module CFnDK

# File lib/cfndk/diff.rb, line 5
def self.diff(data_old, data_new)
  result = ''

  file_length_difference = 0

  data_old = data_old.split($/).map { |e| e.chomp }
  data_new = data_new.split($/).map { |e| e.chomp }

  diffs = Diff::LCS.diff(data_old, data_new)
  diffs = nil if diffs.empty?

  return '' unless diffs

  oldhunk = hunk = nil

  diffs.each do |piece|
    begin
      hunk = Diff::LCS::Hunk.new(data_old, data_new, piece, LINES, file_length_difference)
      file_length_difference = hunk.file_length_difference

      next unless oldhunk
      next if LINES.positive? and hunk.merge(oldhunk)

      result << oldhunk.diff(FORMAT) << "\n"
    ensure
      oldhunk = hunk
    end
  end

  last = oldhunk.diff(FORMAT)
  last << "\n" if last.respond_to?(:end_with?) && !last.end_with?("\n")
  result << last
end

# File lib/cfndk/logger.rb, line 2
def self.logger
  @logger = CFnDKLogger.new({}) if @logger.nil?
  @logger
end

# File lib/cfndk/logger.rb, line 7
def self.logger=(logger)
  @logger = logger
end