ShoppingCart.module

<?php

class ShoppingCart extends WireData implements Module, ConfigurableModule
{

	public static function getModuleInfo()
	{
		return array(
			'title' => 'Shopping Cart',
			'version' => 101,
			'summary' => 'Simple shopping cart for PW',
			'singular' => true,
			'autoload' => true
		);
	}

	static public function getDefaultData() {
	   return array(
		   'allowNegativeStock' => 1,
		   'currencyBefore' => 0,
		   'currency' => '&euro;',
		   'currencyCode' => 'EUR',
		   'decimals' => 2,
		   'dec_point' => ',',
		   'thousands_sep' => ''
		   );
	}

	public function __construct() {
	   foreach(self::getDefaultData() as $key => $value) {
		   $this->$key = $value;
	   }
	}

	public function init() {
	}

	public function ready() {
		if ($this->input->post->sc_product_id) {
			$product_id = (int) $this->input->post->sc_product_id;
			$qty = (int) $this->input->post->sc_qty;
			$this->addProductToCart($this->pages->get($product_id), $qty);
			$this->session->redirect("./");
		}

		if ($this->input->post->sc_update) {
			$this->updateCart($this->input->post->items);
			$this->session->redirect("./");
		}

		if ($this->input->get->sc_remove) {
			$product_id = (int) $this->input->get->sc_remove;
			$product = $this->pages->get($product_id);
			$this->addProductToCart($product, 0);
			$this->session->redirect("./");
		}

		if ($this->input->post->sc_checkout) {
			$this->updateCart($this->input->post->items);
			$checkout = $this->pages->get("template=sc-checkout, include=hidden");
			if ($checkout->url)
				$this->session->redirect($checkout->url);
			else
				$this->session->redirect("./");
		}

	}


	/**
	 * Returns the default markup for "Add to cart form"
	 *
	 * @param Page $product Actual product page (usually just $page on your template)
	 * @param string $postUrl Url where we post (you can think that as a redirect, since post are handled by this autoload module)
	 * @return string|false Markup for "Add to cart form" or false if there ain't numeric and over 0 price for the product
	 *
	 */
	public function renderAddToCart(Page $product = NULL, $postUrl = "./")
	{
		if (is_null($product))
			$product = wire('page');

		if (!(is_numeric($product->sc_price)) || $product->sc_price <= 0)
			return false;

		if(!$this->allowNegativeStock && $product->sc_qty < 1) {
			return $this->_("Sorry, we are out of stock.");
		}


		$out = "<form method='post' action='$postUrl'>";
		$out .= "<input type='hidden' value='{$product->id}' name='sc_product_id' />";
		$out .= "<input type='number' name='sc_qty' value='1'/>";
		$out .= "<input type='submit' value='" . $this->_("Add to cart") . "' />";
		$out .= "</form>";



		return $out;
	}

	/**
	 * Returns true|false depending if product was added succesfully to the cart
	 *
	 * @param Page $product Actual product page
	 * @param int $qty How many items added, use 0 if you want to remove the item
	 * @return true|false
	 *
	 */
	public function ___addProductToCart(Page $product, $qty = 1)
	{
		$qty   = (int) $qty;

		if ($qty < 0)
			return false;

		if (!$this->checkStock($product, $qty)) {
			$errormsg = sprintf($this->_n("Sorry, we have only %d item left. Try again, please.", "Sorry, we have only %d items left. Try again, please.", $product->sc_qty), $product->sc_qty);
			$this->session->error($errormsg);
			return false;
		}

		$items = $this->getCurrentCart();

		// There is not a single product available
		if (count($items) == 0) {
			if ($qty > 0)
				$items[] = $this->_newItem($product->id, $qty);
		} else {
			$product_found = false;
			foreach ($items as $key => $item) {

				// There is already this product on cart
				if ($item->product_id === $product->id) {

					// We'll check if we have enough stock for this new quantity
					$newQty = $item->qty + $qty;
					$newQty = $this->checkStockAndReturnMaxQty($product, $newQty);
					$item->qty = $newQty;

					// If zero qty added, remove from basket
					if ($qty === 0) {
						unset($items[$key]);
						$items = array_values($items);
					}

					$product_found = true;
					break;
				}
			}

			if (!$product_found) {
				if ($qty > 0)
					$items[] = $this->_newItem($product->id, $qty);
			}
		}

		$total_sum = $this->getTotalSumFromItems($items);
		$items     = json_encode($items);

		// Update cart to db or insert new row if there isn't
		$update = $this->db->query("INSERT INTO {$this->className} SET items = '$items', total_sum = $total_sum, session_id = '" . $this->getSession() . "' ON DUPLICATE KEY UPDATE items = '$items', total_sum = $total_sum");

		return true;
	}

	/*
	 * Returns true if it is ok to add product to basket
	 *
	 * @param Page $product
	 * @param Integer $qty
	 *
	 */
	public function checkStock(Page $product, $qty) {
		$qty = (int) $qty;
		// If product have stock quantity, then we might be interested in that
		if ($product->sc_qty != '') {
			// Let's see if we don't allow negative stock and we are trying to
			// add more products than we have in stock
			if(!$this->allowNegativeStock && $qty > $product->sc_qty) {
				return false;
			}
		}
		return true;
	}

	/**
	 * Returns markup for actual cart, where is possibilities to edit and remove products and qty
	 *
	 * @return string markup for cart
	 *
	 */
	public function renderCart($viewOnly = false, ShippingAbstract $shippingModule = NULL)
	{
		$out = '';

		$items = $this->getCurrentCart();

		if (count($items) == 0) {
			return $this->_("No items in cart");
		}

		$total_sum = $this->getTotalSumFromItems($items, $shippingModule);

		if (!$viewOnly) $out .= "<form method='post' action='./'>";
		$out .= "<table>";
		$out .= "<tr><th>" . $this->_('Product') . "</th>";
		$out .= "<th>" . $this->_('Quantity') . "</th>";
		$out .= "<th>" . $this->_('Subtotal') . "</th>";
		if (!$viewOnly) $out .= "<th>" . $this->_('Remove?') . "</th>";
		$out .= "</tr>";

		foreach ($items as $item) {

			$total_price = $this->getProductPriceTotal($item);

			$product = $this->pages->get((int) $item->product_id);

			// If the product is repeater, let's prepend the product title before variation
			if (strpos($product->template->name, "repeater_") === 0) {
				$parentProduct = $product->getForPage();
				$title = $parentProduct->title . ": " . $product->title;
			} else {
				$title = $product->title;
			}

			$out .= "<tr>";
			$out .= "<td>{$title}</td>";
			if (!$viewOnly)	{
				$out .= "<td><input data-price='" . $product->sc_price . "' name='items[{$product->id}]' type='number' size='2' value='" . (int) $item->qty . "'/></td>";
			} else {
				$out .= "<td class='sc_number'>" . (int) $item->qty . "</td>";
			}

			$out .= "<td class='sc_number'>" . $this->renderPrice($total_price) . "</td>";
			if (!$viewOnly) $out .= "<td><a class='remove' href='./?sc_remove=" . $product->id . "'>" . $this->_("Remove") . "</a></td>";
			$out .= "</tr>";
		}

		if ($shippingModule) {
			$shippingCost = $shippingModule->calculateShippingCost();
			$shippingCost = $this->renderPrice($shippingCost);
			$out .= "<tr class='shippingRow'><td colspan='2'>". $this->_("Shipping costs") ."</td><td class='sc_number'>$shippingCost</td>";
			if (!$viewOnly) $out .= "<td>&nbsp;</td>";
			$out .= "</tr>";
		}

		$out .= "<tr class='final'><td colspan='2'>" . $this->_("Total:") . "</td><td id='total_sum'  class='sc_number'>". $this->renderPrice($total_sum) ."</td>";
		if (!$viewOnly) $out .= "<td>&nbsp;</td>";
		$out .= "</tr>";

		$out .= "</table>";

		if (!$viewOnly) {
			$out .= "<input type='submit' class='sc_update submit' name='sc_update' value=' " . $this->_("Update Cart") . "' />";
			if ($this->modules->isInstalled('ShoppingCheckout')) $out .= "<input type='submit' class='sc_checkout submit' name='sc_checkout' value=' " . $this->_("Continue to checkout") . "' />";
		}
		if (!$viewOnly) $out .= "</form>";

		return $out;
	}

	/**
	 * Returns true
	 *
	 * Removes product from cart
	 *
	 * @param Page $product Actual product that you want to remove
	 * @return true
	 *
	 */
	public function removeProductFromCart($product)
	{
		$this->addProductToCart($product, 0);
		return true;
	}

	public function renderPrice($price) {
		settype($price, "float");
		$price = number_format($price, $this->decimals, $this->dec_point, $this->thousands_sep);
		$space = ($this->spaceOnCurrency) ? " " : "";
		if ($this->currencyBefore == 1)
			return $this->currency . $space . $price;
		else
			return $price . $space . $this->currency;
	}

	public function checkStockAndReturnMaxQty($product, $qty) {

		if (!$this->checkStock($product, $qty)) {
			// If stock level fails, we add all there is and add notification about it
			$oldItems = $this->getCurrentCart();
			$qty = 0;
			foreach($oldItems as $p) {		// TODO: Probably better ways to do this than loop all?
				if ($product->id == $p->product_id && $product->sc_qty > 0) {
					$qty = $product->sc_qty;
				}
			}

			// Little bit different error message if it is totally over or just partly
			if ($qty > 0) $errormsg = sprintf(__("Sorry, but we don't have that many %s in stock. Added all we have in your cart."), $product->title);
			else $errormsg = sprintf(__("Sorry, but we don't have any %s in stock."), $product->title);

			$this->session->error($errormsg);

		}
		return $qty;
	}

	/**
	 * Returns cart items as JSON
	 *
	 * Updates the current cart
	 *
	 * @param array $products Simple array that has product_id:s as keys and qty as value array(123 => 4, 124 => 2)
	 * @return string with current items as JSON string
	 *
	 */
	public function updateCart(array $products)
	{
		$items = array();

		foreach ($products as $product_id => $qty) {
			// First we check if stock level for that product is good enough
			$product = $this->pages->get($product_id);
			$qty = $this->checkStockAndReturnMaxQty($product, $qty);

			if ($qty > 0)
				$items[] = $this->_newItem((int) $product_id, (int) $qty);
		}

		$total_sum = $this->getTotalSumFromItems($items);
		$items     = json_encode($items);

		$update = $this->db->query("UPDATE {$this->className} SET items = '$items', total_sum = $total_sum WHERE session_id = '" . $this->getSession() . "'");

		return $items;

	}

	public function getTotalSumFromItems($items, ShippingAbstract $shippingOption = NULL)
	{
		$total_sum = 0;
		if (count($items) < 1)
			return $total_sum;

		foreach ($items as $item) {
			$total_price = $this->getProductPriceTotal($item);
			$total_sum   = $total_sum + $total_price;
		}

		if ($shippingOption) {
			$total_sum = $total_sum + $shippingOption->calculateShippingCost();
		}

		return $total_sum;
	}

	public function ___getProductPriceTotal($item)
	{
		$price = $this->getProductPrice($item);
		$total_price = $item->qty * $price;
		return $total_price;
	}

	public function ___getProductPrice($item)
	{

		$product = $this->pages->get($item->product_id);

		// If the product is repeater, we assume it is a product variation. Se let's prepend the product title before variation
		if (strpos($product->template->name, "repeater_") === 0) {

			$parentProduct = $product->getForPage();
			if ($parentProduct->id) {
				// get product price from repeater page or if not set we get it from parent product
				if($product->sc_price && $product->sc_price > 0){
					$price = $product->sc_price;
				} else if($parentProduct->sc_price && $parentProduct->sc_price > 0) {
					$price = $parentProduct->sc_price;
				}
			}
			$price;
		} else {
			// get product price from actual product page
			$price = $product->sc_price;
		}

		return $price;

	}


	public function getCurrentCart()
	{
		$sid    = $this->getSession();
		$result = $this->db->query("SELECT items FROM {$this->className} WHERE session_id = '$sid' ORDER BY last_modified LIMIT 1");
		if ($result->num_rows === 0) {
			return array();
		} else {
			list($items) = $result->fetch_array();
			return json_decode($items);
		}
	}

	public function getTotalSumFromCart()
	{
		$items = $this->getCurrentCart();
		return $this->getTotalSumFromItems($items);
	}

	public function getNumberOfItems($uniqueItems = true)
	{
		if ($uniqueItems) {
			return count($this->getCurrentCart());
		} else {
			$qty = 0;
			foreach($this->getCurrentCart() as $item) {
				$qty += $item->qty;
			}
			return $qty;
		}
	}

	public function getSession() {
		if(isset($_COOKIE['pwshopSession']))
			return sha1($_COOKIE['pwshopSession']);

		setcookie("pwshopSession", session_id(), time()+60*60*24*7, "/"); // 7 days cookie
		return sha1(session_id());
	}

	private function _newItem($product_id, $qty)
	{
		$new_item             = new stdClass;
		$new_item->product_id = $product_id;
		$new_item->qty        = $qty;

		return $new_item;
	}

	static public function getModuleConfigInputfields(Array $data) {
		// this is a container for fields, basically like a fieldset
		$fields = new InputfieldWrapper();

		// since this is a static function, we can't use $this->modules, so get them from the global wire() function
		$modules = wire('modules');

		$data = array_merge(self::getDefaultData(), $data);

		$fields = new InputfieldWrapper();

		// since this is a static function, we can't use $this->modules, so get them from the global wire() function
		$modules = wire('modules');


		$f = $modules->get("InputfieldText");
		$f->attr('name', 'currencyCode');
		$f->attr('value', $data['currencyCode']);
		$f->label = "Currency Code";
		$f->description = "Put official ISO currency code here: http://en.wikipedia.org/wiki/Currency_codes";
		$fields->add($f);

		$f = $modules->get("InputfieldText");
		$f->attr('name', 'currency');
		$f->attr('value', $data['currency']);
		$f->label = "Currency output";
		$f->description = "How currency will be outputted in html markup? Ie. &amp;euro;";
		$fields->add($f);

		$f = $modules->get("InputfieldText");
		$f->attr('name', 'dec_point');
		$f->attr('value', $data['dec_point']);
		$f->label = "Decimal point on prices";
		$fields->add($f);

		$f = $modules->get("InputfieldText");
		$f->attr('name', 'thousands_sep');
		$f->attr('value', $data['thousands_sep']);
		$f->label = "Thousands separator on prices";
		$fields->add($f);

		$f = $modules->get("InputfieldInteger");
		$f->attr('name', 'decimals');
		$f->attr('value', $data['decimals']);
		$f->label = "Number of decimals on prices";
		$fields->add($f);

		$f = $modules->get("InputfieldCheckbox");
		$f->name = 'currencyBefore';
		$f->label = "Show currency before price?";
		$f->value = 1;
		$f->attr('checked', empty($data['currencyBefore']) ? '' : 'checked');
		$fields->add($f);

		$f = $modules->get("InputfieldCheckbox");
		$f->name = 'spaceOnCurrency';
		$f->label = "Show space between price and currency?";
		$f->value = 1;
		$f->attr('checked', empty($data['spaceOnCurrency']) ? '' : 'checked');
		$fields->add($f);

		$f = $modules->get("InputfieldCheckbox");
		$f->name = 'allowNegativeStock';
		$f->label = "Allow negative stock?";
		$f->description = "If you choose this, customers are able to buy products that you don't have enough in stock";
		$f->value = 1;
		$f->attr('checked', empty($data['allowNegativeStock']) ? '' : 'checked');
		$fields->add($f);


		return $fields;
	}

	public function install()
	{
		if (!$this->fields->get('sc_price')) {
			$f            = new Field();
			$f->type      = $this->modules->get("FieldtypeFloat");
			$f->name      = 'sc_price';
			$f->precision = 2;
			$f->label     = 'Price of the product';
			$f->save();
		}

		if (!$this->fields->get('sc_qty')) {
			$f = new Field();
			$f->type = $this->modules->get("FieldtypeInteger");
			$f->name = 'sc_qty';
			$f->label = 'Quantity';
			$f->save();
		}

		$sql = <<< _END

		CREATE TABLE {$this->className} (
			session_id VARCHAR(255) NULL,
			last_modified TIMESTAMP NOT NULL default CURRENT_TIMESTAMP on update CURRENT_TIMESTAMP,
			items TEXT NULL,
			total_sum FLOAT(10,2) NULL,
			user_id INT NULL,
			PRIMARY KEY (`session_id`) )
		  ENGINE = MyISAM DEFAULT CHARSET=utf8;

_END;

		$this->db->query($sql);
	}

	public function uninstall()
	{
		$this->db->query("DROP TABLE {$this->className}");
	}
}