class Money::FormattingRules

def [](key)
  @rules[key]
end

def default_formatting_rules
  Money.default_formatting_rules || {}
end

def delimiter_pattern_rule(rules)
  if rules[:south_asian_number_formatting]
    # from http://blog.revathskumar.com/2014/11/regex-comma-seperated-indian-currency-format.html
    /(\d+?)(?=(\d\d)+(\d)(?!\d))(\.\d+)?/
  else
    /(\d)(?=(?:\d{3})+(?:[^\d]{1}|$))/
  end
end

def determine_format_from_formatting_rules(rules)
  return currency.format if currency.format && !rules.has_key?(:symbol_position)
  symbol_position = symbol_position_from(rules)
  if symbol_position == :before
    rules.fetch(:symbol_before_without_space, true) ? '%u%n' : '%u %n'
  else
    rules[:symbol_after_without_space] ? '%n%u' : '%n %u'
  end
end

def has_key?(key)
  @rules.has_key? key
end

def initialize(currency, *raw_rules)
  @currency = currency
  # support for old format parameters
  @rules = normalize_formatting_rules(raw_rules)
  @rules = default_formatting_rules.merge(@rules) unless @rules[:ignore_defaults]
  @rules = localize_formatting_rules(@rules)
  @rules = translate_formatting_rules(@rules) if @rules[:translate]
  @rules[:format] ||= determine_format_from_formatting_rules(@rules)
  @rules[:delimiter_pattern] ||= delimiter_pattern_rule(@rules)
  warn_about_deprecated_rules(@rules)
end

def localize_formatting_rules(rules)
  if currency.iso_code == "JPY" && I18n.locale == :ja
    rules[:symbol] = "円" unless rules[:symbol] == false
    rules[:format] = '%n%u'
  end
  rules
end

def normalize_formatting_rules(rules)
  if rules.size == 0
    rules = {}
  elsif rules.size == 1
    rules = rules.pop
    rules = rules.dup if rules.is_a?(Hash)
    if rules.is_a?(Symbol)
      warn '[DEPRECATION] Use Hash when passing rules to Money#format.'
      rules = { rules => true }
    end
  end
  if !rules.include?(:decimal_mark) && rules.include?(:separator)
    rules[:decimal_mark] = rules[:separator]
  end
  if !rules.include?(:thousands_separator) && rules.include?(:delimiter)
    rules[:thousands_separator] = rules[:delimiter]
  end
  rules
end

def symbol_position_from(rules)
  if rules.has_key?(:symbol_position)
    if [:before, :after].include?(rules[:symbol_position])
      return rules[:symbol_position]
    else
      raise ArgumentError, ":symbol_position must be ':before' or ':after'"
    end
  elsif currency.symbol_first?
    :before
  else
    :after
  end
end

def translate_formatting_rules(rules)
  begin
    rules[:symbol] = I18n.t currency.iso_code, scope: "number.currency.symbol", raise: true
  rescue I18n::MissingTranslationData
    # Do nothing
  end
  rules
end

def warn_about_deprecated_rules(rules)
  if rules.has_key?(:symbol_position)
    position = rules[:symbol_position]
    template = position == :before ? '%u %n' : '%n %u'
    warn "[DEPRECATION] `symbol_position: :#{position}` is deprecated - you can replace it with `format: #{template}`"
  end
  if rules.has_key?(:symbol_before_without_space)
    warn "[DEPRECATION] `symbol_before_without_space:` option is deprecated - you can replace it with `format: '%u%n'`"
  end
  if rules.has_key?(:symbol_after_without_space)
    warn "[DEPRECATION] `symbol_after_without_space:` option is deprecated - you can replace it with `format: '%n%u'`"
  end
  if rules.has_key?(:html)
    warn "[DEPRECATION] `html` is deprecated - use `html_wrap` instead. Please note that `html_wrap` will wrap all parts of currency and if you use `with_currency` option, currency element class changes from `currency` to `money-currency`."
  end
  if rules.has_key?(:html_wrap_symbol)
    warn "[DEPRECATION] `html_wrap_symbol` is deprecated - use `html_wrap` instead. Please note that `html_wrap` will wrap all parts of currency."
  end
end