require 'rest-client'

def optimize css
	css = css.dup
	
	# Remove whitespace around CSS selectors: a + b, a > b, etc.
	css.gsub! ' + ', '+'
	css.gsub! ' > ', '>'
	
	# Remove whitespace inside parentheses: ( foo )
	css.gsub! '( ', '('
	css.gsub! ' )', ')'
	
	# Remove leading '0.' from CSS values
	css.gsub! ':0.', ':.'
	css.gsub! ' 0.', ' .'
	css.gsub! ',0.', ',.'
	css.gsub! '(0.', '(.'
	
	# Ensure hex colors are output in shorthand notation: #fff
	css.gsub! /\#([0-9a-f])\1([0-9a-f])\2([0-9a-f])\3\b/, '#\1\2\3'
	
	# Remove domain from URLs like //xx.wikipedia.org/w/load.php?...
	css.gsub! '//en.wikipedia.org', ''
	
	# Remove whitespace and ids from embedded SVG files
	css.gsub! /url\(data:image\/svg\+xml,(.+)\)/ do
		data = $1.dup
		data.gsub! '%0A', '%20'
		data.gsub! /(%20)+/, '%20'
		data.gsub! /(%20)+/, '%20'
		data.gsub! '%3E%20%3C', '%3E%3C'
		data.gsub! /%20id%3D%22(.+?)%22/, ''
		data
	end
	
	css
end

def test text
	pipe = IO.popen(['gzip'], 'rb+')
	pipe.write(text)
	pipe.close_write()
	gzipped = pipe.read()
	"len: #{text.length} gzip: #{gzipped.length}"
end

samples = [
	'https://en.wikipedia.org/w/load.php?modules=oojs-ui.styles%7Coojs-ui.styles.icons%7Coojs-ui.styles.indicators%7Coojs-ui.styles.textures&only=styles',
	'https://en.wikipedia.org/w/load.php?modules=ext.cite.styles%7Cext.gadget.DRN-wizard%2CReferenceTooltips%2CWatchlistBase%2CWatchlistGreenIndicators%2Ccharinsert%2Cfeatured-articles-links%2CrefToolbar%2Cswitcher%2Cteahouse%7Cext.tmh.thumbnail.styles%7Cext.uls.nojs%7Cext.visualEditor.desktopArticleTarget.noscript%7Cext.wikimediaBadges%7Cmediawiki.legacy.commonPrint%2Cshared%7Cmediawiki.raggett%2CsectionAnchor%7Cmediawiki.skinning.interface%7Cskins.vector.styles%7Cwikibase.client.init&only=styles',
]

samples.each{|url|
	puts url
	text = RestClient.get(url)
	optim = optimize text
	puts "currently: #{test text}"
	puts "optimized: #{test optim}"
}