@type t() :: %{
  session_id: String.t(),
  server_module: module(),
  protocol_version: String.t() | nil,
  protocol_module: module() | nil,
  initialized: boolean(),
  client_info: map() | nil,
  client_capabilities: map() | nil,
  log_level: String.t() | nil,
  frame: Anubis.Server.Frame.t(),
  server_info: map(),
  capabilities: map(),
  instructions: String.t() | nil,
  supported_versions: [String.t()],
  transport: %{layer: module(), name: GenServer.name()},
  registry: module(),
  session_idle_timeout: pos_integer(),
  expiry_timer: reference() | nil,
  pending_requests: %{
    required(String.t()) => %{started_at: integer(), method: String.t()}
  },
  server_requests: %{
    required(String.t()) => %{method: String.t(), timer_ref: reference()}
  },
  timeout: pos_integer(),
  task_supervisor: GenServer.name(),
  task_store: %{adapter: module(), name: term()} | nil,
  tasks: %{required(String.t()) => task_runtime()},
  task_refs: %{required(reference()) => String.t()},
  in_flight:
    nil
    | %{
        ref: reference(),
        pid: pid(),
        request_id: String.t(),
        from: GenServer.from(),
        started_at: integer(),
        method: String.t()
      },
  request_queue: :queue.queue({map(), map(), GenServer.from()}),
  deferred_callbacks: :queue.queue({:cast | :info, term()})
}

@type task_runtime() :: %{
  worker_ref: reference() | nil,
  worker_pid: pid() | nil,
  ttl_timer: reference() | nil,
  waiters: [task_waiter()],
  request_id: String.t() | integer()
}

@type task_waiter() ::
  {from :: GenServer.from(), request_id :: String.t() | integer()}