module Padrino::Helpers::NumberHelpers

# => 1234567890,50 £
number_to_currency(1234567890.50, :unit => "£", :separator => ",", :delimiter => "", :format => "%n %u")
# => £1234567890,50
number_to_currency(1234567890.50, :unit => "£", :separator => ",", :delimiter => "")

number_to_currency(1234567890.506, :precision => 3) # => $1,234,567,890.506
number_to_currency(1234567890.506) # => $1,234,567,890.51
number_to_currency(1234567890.50) # => $1,234,567,890.50

==== Examples

%n The number
%u The currency unit

:format:: Sets the format of the output string (defaults to "%u%n"). The field types are:
:delimiter:: Sets the thousands delimiter (defaults to ",").
:separator:: Sets the separator between the units (defaults to ".").
:unit:: Sets the denomination of the currency (defaults to "$").
:precision:: Sets the level of precision (defaults to 2).

==== Options

in the +options+ hash.
Formats a +number+ into a currency string (e.g., $13.65). You can customize the format
#

def number_to_currency(number, options = {})
  options.symbolize_keys!
  defaults  = I18n.translate(:'number.format', :locale => options[:locale], :raise => true) rescue {}
  currency  = I18n.translate(:'number.currency.format', :locale => options[:locale], :raise => true) rescue {}
  defaults  = defaults.merge(currency)
  precision = options[:precision] || defaults[:precision]
  unit      = options[:unit]      || defaults[:unit]
  separator = options[:separator] || defaults[:separator]
  delimiter = options[:delimiter] || defaults[:delimiter]
  format    = options[:format]    || defaults[:format]
  separator = '' if precision == 0
  begin
    format.gsub(/%n/, number_with_precision(number,
      :precision => precision,
      :delimiter => delimiter,
      :separator => separator)
    ).gsub(/%u/, unit)
  rescue
    number
  end
end