"""Expose hermes-agent's COMMAND_REGISTRY to the webui frontend.

This module is the single integration point with hermes_cli.commands.
If hermes-agent is unavailable the endpoint degrades to an empty list
so the frontend can still load with WEBUI_ONLY commands.
"""
from __future__ import annotations
import logging
from typing import Any

logger = logging.getLogger(__name__)

# Commands that are gateway_only in the agent registry -- webui never
# wants to expose them (sethome, restart, update etc.) even if a future
# agent version drops the gateway_only flag. /commands is the agent's
# own command-listing command; webui has its own /help that calls
# cmdHelp() locally, so /commands would be redundant and confusing.
_NEVER_EXPOSE: frozenset[str] = frozenset({
    'sethome', 'restart', 'update', 'commands',
})


def list_commands(_registry=None) -> list[dict[str, Any]]:
    """Return COMMAND_REGISTRY entries as JSON-friendly dicts.

    Returns empty list if hermes_cli is not installed (graceful
    degradation -- the frontend has its own fallback minimum set).

    Args:
        _registry: Optional injected registry for testing. When None
            (production), imports COMMAND_REGISTRY from hermes_cli.
    """
    if _registry is None:
        try:
            from hermes_cli.commands import COMMAND_REGISTRY as _registry
        except ImportError:
            logger.warning("hermes_cli.commands not importable -- /api/commands returns []")
            return []

    out: list[dict[str, Any]] = []
    for cmd in _registry:
        if cmd.gateway_only:
            continue
        if cmd.name in _NEVER_EXPOSE:
            continue
        out.append({
            'name': cmd.name,
            'description': cmd.description,
            'category': cmd.category,
            'aliases': list(cmd.aliases),
            'args_hint': cmd.args_hint,
            'subcommands': list(cmd.subcommands),
            'cli_only': bool(cmd.cli_only),
            'gateway_only': bool(cmd.gateway_only),
        })
    return out