# From: https://github.com/AndyObtiva/glimmer-dsl-swt/blob/development/docs/reference/GLIMMER_SAMPLES.md#hello-canvas-path

require 'glimmer-dsl-swt'

class HelloCanvasPath
  include Glimmer::UI::Application

  after_body do
    regenerate
  end

  body {
    shell {
      grid_layout {
        margin_width 0
        margin_height 0
        margin_top 5
      }

      text 'Hello, Canvas Path!'
      minimum_size 800, 700

      @button = button {
        layout_data :center, :center, true, false

        text 'Regenerate'
        enabled false

        on_widget_selected do
          regenerate
        end
      }

      canvas {
        layout_data :fill, :fill, true, true
        background :white

        text('line', 15, 200) {
          foreground :red
        }
        @path1 = path {
          antialias :on
          foreground :red
        }

        text('quad', 15, 300) {
          foreground :dark_green
        }
        @path2 = path {
          antialias :on
          foreground :dark_green
        }

        text('cubic', 15, 400) {
          foreground :blue
        }
        @path3 = path {
          antialias :on
          foreground :blue
        }
      }

      on_widget_disposed do
        # safe to kill thread as data is in memory only, so no risk of data loss
        @thread.kill
      end
    }
  }

  def regenerate
    @thread = Thread.new do
      @button.enabled = false
      @path1.clear
      @path2.clear
      @path3.clear
      y1 = y2 = y3 = 300
      700.times.each do |x|
        x += 55
        x1 = x - 2
        x2 = x - 1
        x3 = x
        y1 = y3
        y2 = y1
        y3 = [[y3 + (rand*24 - 12), 0].max, 700].min
        @path1.content {
          line(x1, y1 - 100)
        }
        if x % 2 == 0
          @path2.content {
            quad(x1, y1, x2, y2)
          }
        end
        if x % 3 == 0
          @path3.content {
            cubic(x1, y1 + 100, x2, y2 + 100, x3, y3 + 100)
          }
        end
        sleep(0.01)
      end
      @button.enabled = true
    end
  end
end

HelloCanvasPath.launch