class RuboCop::ProcessedSource

def self.from_file(path, ruby_version)
  file = File.read(path, mode: 'rb')
  new(file, ruby_version, path)
rescue Errno::ENOENT
  raise RuboCop::Error, "No such file or directory: #{path}"
end

def [](*args)
  lines[*args]
end

def ast_with_comments
  return if !ast || !comments
  @ast_with_comments ||= Parser::Source::Comment.associate(ast, comments)
end

def checksum
  Digest::MD5.hexdigest(@raw_source)
end

def comment_config
  @comment_config ||= CommentConfig.new(self)
end

def create_parser(ruby_version)
  builder = RuboCop::Node::Builder.new
  parser_class(ruby_version).new(builder).tap do |parser|
    # On JRuby and Rubinius, there's a risk that we hang in tokenize() if we
    # don't set the all errors as fatal flag. The problem is caused by a bug
    # in Racc that is discussed in issue #93 of the whitequark/parser
    # project on GitHub.
    parser.diagnostics.all_errors_are_fatal = (RUBY_ENGINE != 'ruby')
    parser.diagnostics.ignore_warnings = false
    parser.diagnostics.consumer = lambda do |diagnostic|
      @diagnostics << diagnostic
    end
  end
end

def disabled_line_ranges
  comment_config.cop_disabled_line_ranges
end

def initialize(source, ruby_version, path = nil)
  # Defaults source encoding to UTF-8, regardless of the encoding it has
  # been read with, which could be non-utf8 depending on the default
  # external encoding.
  unless source.encoding == Encoding::UTF_8
    source.force_encoding(Encoding::UTF_8)
  end
  @raw_source = source
  @path = path
  @diagnostics = []
  @ruby_version = ruby_version
  parse(source, ruby_version)
end

def lines
  @lines ||= begin
    all_lines = @buffer.source_lines
    last_token_line = tokens.any? ? tokens.last.pos.line : all_lines.size
    result = []
    all_lines.each_with_index do |line, ix|
      break if ix >= last_token_line && line == '__END__'
      result << line
    end
    result
  end
end

def parse(source, ruby_version)
  buffer_name = @path || STRING_SOURCE_NAME
  @buffer = Parser::Source::Buffer.new(buffer_name, 1)
  begin
    @buffer.source = source
  rescue EncodingError => error
    @parser_error = error
    return
  end
  @ast, @comments, @tokens = tokenize(create_parser(ruby_version))
end

def parser_class(ruby_version) # rubocop:disable Metrics/MethodLength
  case ruby_version
  when 1.9
    require 'parser/ruby19'
    Parser::Ruby19
  when 2.0
    require 'parser/ruby20'
    Parser::Ruby20
  when 2.1
    require 'parser/ruby21'
    Parser::Ruby21
  when 2.2
    require 'parser/ruby22'
    Parser::Ruby22
  when 2.3
    require 'parser/ruby23'
    Parser::Ruby23
  when 2.4
    require 'parser/ruby24'
    Parser::Ruby24
  else
    raise ArgumentError, "Unknown Ruby version: #{ruby_version.inspect}"
  end
end

def tokenize(parser)
  begin
    ast, comments, tokens = parser.tokenize(@buffer)
    ast.complete! if ast
  rescue Parser::SyntaxError # rubocop:disable Lint/HandleExceptions
    # All errors are in diagnostics. No need to handle exception.
  end
  tokens = tokens.map { |t| Token.from_parser_token(t) } if tokens
  [ast, comments, tokens]
end

def valid_syntax?
  return false if @parser_error
  @diagnostics.none? { |d| [:error, :fatal].include?(d.level) }
end