Indent markup, removing cruft and matching indent lines.

markup_indenter.rb

#!/usr/bin/env ruby

IGNORE = ['BR', 'META', '!DOCTYPE', '!--']

def tab_change(tag)
	tagname = tag.upcase.split(/[\s|>]/).first[1..-1]
	is_open = tag[1] != '/'
	return 0 if IGNORE.include? tagname
	return 0 if is_open && tag.include?("/#{tagname}")
	is_open ? 1 : -1
end

ARGV.each do |file|
	file = File.open(file, 'rb').read

	# Remove Repeated Spaces
	file = file.gsub /\s+/, ' '

	# Remove Line Breaks
	file = file.gsub /\n/, ''

	# Remove spaces between Tags
	file = file.gsub />\s</, '><'

	# Remove Spaces After Tags
	file = file.gsub />\s/, '><'

	# Put one tag per line.
	file = file.gsub /></, ">\n<"

	tabcount = 0
	file = file.split("\n").map do |line|
		change = tab_change line
		tabcount += change if change < 0
		tabs = "  " * tabcount
		tabcount += change if change > 0
		# "#{change == -1 ? '-' : '+'}: #{tabcount}: #{tabs} #{line}"
		"#{tabs}#{line}"
	end.join("\n")


	puts file
end