class Cucumber::CucumberExpressions::Token

def self.can_escape(codepoint)
  c = codepoint.chr(Encoding::UTF_8)
  if c == ' '
    # TODO: Unicode whitespace?
    return true
  end
  case c
  when ESCAPE_CHARACTER
    true
  when ALTERNATION_CHARACTER
    true
  when BEGIN_PARAMETER_CHARACTER
    true
  when END_PARAMETER_CHARACTER
    true
  when BEGIN_OPTIONAL_CHARACTER
    true
  when END_OPTIONAL_CHARACTER
    true
  else
    false
  end
end

def self.is_escape_character(codepoint)
  codepoint.chr(Encoding::UTF_8) == ESCAPE_CHARACTER
end

def self.purpose_of(token)
  case token
  when TokenType::BEGIN_OPTIONAL
    return 'optional text'
  when TokenType::END_OPTIONAL
    return 'optional text'
  when TokenType::BEGIN_PARAMETER
    return 'a parameter'
  when TokenType::END_PARAMETER
    return 'a parameter'
  when TokenType::ALTERNATION
    return 'alternation'
  else
    return ''
  end
end

def self.symbol_of(token)
  case token
  when TokenType::BEGIN_OPTIONAL
    return BEGIN_OPTIONAL_CHARACTER
  when TokenType::END_OPTIONAL
    return END_OPTIONAL_CHARACTER
  when TokenType::BEGIN_PARAMETER
    return BEGIN_PARAMETER_CHARACTER
  when TokenType::END_PARAMETER
    return END_PARAMETER_CHARACTER
  when TokenType::ALTERNATION
    return ALTERNATION_CHARACTER
  else
    return ''
  end
end

def self.type_of(codepoint)
  c = codepoint.chr(Encoding::UTF_8)
  if c == ' '
    # TODO: Unicode whitespace?
    return TokenType::WHITE_SPACE
  end
  case c
  when ALTERNATION_CHARACTER
    TokenType::ALTERNATION
  when BEGIN_PARAMETER_CHARACTER
    TokenType::BEGIN_PARAMETER
  when END_PARAMETER_CHARACTER
    TokenType::END_PARAMETER
  when BEGIN_OPTIONAL_CHARACTER
    TokenType::BEGIN_OPTIONAL
  when END_OPTIONAL_CHARACTER
    TokenType::END_OPTIONAL
  else
    TokenType::TEXT
  end
end

def initialize(type, text, start, ending)
  @type, @text, @start, @end = type, text, start, ending
end

def to_hash
  {
    'type' => @type,
    'text' => @text,
    'start' => @start,
    'end' => @end
  }
end