defmodule SnapFramework.Parser.Outlet do
  require Logger

  @moduledoc false

  def run(ast, assigns) do
    ast
    |> parse(assigns)
  end

  # -----------------------------------------------
  # render the list of slot component passed to the
  # outlet component if it matches the slot_name
  # -----------------------------------------------
  def parse({:outlet, meta, [slot_name, opts]}, assigns) do
    # graph_val = Macro.var(:graph_val, SnapFramework.Engine)
    slot = assigns[:state][:data][:slots][slot_name] || nil

    case slot do
      {nil, _, _} ->
        quote do
          nil
        end

      {cmp, data, nil} ->
        quote line: meta[:line] || 0 do
          # unquote(graph_val) =
          [
            type: :component,
            module: unquote(cmp),
            data: unquote(data),
            opts: unquote(opts)
          ]
        end

      {cmp, data, cmp_opts} ->
        quote line: meta[:line] || 0 do
          # unquote(graph_val) =
          [
            type: :component,
            module: unquote(cmp),
            data: unquote(data),
            opts: unquote(cmp_opts)
          ]
        end

      _ ->
        quote do
          nil
        end
    end
  end

  # -----------------------------------------------
  # render the slot component for unnamed outlet
  # used typically to render a list of components
  # -----------------------------------------------
  def parse({:outlet, _meta, [opts]}, assigns) do
    # graph_val = Macro.var(:graph_val, SnapFramework.Engine)
    slots = assigns[:state][:data][:slots] || nil

    Enum.reduce(slots, [], fn {:slot, slot}, acc ->
      case slot do
        {nil, _, _} ->
          quote do
            unquote(acc)
          end

        {cmp, data, nil} ->
          quote do
            # var!(cmp) = cmp
            # unquote(cmp)(unquote(acc), unquote(data), unquote(opts))
            List.insert_at(
              unquote(acc),
              length(unquote(acc)),
              type: :component,
              module: unquote(cmp),
              data: unquote(data),
              opts: unquote(opts)
            )
          end

        {cmp, data, cmp_opts} ->
          quote do
            # var!(cmp) = cmp
            # unquote(cmp)(unquote(acc), unquote(data), Vector2.add(unquote(opts), unquote(cmp_opts)))
            List.insert_at(
              unquote(acc),
              length(unquote(acc)),
              type: :component,
              module: unquote(cmp),
              data: unquote(data),
              opts: unquote(cmp_opts)
            )
          end

        _ ->
          quote do
            unquote(acc)
          end
      end
    end)
  end

  def parse(ast, _assigns), do: ast
end