module Kakimasu
  module Generators
    class RestoreBackupGenerator < Rails::Generators::Base
      backup_file = '.kakimasu_backup.yml'

      # Checks if there is backup file
      unless File.file?(backup_file)
        puts '**************************'
        puts "Backup file can't be found"
        puts '**************************'

      else
        # Reads content of backup file
        backup_file_content = File.read(backup_file)

        locale = nil           # Used to store locale for a temporary time
        key_parts = []         # Used to store parts of the 'lazy lookup' key, to at the end join them in one key
        lazy_lookup = false    # Determines if key is lazy lookup

        # Read backup file by lines
        backup_file_content.each_line do |line|

          # Every line with translation starts with spaces
          if line.start_with?('  ')
            # Gets level of the key and gets translation

            # Check if it is first level key
            if line.match /^\s\s[\w]+[:]\s["][^"]+["]/
              # Get translation key and translation from the line
              translation_key = line.scan(/^\s\s([\w]+)[:]\s["][^"]+["]/).first.first
              translation = line.scan(/^\s\s[\w]+[:]\s["]([^"]+)["]/).first.first

              # empty 'lazy lookup' key parts array because this means that lazy lookup key is done even if there was no translation (That means it has no translation)
              key_parts = []
              lazy_lookup = false

            # If its not first level translation, then it means that this is 'lazy lookup' translation
            else
              lazy_lookup = true

              # If line has no translation, just key, then it is part of 'lazy lookup' key
              if line.match /\w+[:]$/
                key_parts.push line.scan(/(\w+)[:]$/).first.first    # Gets 'lazy lookup' key part from the line and pushes it into array

              # If key has translation then it is last part of 'lazy lookup' key
              elsif line.match /\w+[:]\s["]([^"]+)["]/
                # Gets 'lazy lookup' keys last part and gets translation
                key_parts.push line.scan(/(\w+)[:]\s["][^"]+["]/).first.first
                translation = line.scan(/\w+[:]\s["]([^"]+)["]/).first.first
              end
            end

          # lines with no spaces in start is just for locales or blank lines
          else
            # If line is not meant as blank line, then it's locale and function gets locale from it
            locale = line.partition(':').first unless line.start_with?("\n")
          end

          # If 'lazy lookup' key then save it as 'lazy lookup' key otherwise save it like not 'lazy lookup key'
          if lazy_lookup && translation
            # Form 'lazy lookup' key
            translation_key = key_parts.join('.')

            # Store translation
            I18n.backend.store_translations(locale, {translation_key => translation}, escape: false)

            # Set back variables
            key_parts = []
            translation = nil
            translation_key = nil

          elsif translation_key && translation
            # Store translation
            I18n.backend.store_translations(locale, {translation_key => translation}, escape: false)

            # Set back variables
            translation = nil
            translation_key = nil
          end
        end

        # Message about successfull translation restore from backup file
        puts '***********************************'
        puts 'Translations successfully restored!'
        puts '***********************************'
      end
    end
  end
end