diff options
Diffstat (limited to 'app/helpers/colors_helper.rb')
-rw-r--r-- | app/helpers/colors_helper.rb | 23 |
1 files changed, 23 insertions, 0 deletions
diff --git a/app/helpers/colors_helper.rb b/app/helpers/colors_helper.rb new file mode 100644 index 00000000000..bc72122220a --- /dev/null +++ b/app/helpers/colors_helper.rb @@ -0,0 +1,23 @@ +# frozen_string_literal: true + +module ColorsHelper + HEX_COLOR_PATTERN = /\A\#(?:[0-9A-Fa-f]{3}){1,2}\Z/.freeze + + def hex_color_to_rgb_array(hex_color) + raise ArgumentError, "invalid hex color `#{hex_color}`" unless hex_color =~ HEX_COLOR_PATTERN + + hex_color.length == 7 ? hex_color[1, 7].scan(/.{2}/).map(&:hex) : hex_color[1, 4].scan(/./).map { |v| (v * 2).hex } + end + + def rgb_array_to_hex_color(rgb_array) + raise ArgumentError, "invalid RGB array `#{rgb_array}`" unless rgb_array_valid?(rgb_array) + + "##{rgb_array.map{ "%02x" % _1 }.join}" + end + + private + + def rgb_array_valid?(rgb_array) + rgb_array.is_a?(Array) && rgb_array.length == 3 && rgb_array.all?{ _1 >= 0 && _1 <= 255 } + end +end |