#!/usr/bin/env ruby
# == Synopsis
#
# uninstall: uninstalls pkgs from OSX
#
# == Usage
#
# uninstall --pkgpath /Library/Receipts/SomPackage-x.y.z.pkg [--prefix backup-prefix]
#
# -p, --pkgpath
#    path to package info
#
# -o, --prefix
#    location for backup dir
#

require 'Fileutils'
require 'getoptlong'
require 'rdoc/usage'

class LsBomParser
	attr_reader :path, :mode, :uid, :gid, :size, :type
	def initialize(line)
		@line = line
		(@path,@mode,tmp,@size) = line.split(/\s+/, 5)
		(@uid, @gid) = tmp.split('/',2)
		if @size.empty?
			@type = 'd'
		else
			@type = 'f'
		end
		@path = '/' + @path
	end

	def to_s
		return @path
	end
end

class OSXPkg
	def initialize(pkgpath)
		@pkgpath = pkgpath
	end

	def get_contents()
		lsbom = IO.popen('/usr/bin/lsbom \'' + @pkgpath + '/Contents/Archive.bom\'')
		contents = Array.new
		lsbom.readlines.each do |l|
			contents.push(LsBomParser.new(l))
		end

		tmp = Hash.new
		contents.each do |item|
			index = item.path.split('/').length
			tmp[index] = Array.new if tmp[index].nil?
	
			tmp[index].push(item)
		end

		ret = Array.new
		tmp.keys.sort.reverse.each do |index|
			ret.concat(tmp[index])
		end
		return ret
	end
end

opts = GetoptLong.new(
	[ '--help', '-h', GetoptLong::NO_ARGUMENT ],
	[ '--pkgpath', '-p', GetoptLong::REQUIRED_ARGUMENT ],
	[ '--prefix', '-o', GetoptLong::REQUIRED_ARGUMENT ]
)

pkgpath = nil
prefix = nil

opts.each do |opt, arg|
	case opt
		when '--help'
			RDoc::usage
		when '--pkgpath'
			pkgpath = arg.to_s
        when '--prefix'
			prefix = arg.to_s
	end
end

if pkgpath == nil
	puts "Missing pkgpath argument (try --help)"
	exit 0
end

if prefix == nil
	prefix = ENV['HOME'] + '/' + File.basename(pkgpath)
end

OSXPkg.new(pkgpath).get_contents.each do |e|
	if e.type == 'f'
		dirname = File.dirname(e.path)
		FileUtils.mkdir_p("#{prefix}/#{dirname}")
		FileUtils.mv(e.path, "#{prefix}/#{e.path}")
		#FileUtils.rm "#{e.path}", :force => true
		puts "mkdir -p '#{prefix}/#{dirname}'"
		puts "mv '#{e.path}' '#{prefix}/#{e.path}'"
		#puts "rm -f -- '#{e.path}'"
	elsif e.type == 'd' and (Dir.entries(e.path).nitems == 2)
		Dir.unlink(e.path)
		puts "rmdir -- '#{e.path}'"
	end
end

# Move pkginfo folder to backup dir
FileUtils.mkdir_p("#{prefix}/Library/Receipts")
FileUtils.mv(pkgpath, "#{prefix}/Library/Receipts/#{File.basename(pkgpath)}")
puts "mkdir -p #{prefix}/Library/Receipts"
puts "mv #{pkgpath} #{prefix}/Library/Receipts/#{File.basename(pkgpath)}"