"""ever-brain use <name> — Activate a Brain Instance globally."""

import typer

from brain.config import set_active_brain
from brain.paths import get_brain_path
from brain.utils.display import error, success


def use(name: str = typer.Argument(..., help="Name of the Brain Instance to activate")) -> None:
    """Set the active Ever Brain Instance globally (system-wide)."""
    brain_path = get_brain_path(name)

    if not brain_path.exists():
        error(f"Ever Brain instance '{name}' not found.")
        error(f"Expected at: {brain_path}")
        raise typer.Exit(code=1)

    set_active_brain(brain_path)
    success(f"Active Ever Brain set to '{name}'.")