"""MiniApps API — universal registry listing (Phase M1).

Platform-level endpoint (the registry is a platform concept, not owned by
a single plugin): lists MiniApps with server-side permission filtering
(fail-closed) and optional host filter.
"""

from __future__ import annotations

from fastapi import APIRouter, Depends, HTTPException

from app.core.permissions import check_permission
from app.deps import get_current_user
from app.plugins.miniapp_registry import get_miniapp_registry

router = APIRouter(prefix="/api/v1/miniapps", tags=["miniapps"])


def _user_permits(current_user: dict, app: dict) -> bool:
    """Empty permission = visible to everyone; otherwise fail-closed check."""
    required = app.get("permission") or ""
    if not required:
        return True
    if current_user.get("is_system_admin"):
        return True
    return check_permission(current_user, required)


@router.get("")
async def list_miniapps(
    host: str | None = None,
    current_user: dict = Depends(get_current_user),
):
    """List MiniApps visible to the current user (permission-filtered).

    ``?host=chat|dashboard|window`` filters by the hosts declared on the
    MiniApp definition.
    """
    registry = get_miniapp_registry()
    items = [a for a in registry.list_apps(host=host) if _user_permits(current_user, a)]
    items.sort(key=lambda a: a.get("order", 100))
    return {"items": items, "total": len(items)}


@router.get("/{app_id}")
async def get_miniapp(
    app_id: str,
    current_user: dict = Depends(get_current_user),
):
    """Get a single MiniApp definition (403 without permission, 404 unknown)."""
    app = get_miniapp_registry().get_app(app_id)
    if app is None:
        raise HTTPException(404, detail={"detail": "MiniApp not found", "code": "not_found"})
    data = app.model_dump()
    if not _user_permits(current_user, data):
        raise HTTPException(
            403,
            detail={
                "detail": f"Permission '{data['permission']}' required",
                "code": "forbidden",
            },
        )
    return data