Converts Hexa color to RGB(A) color.tmCommand

#!/usr/bin/env ruby

require ENV['TM_SUPPORT_PATH'] + "/lib/exit_codes"

# Converts a HTML color string to a RGB colors string.
#
#    hex_to_css("#6633ff")   # => rgb(102, 51, 255)
#    hex_to_css("#63f")      # => rgb(102, 51, 255)
#    hex_to_css("#6633ff80") # => rgba(102, 51, 255, .50)
#    hex_to_css("#63FA")     # => rgba(102, 51, 255, .67)
#    hex_to_css("#63F0")     # => rgba(102, 51, 255, 0)
def hex_to_css(hex_color)
	raise ArgumentError unless hex_color[0, 1] == '#'

	hex_color.gsub!(/[#;]/, '')
	case hex_color.length
	when 3, 4
		colors = hex_color.scan(%r<[0-9a-f]>i).map { |c| (c * 2).hex }
	when 6, 8
		colors = hex_color.scan(%r<[0-9a-f]{2}>i).map { |c| c.hex }
	else
		raise ArgumentError
	end

	if colors.length == 4
		hex_to_rgba(colors)
	else
		hex_to_rgb(colors)
	end
end

# Present the colors as an RGB HTML/CSS color string.
def hex_to_rgb(colors)
	"rgb(#{colors.join(', ')})"
end

# Present the colors as an RGBA (with alpha) HTML/CSS color string.
def hex_to_rgba(colors)
	opacity = sprintf("%1.2f", colors.last.quo(255)).gsub(%r{([01]).00}, '\1').gsub(%r{^0\.}, '.')
	colors.delete_at(colors.length - 1)
	"rgba(#{colors.join(', ')}, #{opacity})"
end

raw = STDIN.read
begin
	# Line
	if ENV['TM_SELECTED_TEXT'].nil?
		line, col    = ENV['TM_CURRENT_LINE'], ENV['TM_LINE_INDEX'].to_i
		left, before = *(line[0...col].reverse.match(/^([a-f0-9]+)?(#)/i)  || [])[1..2]
		right, after = *(line[col..-1]        .match(/^([a-f0-9]+)?(;)?/i) || [])[1..2]

		if before.nil? or (!after.nil? && right.nil? && left.nil?)
			raise ArgumentError
			exit 1
		end

		(before ||='').reverse!
		(left   ||='').reverse!
		right ||= ''
		after ||= ''
		rgb_color = hex_to_css([before, left, right].join(''))
		color = line[0...(col - left.size - before.size)] + rgb_color + line[(col + right.size)..-1]

	# Selected text
	else
		color = hex_to_css(raw)
	end
	print color
rescue ArgumentError => e
	TextMate.exit_show_tool_tip("Not a valid color: #RGB or #RGBA or #RRGGBB or #RRGGBBAA.")
	exit 1
end