTENT_ROOT, else walks up
    from this file for a dir containing world/ — repo-root/content in a local
    checkout, /app/content when bundled into the Docker image. Mirrors
    canon_log._schema_dir().
    """
    env = os.environ.get("CONTENT_ROOT")
    if env:
        return Path(env)
    here = Path(__file__).resolve()
    for parent in here.parents:
        candidate = parent / "content"
        if (candidate / "world").is_dir():
            return candidate
    raise RuntimeError("content root not found")


def load_npc(npc_id: str) -> dict | None:
    """Load one NPC's authored file (persona + knowledge + capabilities), or
    None if no file resolves. Server-only fields never travel to the client."""
    path = _content_root() / "world" / "npcs" / f"{npc_id}.json"
    if not path.is_file():
        return None
    with open(path) as f:
        return json.load(f)