instacart.rb

# Welcome the user
# Display the stock/list of products
# Get user choice
# ask quantity
# save quantity
# Check if it's available
# Add to cart
# Ask if they want continue shoppinh
# Add total and display bill

def calculate_total(cart)
  # total = 0
# CART.each { |_key, value| total += value }
  cart.reduce(0) { |total, (item, quantity)| total += quantity * STORE[item] }
end

STORE = {
  "kiwi" => 1.25,
  "banana" => 0.50,
  "mango" => 4.00,
  "aspargus" => 9.00
}

CART = {}

puts "Welcome to Instacart"
puts "********************"
puts "\n\n" # \n added a new line

STORE.each do |item, value|
  # sprintf "%.2f", value  <==> sprintf("%.2f", value)
  puts "#{item}: #{sprintf "%.2f", value} €"
end

loop do
  puts "Which item? (or 'quit' to checkout)"
  choice = gets.chomp

  break if choice == "quit"

  if STORE.key?(choice)
    puts "How many?"
    quantity = gets.chomp

    until quantity.match(/\d/)
      puts "Please type a valid amount"
      quantity = gets.chomp
    end

    # CART[choice] = STORE[choice] # e.g. STORE['kiwi'] => 1.25
    CART[choice] = quantity.to_i
  else
    puts "Sorry, we don't have #{choice} today."
  end
end

# Checkout
puts "-------BILL---------"
puts "Item | Amount | Cost"
CART.each do |item, quantity|
  puts "#{item} x #{quantity} : #{sprintf "%.2f", quantity * STORE[item]} €"
end
puts "TOTAL: #{calculate_total(CART)} €"
puts "--------------------"
puts "Thank you for shopping"