#!/usr/bin/env ruby
# Author: Joseph Pecoraro
# Date: Sunday, June 7, 2009
# Description: Tree Listing of a Directory
# Delim and Spacer work best when they are the same length
 
class DirTree
 
	def self.list(dir=Dir.pwd, delim='+-', spacer='| ', hidden=false)
		list = []
		depth = []
		Dir.chdir(dir)
		spacer_length=spacer.length
		prefix = [' '*delim.length]
		list = hidden ? Dir.glob('**/*', File::FNM_DOTMATCH).delete_if { |x| x=~/\.(\.|DS_Store)?$/ } : Dir['**/*']
		puts "#{delim}#{File.basename(dir)}"
		list.each_with_index do |filename, index|
			orig = filename.dup
 
			# Check Depth Array against next string
			i = 0
			depth.each do |lvl|
				unless filename.sub!(/^#{lvl}\//,'').nil?
					i += 1
				else
					break
				end
			end
 
			# Clean the Prefix - Chop characters off the end
			while i != depth.size
				depth.pop
				prefix.pop
			end
 
			# Output No Leading Pipe if nothing is on the same level
			print "#{prefix.join}#{delim}#{filename}"
			if File.directory?(orig)
				print '/'
				another = false
				dir_prefix = depth.join('/')
				index.upto(list.size-1) do |n|
					str = list[n]
					if str =~ /^#{dir_prefix}/
						str = str.sub(/^#{dir_prefix}\/?/,'')
						if str !~ /^#{filename}/
							another = true
							break
						end
					end
				end
				depth << filename
				prefix << ( (another) ? spacer : ' '*spacer_length )
			end
			puts
 
		end
	end
 
end
 
 
# When Run as a Script
if $0 == __FILE__
	trap("INT") { puts "\nInterrupted."; exit }
	require 'optparse'
	hidden = false
	OptionParser.new do |opts|
		opts.banner =  "usage: tree [options] [dir ...]"
		opts.on('-a', '--all', 'Show hidden files') { hidden = true }
		opts.on('-h', '--help', 'Show this help.') { puts opts; exit }
	end.parse!
	ARGV << '.' if ARGV.empty?
	ARGV.each do |dir|
		DirTree.list( File.expand_path(dir), '+--', '|  ', hidden )
		puts
	end
end