Poke Mart

/* 
 * The Pokemart
 *
 * This assignment has you working with Objects and Functions/Methods.
 * The goal is to create code to represent a pokemart that sells items, and then
 * simulate a player purchasing some items from the pokemart.
 * 
 * Requirements [READ CAREFULLY]:
 * The pokemart must be an Object containing at least 10 items. You can pick what
 * items are sold and at what price.
 * The player must have a predetermined amount of money, and must buy at least 20 items,
 * at least 3 of which must be unique (duplicates are allowed, make sure to give the player enough money).
 * Log how much money the player has to the console when the script starts.
 * Use an object to keep track of what is currently in the player's cart. Use functions/methods to add items to the cart.
 * Do NOT allow a player to have a negative number of an item in their cart.
 * Log when an item is added to the cart to the console, including the quantity.
 * The pokemart must have a checkout method to calculate how much money the player pays for the items.
 * The checkout method must log:
 * - A line for each item being purchased including the name of the item, quantity, and cost.
 * - A line for the total cost of the cart
 * - A line either saying how much money the player has left OR
 * - A line stating the player cannot afford the purchase
 * The checkout method must not allow a purchase that the player cannot afford.
 * OPTIONAL BONUS: Add an extra item that cannot be purchased but it can be obtained in a simaler way to premier balls in the pokemon games.
 * - If you do this, make sure this item cannot be added to the cart, and note how many were given (if > 0) after sucessfully checking out.
 * OPTIONAL BONUS 2: Make it so that the player can remove items from their cart. This can be a new function/method or built into
 * - the one for adding items to the cart (maybe a negative value indicates a removal?)
 * OPTIONAL BONUS 3: Empty the player's cart after they checkout (in the checkout function), and have them make a second purchase.
 * - (Second purchase only needs a total of 1 item and 1 unique item, unlike the first).
 * 
 * HINTS:
 * DRY (Don't repeat yourself)
 * Try to make your code industrial strength. This means verify function arguments before doing what was asked.
 * For example: When adding to cart, make sure the requested item is a valid item & can be purchased, also make sure
 * the player will not have a negative number of that item in their cart after (or just block negative values).
 * You can use the return keyword to terminate a function early, even if the return value is unimportant to the function.
 * Use Math.floor(NUMBER) to round NUMBER down to the nearest whole number (returns an integer).
 */
'use strict';

let pokemart = {
    pokeball: 200,
    greatball: 600,
    ultraball: 800,
    potion: 200,
    superpotion: 700,
    hyperpotion: 1500,
    maxpotion: 2500,
    fullrestore: 3000,
    revive: 2000,
    antidote: 200,
    paralyzeheal: 300,
    awakening: 100,
    burnheal: 300,
    iceheal: 100,
    fullheal: 400,
};

function calculateCost(objCost = 0, numObj = 0) {
    return (objCost * numObj);
}

// Starts out empty.
let cart = {};

// Adds a certain amount of an item to the cart, if the user has enough money.
function addToCart (item, quantity) {
    let totalCost = calculateCost(pokemart[item], quantity);

    if (totalCost + cartValue > startingWealth) {
        console.log(`You wouldn't have enough to buy that if you added it to your cart.`);
    } else {
        cartValue += totalCost;
        console.log(`You added ${quantity} ${item}${addPlural(quantity)} from your cart.`);
        console.log(`You have ${startingWealth - cartValue} Pokédollar${addPlural(startingWealth - cartValue)} to spend.\n`);
        // If it's already in the cart, add to what we have.
        if (cart[item] == undefined) {
            cart[item] = quantity;
        } else {
            cart[item] += quantity;
        }
    }
}

function showCart () {
    let found = false;
    for (let property in cart) {
        if (cart[property] > 0) {
            console.log(`${property.padStart(15, ' ')} x ` + cart[property]);
            found = true;
        }
    }
    if (!found)
        console.log(`  Your cart is empty.`);
}

/* Removes a certain amount or all of an item from the cart.  If we made it here,
 * we already verified that they are removing a real item and correct quantity.
 */
function removeFromCart (item, quantity) {
    let totalCost = calculateCost(pokemart[item], quantity);
    cartValue -= totalCost;
    console.log(`You removed ${quantity} ${item}${addPlural(quantity)} from your cart.`);
    console.log(`You have ${startingWealth - cartValue} Pokédollar${addPlural(startingWealth - cartValue)} to spend.\n`);

    // If it hits 0, then delete it.
    if (cart[item] == quantity) {
        delete cart[item];
    } else {
        cart[item] -= quantity;
    }
}

function addPlural(amount) {
    if (amount === 1)
        return "";
    else
        return "s";
}

// Starting amount of money.
let startingWealth = 20000;
let cartValue = 0;

let readline = require('readline');

let rl = readline.createInterface({
    input: process.stdin,
    output: process.stdout
})

// Lists the options available.
function showPrompt() {
    console.log(`     list: lists all items for sale` + 
        `\n      buy: adds items from the Mart to your cart. e.g. "buy 2 potion"` + 
        `\n   remove: removes items from your cart.  e.g. "remove 2 potion" or "remove all potion"` + 
        `\n     cart: shows the items in your cart` +
        `\n   wealth: shows how much money you have` +
        `\n checkout: buys everything in your cart` +
        `\n     done: closes out of the Poke Mart\n\nWhat would you like to do?`);
}

console.log(`Welcome to the Poke Mart! May I help you?`);
console.log(`You have ${startingWealth} Pokédollar${addPlural(startingWealth)} to spend.`);
console.log(`Your cart is currently worth ${cartValue} Pokédollar${addPlural(cartValue)}.`);
showPrompt();

rl.on('line', function (line) {
        /* Break up what the entered word for word.  This means the str[0] will
         * be the command they used, and str[1] and str[2] will be arguments
         * for buying and selling items.
         */
        let str = line.split(" ");
        let quantity = parseInt(str[1]);

        // 1) List all objects for sale.
        if (str[0] === "list") {
            console.log(`This is what we have for sale:`);
            for (let property in pokemart) {
                if (pokemart[property] >= 0)
                    console.log(`${property.padStart(15, ' ')}: ` + pokemart[property]);
            }
            console.log(`\nWhat would you like to do?`);

        // 2) Add an object to the cart if we have enough money.
        } else if (str[0] === "buy") {
            // Go through all the conditions where they failed their syntax.
            if (pokemart[str[2]] == undefined) {
                console.log(`We don't have any of that for sale.  Try checking our "list".`);
            } else if (isNaN(quantity)) {
                console.log(`You have to enter a number of that item to add to your cart!`);
            } else if (quantity < 1) {
                console.log(`You can't add less than 1 of that.`);
            } else {
                // If we made it to here, we try to add it to the cart.
                addToCart(str[2], quantity);
            }
            
        // 3) Remove an item from the cart.
        } else if (str[0] === "remove") {

            // Go through all the conditions where they failed their syntax.
            if (cart[str[2]] == undefined) {
                console.log(`You don't have that in your cart.  Try checking your "cart".`);
            } else {

                /* If they used "all" for the quantity, set it to the amount they
                 * have in their cart right now. */
                if (str[1] === "all")
                    quantity = cart[str[2]];

                if (isNaN(quantity)) {
                    console.log(`You have to enter a number of that item to remove from your cart!`);
                } else if (quantity > cart[str[2]]) {
                    console.log(`You can't remove more of that than you have.`);
                } else if (quantity < 1) {
                    console.log(`You can't remove less than 1 of that.`);
                } else {
                    // If we made it to here, we try to remove it from the cart.
                    removeFromCart(str[2], quantity);
                }
            }

        // 4) List current items in the cart.
        } else if (str[0] === "cart") {
            console.log(`This is what you have in your cart:`);
            showCart();
            console.log(`Your cart is currently worth ${cartValue} Pokédollar${addPlural(cartValue)}.\n`);

        // 5) Check how much money we have.
        } else if (str[0] === "wealth") {
            console.log(`You have ${startingWealth} Pokédollar${addPlural(startingWealth)} to spend.`);
            console.log(`Your cart is currently worth ${cartValue} Pokédollar${addPlural(cartValue)}.`);

        // 6) Checkout items in cart.
        } else if (str[0] === "checkout") {
            if (cartValue <= 0) {
                console.log(`You have nothing to check out.`);
            } else {
                showCart();
                console.log(`You spent a total of ${cartValue} Pokédollar${addPlural(cartValue)}.  Thanks for your purchase!`);
                
                // They get 1 premierball for every 10 pokeballs.
                if (cart["pokeball"] >= 10) {
                    let bonusBalls = Math.floor(cart["pokeball"] / 10);
                    console.log(`You also get ${bonusBalls} premierball${addPlural(bonusBalls)} as an added bonus.`);
                }

                // Spend their money and empty their cart.
                startingWealth -= cartValue;
                cartValue = 0;
                cart = {};
                console.log(`You have ${startingWealth} Pokédollar${addPlural(startingWealth)} left to spend.\n`);
            }

        // 7) Finish up and leave.
        } else if (str[0] === "done") {
            console.log(`Please come again!`);
            rl.close();

        // They entered a command we don't understand.
        } else {
            console.log(`I didn't quite catch that.  How can I help you?`);
            showPrompt();
        }

});