#!/usr/bin/ruby

class UUdecoder
	attr_accessor :skip_header
	def initialize
		@outfile = nil
		@finished = nil
		@skip_header = false
	end

	# returns true if you should pass the next line here
	def parse_line(l)
		l = l.chomp
		if not @outfile
			if l =~ /^begin \d\d\d (.*)/
				puts "uudec: decoding #{$1.inspect}"
				file = $1.gsub(/[^a-zA-Z0-9_.+\-\[\]\(\)#'" ]/, '_')
				@outfile = File.open(file, 'w')
				@finished = false
				true
			end
		elsif @finished
			puts "uudec: should have found 'end' keyword" if l != 'end'
			puts "uudec: finished" if $VERBOSE
			@outfile.close
			@outfile = nil
			@finished = false
			false
		elsif @outfile
			unless l.empty?
				l = uudecode_line l
				@outfile.write l
				@finished = l.empty?
			end
			true
		end

	end

	def process_line(line)
		if line.empty?
			@skip_header = false
		elsif @skip_header
			# nop
		elsif not @outfile
			if line =~ /^begin \d\d\d (.*)/
				file = $1.gsub(/[^a-zA-Z0-9_.+\-\[\]\(\)#'" ]/, '_')
				@outfile = File.open(file, 'w')
				@finished = false
			end
		elsif @finished
			puts "Should have found 'end' keyword" if line != 'end'
			@outfile.close
			@outfile = nil
			@finished = false
		else
			l = uudecode_line line
			@outfile.write l
			@finished = l.empty?
		end
	end

	def process_files(filelist)
		filelist.each { |f|
			@skip_header = true
			IO.foreach(f) { |l| process_line l.chomp }
		}
	end

	def uudec(c)
		(c - 32) & 0x3F
	end

	# this is horrible
	def uudecode_line(line)
		len = uudec line[0]
		a, b, c, d = nil
		line[1..-1].scan(/(.)(.)(.)(.)/).map { |a, b, c, d|
			[(uudec(a[0]) << 26) + (uudec(b[0]) << 20) + (uudec(c[0]) << 14) + (uudec(d[0]) << 8)].pack('N').chop!
		}.join[0, len]
	end
end

if $0 == __FILE__
uudec = UUdecoder.new

if ARGV.empty?
	ARGF.each_line { |l| uudec.process_files(l.chomp.split(/\s+/)) }
else
	uudec.process_files ARGV
end
end