CÓDIGO VIEW

<h1>Compras</h1>
<div class="button"><a href="<?php echo BASE_URL; ?>/purchases/add">Adicionar Compra</a></div>

<table width="100%" border="0">
	<tr>
		<th>Nome do Cliente</th>
		<th>Data</th>
		<th>Valor</th>
		<th>Ações</th>
	</tr>
	<?php foreach($purchases_list as $purchaseitme): ?>
		<tr>
			<td><?php echo $purchaseitme['name'] ?></td>
			<td><?php echo date('d/m/Y', strtotime($purchaseitme['date_purchase'])); ?></td>
			<td>R$ <?php echo number_format($purchaseitme['total_price'], 2, ',', '.'); ?></td>
			<td>
				<div class="button button_small"><a href="<?php echo BASE_URL; ?>/sales/edit/<?php echo $purchaseitme['id']; ?>">Editar</a></div>
			</td>
		</tr>
	<?php endforeach; ?>
</table>

CÓDIGO CONTROLLER

<?php
class purchasesController extends controller{

	public function __construct() {
        parent::__construct();

        $u = new Users();
        if($u->isLogged() == false){
        	header("Location: ".BASE_URL."/login");
        	exit;
        }
    }
    public function index(){

    	$data = array();
    	$u = new Users();
    	$u->setLoggedUser();
    	$company = new Companies($u->getCompany());

    	$data['company_name'] = $company->getName();
        $data['user_email'] = $u->getEmail();

        $data['statuses'] = array(
            '0' => 'Aguardando Pgto.',
            '1' => 'Pago',
            '2' => 'Cancelado'
        );

        if($u->hasPermission('purchases_view')){
            $p = new Purchases();
            $offset = 0;

            $data['purchases_list'] = $p->getList($offset, $u->getCompany());

            $this->loadTemplate("purchases", $data);
        }else{
            header("Location: ".BASE_URL);
        }
    }
      public function add(){
       $data = array();
        $u = new Users();
        $u->setLoggedUser();
        $company = new Companies($u->getCompany());

        $data['company_name'] = $company->getName();
        $data['user_email'] = $u->getEmail();

        if($u->hasPermission('purchases_view')){
            $p = new Purchases();

            if(isset($_POST['client_id']) && !empty($_POST['client_id'])){
                $client_id = addslashes($_POST['client_id']);
                $status = addslashes($_POST['status']);
                $quant = $_POST['quant'];

                $p->addPurchases($u->getCompany(), $client_id, $u->getId(), $quant, $status);
                header("Location: ".BASE_URL."/purchases");
            }

            $this->loadTemplate("purchases_add", $data);
        }else{
            header("Location: ".BASE_URL);
        }
    }
}

CÓDIGO MODEL

<?php
class Purchases extends Model{

	public function getList($offset, $id_company){
		$array = array();

		$sql = $this->db->prepare("
			SELECT
				purchases.id,
			    purchases.date_purchase,
			    purchases.total_price,
			    clients.name
		    FROM purchases
		    LEFT JOIN clients ON clients.id = purchases.id_user
		    WHERE purchases.id_company = :id_company
		    ORDER BY purchases.date_purchase DESC
		    LIMIT $offset, 10");
		$sql->bindValue(":id_company", $id_company);
		$sql->execute();

		if($sql->rowCount() > 0){
			$array = $sql->fetchAll();
		}
		return $array;
	}
	public function addPurchases($id_company,  $id_user, $quant, $total_price){
		$i = new Inventory();

		$sql = $this->db->prepare("INSERT INTO purchases (id_company, id_user, date_purchase, total_price) VALUES (:id_company, :id_user, NOW(), :total_price)");
		$sql->bindValue(":id_company", $id_company);
		$sql->bindValue(":id_user", $id_user);
		$sql->bindValue(":total_price", '0');
		$sql->execute();


		$id_sale = $this->db->lastInsertId();

		$total_price = 0;

		foreach($quant as $id_prod => $quant_prod){
			$sql = $this->db->prepare("SELECT price FROM inventory WHERE id = :id AND id_company = :id_company");
			$sql->bindValue(":id", $id_prod);
			$sql->bindValue(":id_company", $id_company);
			$sql->execute();

			if($sql->rowCount() > 0){
				$row = $sql->fetch();
				$price = $row['price'];

				$sqlp = $this->db->prepare("INSERT INTO purchases_products (id_company, id_purchase, name, quant, purchase_price) VALUES (:id_company, :id_purchase, :id_product, :quant, :purchase_price)");
				$sqlp->bindValue(":id_company", $id_company);
				$sqlp->bindValue(":id_purchases", $id_purchases);
				$sqlp->bindValue(":name", $name);
				$sqlp->bindValue(":id_product", $id_prod);
				$sqlp->bindValue(":quant", $quant_prod);
				$sqlp->bindValue(":purchase_price", $price);
				$sqlp->execute();

				$i->decrease($id_prod, $id_company, $quant_prod, $id_user);

				$total_price += $price * $quant_prod;
			}
		}

		$sql = $this->db->prepare("UPDATE purchases SET total_price = :total_price WHERE id = :id");
		$sql->bindValue(":total_price", $total_price);
		$sql->bindValue(":id", $id_sale);
		$sql->execute();
	}
}