defmodule ElementTui.Components.Tab do
  alias ElementTui.Components.Tab

  defstruct id: nil, render: nil

  def new(id, func) do
    %Tab{id: id, render: func}
  end
end

defmodule ElementTui.Components.TabList do
  alias ElementTui.Element
  alias ElementTui.FocusStream

  @side_chars {"│", "│", "┃", "┃"}

  def new(tabs) do
    FocusStream.new(tabs)
  end

  def next(state) do
    FocusStream.next(state, bound: true)
  end

  def prev(state) do
    FocusStream.prev(state, bound: true)
  end

  def render(state, x, y, width, height) do
    # Render the tabs
    xs =
      state
      |> FocusStream.map(fn tb, is_cursor ->
        case is_cursor do
          true ->
            Element.text_line(elem(@side_chars, 2) <> tb.id <> elem(@side_chars, 3))
            |> Element.bold()

          false ->
            Element.text_line(elem(@side_chars, 0) <> tb.id <> elem(@side_chars, 1))
        end
      end)

    ElementTui.render(Element.hbox(xs), x, y, width, 1)

    # Render the active tab
    tb = FocusStream.peek(state)
    tb.render.(x, y + 1, width, height - 1)
  end
end