module CyberarmEngine
  class Element
    class ListBox < Button
      attr_accessor :items
      attr_reader :choose

      def initialize(options = {}, block = nil)
        @items = options[:items] || []
        @choose = options[:choose] || @items.first

        super(@choose, options, block)

        @style.background_canvas.background = default(:background)

        # TODO: "Clean Up" into own class?
        @menu = Stack.new(parent: self, theme: @options[:theme])
        @menu.define_singleton_method(:recalculate_menu) do
          @x = @__list_box.x
          @y = @__list_box.y + @__list_box.height

          @y = @__list_box.y - height if @y + height > window.height
        end
        @menu.instance_variable_set(:"@__list_box", self)

        def @menu.recalculate
          super

          recalculate_menu
        end

        self.choose = @choose
      end

      def render
        super

        w = @text.textobject.text_width("▼")
        @text.textobject.draw_text("▼", @x + content_width - w, @y + @style.padding_top, @z, 1, 1, @text.color)
      end

      def choose=(item)
        valid = @items.detect { |i| i == item }
        raise "Invalid value '#{item}' for choose, valid options were: #{@items.map { |i| "#{i.inspect}" }.join(", ")}" unless valid

        @choose = item

        self.value = item.to_s

        recalculate
      end

      def released_left_mouse_button(_sender, _x, _y)
        show_menu

        :handled
      end

      def clicked_left_mouse_button(_sender, _x, _y)
        # @block&.call(self.value) if @enabled

        :handled
      end

      def show_menu
        @menu.clear

        @menu.style.width = width

        @items.each do |item|
          next if item == self.value

          btn = Button.new(
            item,
            {
              parent: @menu,
              width: 1.0,
              theme: @options[:theme],
              margin: 0,
              border_color: 0x00ffffff
            },
            proc do
              self.choose = item
              @block&.call(self.value)
            end
          )

          @menu.add(btn)
        end
        recalculate

        root.gui_state.show_menu(@menu)
      end

      def recalculate
        super

        @menu.recalculate
      end
    end
  end
end