module RuboCop::Cop::Util

def begins_its_line?(range)
  (range.source_line =~ /\S/) == range.column
end

def block_length(block_node)
  block_node.loc.end.line - block_node.loc.begin.line
end

def comment_line?(line_source)
  line_source =~ /^\s*#/
end

def directions(side)
  if side == :both
    [true, true]
  else
    [side == :left, side == :right]
  end
end

def double_quotes_acceptable?(string)
  # If a string literal contains hard-to-type characters which would
  # not appear on a "normal" keyboard, then double-quotes are acceptable
  needs_escaping?(string) ||
    string.codepoints.any? { |cp| cp < 32 || cp > 126 }
end

def double_quotes_required?(string)
  # Double quotes are required for strings which either:
  # - Contain single quotes
  # - Contain non-printable characters, which must use an escape
  # Regex matches IF there is a ' or there is a \\ in the string that is
  # not preceded/followed by another \\ (e.g. "\\x34") but not "\\\\".
  string =~ /'|(?<! \\) \\{2}* \\ (?![\\"])/x
end

def effective_column(range)
  if range.line == 1 &&
     @processed_source.raw_source.codepoints.first == BYTE_ORDER_MARK
    range.column - 1
  else
    range.column
  end
end

def ends_its_line?(range)
  line = range.source_buffer.source_line(range.last_line)
  (line =~ /\s*\z/) == range.last_column
end

def escape_string(string)
  string.inspect[1..-2].tap { |s| s.gsub!(/\\"/, '"') }
end

def first_part_of_call_chain(node)
  while node
    case node.type
    when :send
      receiver, _method_name, _args = *node
      node = receiver
    when :block
      method, _args, _body = *node
      node = method
    else
      break
    end
  end
  node
end

def interpret_string_escapes(string)
  StringInterpreter.interpret(string)
end

def line_range(arg)
  source_range = case arg
                 when Parser::Source::Range
                   arg
                 when Parser::AST::Node
                   arg.source_range
                 else
                   raise ArgumentError, "Invalid argument #{arg}"
                 end
  source_range.begin.line..source_range.end.line
end

def move_pos(src, pos, step, condition, regexp)
  offset = step == -1 ? -1 : 0
  pos += step while condition && src[pos + offset] =~ regexp
  pos
end

def needs_escaping?(string)
  double_quotes_required?(escape_string(string))
end

def numeric_range_size(range)
  size = range.end - range.begin
  size += 1 unless range.exclude_end?
  size = 0 if size < 0
  size
end

def on_node(syms, sexp, excludes = [], &block)
  return to_enum(:on_node, syms, sexp, excludes) unless block_given?
  yield sexp if Array(syms).include?(sexp.type)
  return if Array(excludes).include?(sexp.type)
  sexp.children.each do |elem|
    next unless elem.is_a?(Parser::AST::Node)
    on_node(syms, elem, excludes, &block)
  end
end

def operator?(symbol)
  OPERATOR_METHODS.include?(symbol)
end

def parentheses?(node)
  node.loc.respond_to?(:end) && node.loc.end &&
    node.loc.end.is?(')'.freeze)
end

def parenthesized_call?(send)
  send.loc.begin && send.loc.begin.is?('(')
end

def range_with_surrounding_comma(range, side = :both)
  buffer = @processed_source.buffer
  src = buffer.source
  go_left, go_right = directions(side)
  begin_pos = range.begin_pos
  end_pos = range.end_pos
  begin_pos = move_pos(src, begin_pos, -1, go_left, /,/)
  end_pos = move_pos(src, end_pos, 1, go_right, /,/)
  Parser::Source::Range.new(buffer, begin_pos, end_pos)
end

def range_with_surrounding_space(range, side = :both, with_newline = true)
  buffer = @processed_source.buffer
  src = buffer.source
  go_left, go_right = directions(side)
  begin_pos = range.begin_pos
  end_pos = range.end_pos
  begin_pos = move_pos(src, begin_pos, -1, go_left, /[ \t]/)
  begin_pos = move_pos(src, begin_pos, -1, go_left && with_newline, /\n/)
  end_pos = move_pos(src, end_pos, 1, go_right, /[ \t]/)
  end_pos = move_pos(src, end_pos, 1, go_right && with_newline, /\n/)
  Parser::Source::Range.new(buffer, begin_pos, end_pos)
end

def source_range(source_buffer, line_number, column, length = 1)
  if column.is_a?(Range)
    column_index = column.begin
    length = numeric_range_size(column)
  else
    column_index = column
  end
  line_begin_pos = if line_number == 0
                     0
                   else
                     source_buffer.line_range(line_number).begin_pos
                   end
  begin_pos = line_begin_pos + column_index
  end_pos = begin_pos + length
  Parser::Source::Range.new(source_buffer, begin_pos, end_pos)
end

def strip_quotes(str)
  if str[0] == '"' || str[0] == "'"
    str[0] = ''
  else
    # we're dealing with %q or %Q
    str[0, 3] = ''
  end
  str[-1] = ''
  str
end

def to_string_literal(string)
  if needs_escaping?(string)
    string.inspect
  else
    "'#{string.gsub('\\') { '\\\\' }}'"
  end
end

def to_symbol_literal(string)
  ":#{string.to_sym}"
end

def within_node?(inner, outer)
  o = outer.is_a?(Node) ? outer.source_range : outer
  i = inner.is_a?(Node) ? inner.source_range : inner
  i.begin_pos >= o.begin_pos && i.end_pos <= o.end_pos
end