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<?php
// MODEL/database.php
    $dsn = 'mysql:host=localhost;dbname=my_guitar_shop1';
    $username = 'mgs_user';
    $password = 'pa55word';

    try {
        $db = new PDO($dsn, $username, $password);
    } catch (PDOException $e) {
        $error_message = $e->getMessage();
        include('../errors/database_error.php');
        exit();
    }
    
    
// MODEL/category_db.php

function get_categories() {
    global $db;
    $query = 'SELECT * FROM categories
              ORDER BY categoryID';
    $statement = $db->prepare($query);
    $statement->execute();
    return $statement;    
}

function get_category_name($category_id) {
    global $db;
    $query = 'SELECT * FROM categories
              WHERE categoryID = :category_id';    
    $statement = $db->prepare($query);
    $statement->bindValue(':category_id', $category_id);
    $statement->execute();    
    $category = $statement->fetch();
    $statement->closeCursor();    
    $category_name = $category['categoryName'];
    return $category_name;
}


// #############################################################################

// MODEL/product_db.php

function get_products_by_category($category_id) {
    global $db;
    $query = 'SELECT * FROM products
              WHERE products.categoryID = :category_id
              ORDER BY productID';
    $statement = $db->prepare($query);
    $statement->bindValue(":category_id", $category_id);
    $statement->execute();
    $products = $statement->fetchAll();
    $statement->closeCursor();
    return $products;
}

function get_product($product_id) {
    global $db;
    $query = 'SELECT * FROM products
              WHERE productID = :product_id';
    $statement = $db->prepare($query);
    $statement->bindValue(":product_id", $product_id);
    $statement->execute();
    $product = $statement->fetch();
    $statement->closeCursor();
    return $product;
}

function delete_product($product_id) {
    global $db;
    $query = 'DELETE FROM products
              WHERE productID = :product_id';
    $statement = $db->prepare($query);
    $statement->bindValue(':product_id', $product_id);
    $statement->execute();
    $statement->closeCursor();
}

function add_product($category_id, $code, $name, $price) {
    global $db;
    $query = 'INSERT INTO products
                 (categoryID, productCode, productName, listPrice)
              VALUES
                 (:category_id, :code, :name, :price)';
    $statement = $db->prepare($query);
    $statement->bindValue(':category_id', $category_id);
    $statement->bindValue(':code', $code);
    $statement->bindValue(':name', $name);
    $statement->bindValue(':price', $price);
    $statement->execute();
    $statement->closeCursor();
}



// #############################################################################

// VIEW/product_add.php

<?php include '../view/header.php'; ?>
<main>
    <h1>Add Product</h1>
    <form action="index.php" method="post" id="add_product_form">
        <input type="hidden" name="action" value="add_product">

        <label>Category:</label>
        <select name="category_id">
        <?php foreach ( $categories as $category ) : ?>
            <option value="<?php echo $category['categoryID']; ?>">
                <?php echo $category['categoryName']; ?>
            </option>
        <?php endforeach; ?>
        </select>
        <br>

        <label>Code:</label>
        <input type="text" name="code" />
        <br>

        <label>Name:</label>
        <input type="text" name="name" />
        <br>

        <label>List Price:</label>
        <input type="text" name="price" />
        <br>

        <label>&nbsp;</label>
        <input type="submit" value="Add Product" />
        <br>
    </form>
    <p class="last_paragraph">
        <a href="index.php?action=list_products">View Product List</a>
    </p>

</main>
<?php include '../view/footer.php'; ?>



<?php
// VIEW/product_list.php

<?php include '../view/header.php'; ?>
<main>
    <h1>Product List</h1>

    <aside>
        <!-- display a list of categories -->
        <h2>Categories</h2>
        <nav>
        <ul>
        <?php foreach ($categories as $category) : ?>
            <li>
            <a href="?category_id=<?php echo $category['categoryID']; ?>">
                <?php echo $category['categoryName']; ?>
            </a>
            </li>
        <?php endforeach; ?>
        </ul>
        </nav>
    </aside>

    <section>
        <!-- display a table of products -->
        <h2><?php echo $category_name; ?></h2>
        <table>
            <tr>
                <th>Code</th>
                <th>Name</th>
                <th class="right">Price</th>
                <th>&nbsp;</th>
            </tr>
            <?php foreach ($products as $product) : ?>
            <tr>
                <td><?php echo $product['productCode']; ?></td>
                <td><?php echo $product['productName']; ?></td>
                <td class="right"><?php echo $product['listPrice']; ?></td>
                <td><form action="." method="post">
                    <input type="hidden" name="action"
                           value="delete_product">
                    <input type="hidden" name="product_id"
                           value="<?php echo $product['productID']; ?>">
                    <input type="hidden" name="category_id"
                           value="<?php echo $product['categoryID']; ?>">
                    <input type="submit" value="Delete">
                </form></td>
            </tr>
            <?php endforeach; ?>
        </table>
        <p class="last_paragraph">
            <a href="?action=show_add_form">Add Product</a>
        </p>
    </section>
</main>
<?php include '../view/footer.php'; ?>



<?php
// #############################################################################


// CONTROLLER/index.php

require('../model/database.php');
require('../model/product_db.php');
require('../model/category_db.php');

$action = filter_input(INPUT_POST, 'action');
if ($action == NULL) {
    $action = filter_input(INPUT_GET, 'action');
    if ($action == NULL) {
        $action = 'list_products';
    }
}

if ($action == 'list_products') {
    $category_id = filter_input(INPUT_GET, 'category_id', 
            FILTER_VALIDATE_INT);
    if ($category_id == NULL || $category_id == FALSE) {
        $category_id = 1;
    }
    $category_name = get_category_name($category_id);
    $categories = get_categories();
    $products = get_products_by_category($category_id);
    include('product_list.php');
} else if ($action == 'delete_product') {
    $product_id = filter_input(INPUT_POST, 'product_id', 
            FILTER_VALIDATE_INT);
    $category_id = filter_input(INPUT_POST, 'category_id', 
            FILTER_VALIDATE_INT);
    if ($category_id == NULL || $category_id == FALSE ||
            $product_id == NULL || $product_id == FALSE) {
        $error = "Missing or incorrect product id or category id.";
        include('../errors/error.php');
    } else { 
        delete_product($product_id);
        header("Location: .?category_id=$category_id");
    }
} else if ($action == 'show_add_form') {
    $categories = get_categories();
    include('product_add.php');    
} else if ($action == 'add_product') {
    $category_id = filter_input(INPUT_POST, 'category_id', 
            FILTER_VALIDATE_INT);
    $code = filter_input(INPUT_POST, 'code');
    $name = filter_input(INPUT_POST, 'name');
    $price = filter_input(INPUT_POST, 'price', FILTER_VALIDATE_FLOAT);
    if ($category_id == NULL || $category_id == FALSE || $code == NULL || 
            $name == NULL || $price == NULL || $price == FALSE) {
        $error = "Invalid product data. Check all fields and try again.";
        include('../errors/error.php');
    } else { 
        add_product($category_id, $code, $name, $price);
        header("Location: .?category_id=$category_id");
    }
}