"""Executable lookup for ``external_process`` (ACP) providers.

A GUI/service launch (LaunchAgent, Desktop backend, Desktop over SSH) has a bare PATH, so the
profile's command resolves through PATH, then the user-local bin, then Claude Code's install
prefixes."""

from __future__ import annotations

import os
from typing import Optional


def resolve_external_process_command(command: str) -> Optional[str]:
    """Absolute path of the provider CLI ``command``, or ``None`` when nothing executable matches."""
    if not command:
        return None
    from hermes_platform.resolver import locate_command
    from hermes_platform.resolver.known_dirs import user_local_bin

    lookup = command
    if os.sep in command or (os.altsep and os.altsep in command):
        # An operator-configured relative path (./bin/copilot) means the launch cwd, as it did
        # under shutil.which; anchor it so the resolver's absolute-only explicit check accepts it.
        lookup = os.path.abspath(os.path.expandvars(os.path.expanduser(command)))
    found = locate_command(lookup, known_dirs=user_local_bin()).command
    if found:
        # Known dirs are written with "/" (%USERPROFILE%/.local/bin); normalize so a Windows hit
        # reads as one native path in status and in the spawned argv.
        return os.path.normpath(found[0])
    from agent.anthropic_adapter import find_claude_code_cli

    return find_claude_code_cli(command)