class Sass::Script::Value::String

def self.quote(contents, opts = {})
  quote = opts[:quote]
  # Short-circuit if there are no characters that need quoting.
  unless contents =~ /[\n\\"']|\#\{/
    quote ||= '"'
    return "#{quote}#{contents}#{quote}"
  end
  if quote.nil?
    if contents.include?('"')
      if contents.include?("'")
        quote = '"'
      else
        quote = "'"
      end
    else
      quote = '"'
    end
  end
  # Replace single backslashes with multiples.
  contents = contents.gsub("\\", "\\\\\\\\")
  # Escape interpolation.
  contents = contents.gsub('#{', "\\\#{") if opts[:sass]
  if quote == '"'
    contents = contents.gsub('"', "\\\"")
  else
    contents = contents.gsub("'", "\\'")
  end
  contents = contents.gsub(/\n(?![a-fA-F0-9\s])/, "\\a").gsub("\n", "\\a ")
  "#{quote}#{contents}#{quote}"
end

def self.value(contents)
  contents.gsub("\\\n", "").gsub(/\\(?:([0-9a-fA-F]{1,6})\s?|(.))/) do
    next $2 if $2
    # Handle unicode escapes as per CSS Syntax Level 3 section 4.3.8.
    code_point = $1.to_i(16)
    if code_point == 0 || code_point > 0x10FFFF ||
        (code_point >= 0xD800 && code_point <= 0xDFFF)
      '�'
    else
      [code_point].pack("U")
    end
  end
end

def check_deprecated_interp
  return unless @deprecated_interp_equivalent
  @@interpolation_deprecation.warn(source_range.file, source_range.start_pos.line, <<WARNING)
 interpolation near operators will be simplified in a future version of Sass.
reserve the current behavior, use quotes:
@deprecated_interp_equivalent}
ING
end

def initialize(value, type = :identifier, deprecated_interp_equivalent = nil)
  super(value)
  @type = type
  @deprecated_interp_equivalent = deprecated_interp_equivalent
end

def inspect
  String.quote(value)
end

def plus(other)
  other_value = if other.is_a?(Sass::Script::Value::String)
                  other.value
                else
                  other.to_s(:quote => :none)
                end
  Sass::Script::Value::String.new(value + other_value, type)
end

def separator
  check_deprecated_interp
  super
end

def to_a
  check_deprecated_interp
  super
end

def to_s(opts = {})
  return @value.gsub(/\n\s*/, ' ') if opts[:quote] == :none || @type == :identifier
  String.quote(value, opts)
end

def to_sass(opts = {})
  to_s(opts.merge(:sass => true))
end