Rack/plugins/community/repos/DHE-Modules/gui/lib/controls/label.rb

require_relative '../control'

module DHE
  class Label < Control
    BASELINES = {above: 'alphabetic', below: 'hanging', right_of: 'middle'}
    ANCHORS = {above: 'middle', below: 'middle', right_of: 'start'}
    ASCENT_RATIO = 2.0 / 3.0 # Approximately correct for Proxima Nova font
    SIZES = {title: 12.0 / PX_PER_MM, large: 9.0 / PX_PER_MM, small: 7.0 / PX_PER_MM}

    def initialize(faceplate:, text:, size:, x:, y:, style: :normal, alignment: :above, transform: :upper)
      @x = x
      @y = y
      @text = text
      @size = SIZES[size.to_sym]
      @color = style == :normal ? faceplate.foreground : faceplate.background
      @alignment = alignment
      @baseline = BASELINES[@alignment]
      @anchor = ANCHORS[@alignment]
      height = @size * ASCENT_RATIO
      width = @text.length * @size * 0.6 # Approximate
      left = case alignment
             when :right_of
               x
             else # above or below
               x - width / 2
             end
      top = case alignment
            when :above
              y - height
            when :right_of
              y - height / 2
            else # below
              y
            end
      bottom = top + height
      right = left + width
      super(faceplate: faceplate, x: x, y: y, top: top, right: right, bottom: bottom, left: left)
    end

    def draw(svg:, x:, y:)
      svg.text(x: x, y: y, 'dominant-baseline' => @baseline, 'text-anchor' => @anchor, fill: @color, style: "font-family:Proxima Nova;font-weight:bold;font-size:#{@size}px") do |text|
        text << @text
      end
    end
  end
end