"""``hermes fallback`` subcommand parser.

Extracted from ``hermes_cli/main.py:main()`` (god-file Phase 2 follow-up).
Handlers are injected or imported lazily so this module never imports ``main``.
"""

from __future__ import annotations


def build_fallback_parser(subparsers) -> None:
    """Attach the ``fallback`` subcommand to ``subparsers``."""
    from hermes_cli.fallback_cmd import cmd_fallback

    fallback_parser = subparsers.add_parser(
        "fallback",
        help="Manage fallback providers (tried when the primary model fails)",
        description=(
            "Manage the fallback provider chain.  Fallback providers are tried "
            "in order when the primary model fails with rate-limit, overload, or "
            "connection errors.  See: "
            "https://hermes-agent.nousresearch.com/docs/user-guide/features/fallback-providers"
        ),
    )
    fallback_subparsers = fallback_parser.add_subparsers(dest="fallback_command")
    fallback_subparsers.add_parser(
        "list",
        aliases=["ls"],
        help="Show the current fallback chain (default when no subcommand)",
    )
    fallback_subparsers.add_parser(
        "add",
        help="Pick a provider + model (same picker as `hermes model`) and append to the chain",
    )
    fallback_subparsers.add_parser(
        "remove",
        aliases=["rm"],
        help="Pick an entry to delete from the chain",
    )
    fallback_subparsers.add_parser(
        "clear",
        help="Remove all fallback entries",
    )
    fallback_parser.set_defaults(func=cmd_fallback)