Convert NSDictionary/NSArray to literal syntax

convert.rb

#!/usr/bin/env ruby
# encoding: utf-8

require 'strscan'

def construct_dict_literal(pairs, mutable = false)
  output = pairs.each_slice(2).reduce('@{') {
    |expr, pair|
    value, key = *pair
    expr << key.strip   << ': '
    expr << value.strip << ', '
  }[0...-2] << '}'

  mutable ? "[#{output} mutableCopy]" : output
end

def construct_array_literal(list, mutable = false)
  output = list.reduce('@[') { |expr, item|
    expr << item.strip << ', '
  }[0...-2] << ']'

  mutable ? "[#{output} mutableCopy]" : output
end

expr = ARGV.join('')
expr = expr.force_encoding("UTF-8")
expr = expr.gsub(/\n/, '').gsub(/\s+/, ' ')

class Scanner < StringScanner
  def dictionary?
    scan(/\[\s*NSDictionary\s+dictionaryWithObjectsAndKeys:/) ||
      scan(/\[\s*\[NSDictionary\s+alloc\]\s+initWithObjectsAndKeys:/)
  end

  def mutable_dictionary?
    scan(/\[\s*NSMutableDictionary\s+dictionaryWithObjectsAndKeys:/) ||
      scan(/\[\s*\[NSMutableDictionary\s+alloc\]\s+initWithObjectsAndKeys:/)
  end

  def array?
    scan(/\[\s*NSArray\s+arrayWithObjects:/) ||
      scan(/\[\s*\[NSArray\s+alloc\]\s+initWithObjects:/)
  end

  def mutable_array?
    scan(/\[\s*NSMutableArray\s+arrayWithObjects:/) ||
      scan(/\[\s*\[NSMutableArray\s+alloc\]\s+initWithObjects:/)
  end
end

scanner = Scanner.new(expr)
scanner.skip(/\s+/)

if scanner.dictionary?

  pairs = scanner.scan_until(/nil/).split(',')[0...-1]
  puts construct_dict_literal(pairs).force_encoding("UTF-8")

elsif scanner.mutable_dictionary?

  pairs = scanner.scan_until(/nil/).split(',')[0...-1]
  puts construct_dict_literal(pairs, true).force_encoding("UTF-8")

elsif scanner.array?

  items = scanner.scan_until(/nil/).split(',')[0...-1]
  puts construct_array_literal(items).force_encoding("UTF-8")

elsif scanner.mutable_array?

  items = scanner.scan_until(/nil/).split(',')[0...-1]
  puts construct_array_literal(items, true).force_encoding("UTF-8")

else

  puts ":("

end