gistfile1.txt

#Van's Cash Register

require 'date'
require 'time'

price = 0
items = []
sub_total = 0

def numeric?(object)
	object =~ /\A\$?\d+(\.\d{1,2})?\z/
end

while price != "done" do

	puts "Add a sale price"
	price = gets.chomp
	sub_total += price.to_f
	puts "Subtotal: $" + sprintf('%0.2f', sub_total.to_f)
	items<<price unless price == "done"
end

puts "Here are your items:"
	items.each do |i|
	puts "$" + i.to_s
end

puts "Total Amount Due is: " + sprintf('$%0.2f', sub_total.to_f)

puts "What is the amount tendered?"

amount_tendered = gets.chomp

if numeric?(amount_tendered)
	if  amount_tendered.to_f >= sub_total.to_f
		puts "===Thank You!==="
		puts "The total change due is #{sprintf('$%0.2f', (amount_tendered.to_f-sub_total.to_f))}"
		puts ""
		puts DateTime.now
	else
		puts "WARNING: Customer still owes #{sprintf('$%0.2f', (sub_total.to_f-amount_tendered.to_f))}! Exiting..."
	end
else
	puts "WARNING: Invalid currency detected! Exiting..."
end