module FixtureFox
  class Token
    attr_reader :file
    attr_reader :lineno
    attr_reader :initial_indent
    attr_reader :pos
    attr_reader :litt
    attr_reader :value

    def initialize(file, lineno, initial_indent, pos, litt)
      @file, @lineno, @initial_indent, @pos, @litt = file, lineno, initial_indent, pos, litt
      @value = @litt
    end

    def ==(s) @litt == s end
    def to_s() @litt end

    def error(msg)
      raise ParseError.new(file, lineno, initial_indent + pos, msg)
    end
  end

  class AnchorToken < Token
    def initialize(file, lineno, initial_indent, pos, litt)
      super
      @value = litt[1..-1].to_sym
    end

    # Convert an Ident token to a AnchorToken token
    def self.of_ident(ident)
      AnchorToken.new(ident.file, ident.lineno, ident.initial_indent, ident.pos, "&#{ident.litt}")
    end
  end

  class Empty < Token
  end

  class Directive < Token
    def initialize(file, lineno, initial_indent, pos, litt)
      super
      @value = litt[1..-1]
    end
  end

  class Ident < Token
  end

  class Reference < Token
#   attr_reader :reference
    def initialize(file, lineno, initial_indent, pos, litt)
      super
      @value = litt[1..-1]
    end
  end

  class Value < Token
    attr_reader :klass # NilClass, TrueClass, Integer, Float, String, Array

    def initialize(file, lineno, initial_indent, pos, litt)
      super

      i = 1
      case litt
        when /^(nil)/, /^(null)/
          i += $1.size
          @klass = NilClass
          @value = nil

        when /^(true)/, /^(false)/
          i += $1.size
          @klass = TrueClass
          @value = ($1 == "true")

        when /^([-+]?\d+\.\d+)/
          i += $1.size
          @klass = Float
          @value = $1.to_f

        when /^([-+]?\d+)/
          i += $1.size
          @klass = Integer
          @value = $1.to_i

        when /^"/
          @value = ""
          @klass = String
          loop do
            i < litt.size or self.error("Unterminated string")
            if litt[i] == "\\"
              if litt[i+1] == "\\"
                @value += "\\"
                i += 2
              elsif litt[i+1] == '"'
                @value += '"'
                i += 2
              elsif litt[i+1] == 'n'
                @value += "\n"
                i += 2
              elsif litt[i+1] == 't'
                @value += "\t"
                i += 2
              else
                @value += "\\"
                i += 1
              end
            elsif litt[i] == '"'
              i += 1
              break
            else
              @value += litt[i]
              i += 1
            end
          end

        when /^'/
          @value = ""
          @klass = String
          loop do
            i < litt.size or self.error("Unterminated string")
            if litt[i] == "'"
              if litt[i+1] == "'"
                @value += "'"
                i += 2
              else
                i += 1
                break
              end
            else
              @value += litt[i]
              i += 1
            end
          end

        # Inline arrays are split on ',' and on blanks. '\' is the escape
        # character
        #
        # FIXME: Quotes doesn't override separator. Eg. this throws an
        # exception: ['hello world']
        when /^(\[\s*)(.*)\]$/
          i += $1.size
          elements = $2
          matches = elements.split(/(\s*(?<!(?<!\\{2})\\)[, ]\s*)/)

          @value = []
          while element = matches.shift
            unescaped_element = element.gsub(/\\/, "")
            @value << Value.new(file, lineno, initial_indent, i, unescaped_element).value
            i += element.size + (matches.shift&.size || 0)
          end
          @klass = Array

        when /^\{/
          i += litt.size
          @value = HashParser.parse(litt)
          @klass = Hash

        else
          i += litt.size
          @klass = String
          @value = litt.dup
      end

      (litt[i..-1] || "") =~ /^\s*(?:#.*)?$/ or self.error("Illegal characters after literal")
    end

    def to_s()
      if klass == NilClass
        "null"
#     elsif klass == String
#       "'#{value.gsub("'", "''")}'"
      else
        value.to_s
      end
    end
  end

end