defmodule MCP.Supervisor do
  @moduledoc """
  Supervisor for MCP client instances for the current invocation.
  """
  use Supervisor

  alias MCP.Transport
  alias MCP.FnordClient

  @spec start_link(keyword()) :: Supervisor.on_start()
  def start_link(opts \\ []), do: Supervisor.start_link(__MODULE__, opts, name: __MODULE__)

  @impl true
  def init(_opts) do
    settings = Settings.new()
    servers = Settings.MCP.effective_config(settings)

    children =
      Enum.map(servers, fn {server, scfg} ->
        {kind, t_opts} = Transport.map(scfg)
        spec_opts = [name: instance_name(server), transport: {kind, t_opts}]
        Supervisor.child_spec({FnordClient, spec_opts}, id: {:mcp, server})
      end)

    Supervisor.init(children, strategy: :one_for_one)
  end

  @spec instance_name(String.t()) :: atom()
  def instance_name(server), do: String.to_atom("mcp:" <> server)
end