class ElegantMoney

# File lib/elegant_money.rb, line 10
def self.configuration
  @configuration ||= Configuration.new
end

# File lib/elegant_money.rb, line 6
def self.configure
  yield configuration
end

# File lib/elegant_money.rb, line 14
def initialize(amount, currency = 'EUR')
  @amount = BigDecimal.new(amount.to_s)
  @currency = currency
end

# File lib/elegant_money.rb, line 41
def *(other)
  operate_with_normalized_currency(other) do |other_amount|
    amount * other_amount
  end
end

# File lib/elegant_money.rb, line 29
def +(other)
  operate_with_normalized_currency(other) do |other_amount|
    amount + other_amount
  end
end

# File lib/elegant_money.rb, line 35
def -(other)
  operate_with_normalized_currency(other) do |other_amount|
    amount - other_amount
  end
end

# File lib/elegant_money.rb, line 47
def /(other)
  operate_with_normalized_currency(other) do |other_amount|
    amount / other_amount
  end
end

# File lib/elegant_money.rb, line 24
def <=>(other)
  other_amount = amount_with_normalized_currency(other)
  amount.round(2) <=> other_amount.round(2)
end

# File lib/elegant_money.rb, line 53
def convert_to(new_currency)
  return build(amount, currency) if currency == new_currency

  conversion = conversion_for(new_currency)
  new_amount = if currency == default_currency
    amount * conversion
  else
    default_amount = amount / conversion_for(currency)
    default_amount * conversion
  end

  build(new_amount, new_currency)
end

# File lib/elegant_money.rb, line 67
def infinite?
  amount.infinite?
end

# File lib/elegant_money.rb, line 19
def inspect
  "%.2f %s" % [amount, currency]
end

# File lib/elegant_money.rb, line 78
def amount_with_normalized_currency(other)
  return other.convert_to(currency).amount if other.is_a?(ElegantMoney)
  return BigDecimal.new(other.to_s) if other.is_a?(Float)
  other
end

# File lib/elegant_money.rb, line 84
def build(amount, currency)
  ElegantMoney.new(amount, currency)
end

# File lib/elegant_money.rb, line 88
def conversion_for(key)
  return 1 if key == default_currency
  ElegantMoney.configuration.conversions.fetch(key)
end

# File lib/elegant_money.rb, line 93
def default_currency
  ElegantMoney.configuration.default_currency
end

# File lib/elegant_money.rb, line 73
def operate_with_normalized_currency(other)
  result = yield amount_with_normalized_currency(other)
  build(result, currency)
end