defmodule Pkcs11ex.Application do
  @moduledoc false

  use Application

  @persistent_term_key __MODULE__

  @impl true
  def start(_type, _args) do
    check_files? = Application.get_env(:pkcs11ex, :check_files, true)
    config = Pkcs11ex.Config.load!(check_files: check_files?)
    :persistent_term.put(@persistent_term_key, config)

    children = [
      # PinnedRegistry is started unconditionally (lightweight: one GenServer +
      # one ETS table). Deployments that use a different :trust_policy can
      # leave it idle; deployments that swap in/out at runtime get it for free.
      SignCore.Policy.PinnedRegistry,

      # Slot server registry — name-resolves {slot_ref, worker_index} → pid
      # for the per-slot GenServers under SlotSupervisor. Pool slots have
      # multiple worker_index values; non-pool slots use index 1.
      {Registry, keys: :unique, name: Pkcs11ex.Slot.Registry},

      # Pool dispatcher — owns the ETS table that SlotSupervisor populates
      # with each slot's pool size. Started before SlotSupervisor so the
      # supervisor can register pool sizes during init.
      Pkcs11ex.Slot.Pool,

      # Per-slot GenServers, one per entry in Pkcs11ex.Config :slots
      # (or N per slot for pool slots). Empty config (verify-only
      # deployments) is fine — the supervisor just has no children.
      Pkcs11ex.SlotSupervisor
    ]

    opts = [strategy: :one_for_one, name: Pkcs11ex.Supervisor]
    Supervisor.start_link(children, opts)
  end

  @doc """
  Returns the validated configuration set during application boot.
  """
  @spec config() :: Pkcs11ex.Config.t()
  def config, do: :persistent_term.get(@persistent_term_key)
end