Ruby Fundamentals III - Challenge

ruby_fund_3.rb

# Ruby Fundamentals III - Challenge

#  NOTE:  I worked on this with Jonah and then refactored on my own.

# METHOD DEFINITIONS

def get_input(prompt)
  puts prompt
  input = gets.chomp.to_f
end

def validate_input(input, regex, error_message)
  while input.to_s.match(regex)
    puts error_message
    input = gets.chomp.to_i
  end
  input
end

def valid?(price)
  if price.match(/\A\d+(\.\d{0,2})?\z/)
    true
  end
end

def calc_subtotals(array)
 array.each do |hash|
   hash[:subtotal] = hash[:quantity] * hash[:price]
 end
end

def total(array)
 array = calc_subtotals(array)
 products = []
 array.each {|hash| products << hash[:subtotal]}
 products.inject(0) {|total, num| total + num}
end

# INITIALIZED VARIABLES

sales = [{type: "Light", price: 5.00, quantity: 0, subtotal: 0},
       {type: "Medium", price: 7.50, quantity: 0, subtotal: 0},
       {type: "Bold",   price: 9.75, quantity: 0, subtotal: 0}]

# PROGRAM

puts "Welcome to James' coffee emporium!\n\n"
puts "1) Add item - $5.00 - Light Bag"
puts "2) Add item - $7.50 - Medium Bag"
puts "3) Add item - $9.75 - Bold Bag"
puts "4) Complete Sale\n\n"

  # PART 1: gets input (items & quantity sold), puts subtotal

while true
  selection = get_input("Make a selection:").to_i
  selection = validate_input(selection, /[^1-4]/, "Please enter a selection 1 through 4.")
  break if selection == 4

  quantity = get_input("How many bags:").to_i
  quantity = validate_input(quantity, /\D/, "Please enter a number.")

  sales[selection - 1][:quantity] += quantity
  subtotal = total(sales)
  puts "Subtotal: $#{sprintf("%.2f", subtotal)}\n\n"
end

if total(sales) == 0
  puts "You did not sell anything.  Goodbye!"
  exit
end

  # PART 2:  when finished adding sales, output subtotals & total due

puts "\n===Sale Complete===\n\n"

sales.each do |item|
  puts "$#{sprintf("%.2f", item[:subtotal])} - #{item[:quantity]} #{item[:type]}\n" unless item[:subtotal] == 0
end
puts "\nTotal: $#{sprintf("%.2f", subtotal)}\n\n"

  # PART 3:  calculates change

amount_due = subtotal
amount_tendered = get_input("What is the amount tendered?")
if valid?(amount_tendered.to_s)
  amount_tendered = amount_tendered.to_f
else
  puts "WARNING: Invalid currency detected! Exiting..."
  abort
end

total_change_due = amount_tendered - amount_due
total_change_due_formatted = sprintf("%.2f", total_change_due.abs)

if total_change_due >= 0
  current_time = Time.now.strftime("%m/%d/%Y %l:%M %p")
  puts "\n===Thank You!==="
  puts "The total change due is $#{total_change_due_formatted}"
  puts
  puts "#{current_time}"
  puts "================"
else
  puts "WARNING: Customer still owes $#{total_change_due_formatted}! Exiting..."
  abort
end

I've run this program a few times, and I think Part 3 doesn't correctly calculate change when the amount due isn't a whole dollar value. If I buy 2 of each item, the subtotal is $66.75, but then if the customer pays $66.75, it says the customer still owes $0.75.

On the other hand, the functions at the top are beautiful. Yay for pair refactoring! It's really nice to see how others approached the same problem.

Thanks! I updated it so it works. (I was converting the input I got in my get_input method to an integer, which rounded down the amount_tendered. I changed my get_input method to return a float, and then converted selection & quantity to_i when I called get_input on lines 56 & 60.)