functions.php

<?php

function set_message($message) {
	if (!empty($message)) {
		$_SESSION['message'] = $message;
	} else {
		$message = "";
	}
}

function display_message() {

	if (isset($_SESSION['message'])) {
		echo $_SESSION['message'];
		unset($_SESSION['message']);
	}

}

function redirect($location) {
	return header("Location: $location");
}

function query($sql) {
	global $connection;
	return mysqli_query($connection, $sql);
}

function confirm($result) {
	global $connection;

	if (!$result) {
		die("QUERY FAILED " . mysqli_error($connection));
	}
}

function escape_string($string) {
	global $connection;
	return mysqli_real_escape_string($connection, $string);
}

function fetch_array($result) {
	return mysqli_fetch_array($result);
}

function get_four_products() {
	$query = query("SELECT * FROM products");
	$count = 0;
	confirm($query);

	while ($row = fetch_array($query)) {

		if ($count < 8) {
			$product = <<<DELIMETER
		    <div class="col-4">
		    	<a href="product_detail.php?id={$row['product_id']}"><img src="uploads/{$row['product_image']}"></a>
		    	<h4><a href="product_detail.php?id={$row['product_id']}">{$row['product_title']}</a></h4>
		    	<p style="color: red;">&#36;{$row['product_price']}</p>
		    	<p>{$row['product_short_desc']}</p>
		        <a class="btn" href="cart.php?add={$row['product_id']}">Add to cart</a>
		    </div>
		DELIMETER;

		echo $product;
		$count = $count + 1;
		}
		
	}
}

function get_products() {
	$query = query("SELECT * FROM products");
	confirm($query);

	while ($row = fetch_array($query)) {
		
		$product = <<<DELIMETER
		    <div class="col-4">
		    	<a href="product_detail.php?id={$row['product_id']}"><img width='100' src="uploads/{$row['product_image']}"></a>
		    	<h4><a href="product_detail.php?id={$row['product_id']}">{$row['product_title']}</a></h4>
		    	<p style="color: red;">&#36;{$row['product_price']}</p>
		    	<p>{$row['product_short_desc']}</p>
		        <a class="btn" href="cart.php?add={$row['product_id']}">Add to cart</a>
		    </div>
		DELIMETER;

		echo $product;

	}
}


function login_user() {

	if(isset($_POST['submit'])) {
		$username = escape_string($_POST['username']);
		$password = escape_string($_POST['password']);

		$query = query("SELECT * FROM users WHERE username = '{$username}' AND password = '{$password}'");
		confirm($query);

		if (mysqli_num_rows($query) == 0) {
			set_message("Incorrect username or password. Please try again.");
			redirect("login_page.php");
		} else {
			while ($row = fetch_array($query)) {

		      $user_id = escape_string($row['user_id']);
		    }
		    $_SESSION['user_id'] = $user_id;
			$_SESSION['username'] = $username;

			if ($username == 'admin' && $password == '1234') {
				redirect("admin_index.php");
			} else {
				redirect("homepage.php");
			}
		}
	}
}


function add_user() {

	if(isset($_POST['add_user'])) {

		$username = escape_string($_POST['username']);
		$email = escape_string($_POST['email']);
		$password = escape_string($_POST['password']);

		$query = query("INSERT INTO users(username,email,password) VALUES('{$username}','{$email}','{$password}')");
		confirm($query);

		set_message("USER CREATED");

		redirect("homepage.php");

	}
}


function add_product_user() {

	if(isset($_POST['publish'])) {


		$product_title = escape_string($_POST['product_title']);
		$product_category_id = escape_string($_POST['product_category_id']);
		$product_price = escape_string($_POST['product_price']);
		$product_description = escape_string($_POST['product_description']);
		$product_short_desc = escape_string($_POST['product_short_desc']);
		$product_quantity = escape_string($_POST['product_quantity']);
		$product_image = escape_string($_FILES['file']['name']);
		$image_temp_location = escape_string($_FILES['file']['tmp_name']);

		move_uploaded_file($image_temp_location  , UPLOAD_DIRECTORY . DS . $product_image);


		$query = query("INSERT INTO products(product_title, product_category_id, product_price, product_description, product_short_desc, product_quantity, product_image) VALUES('{$product_title}', {$product_category_id}, {$product_price}, '{$product_description}', '{$product_short_desc}', {$product_quantity}, '{$product_image}')");
		confirm($query);
		redirect("update_product_page.php");


	} 

	if(isset($_POST['back'])) {
		redirect("products.php");
	}

}

function show_product_category_title($product_category_id) {

	$category_query = query("SELECT * FROM categories WHERE cat_id = {$product_category_id} ");
	confirm($category_query);

	while ($category_row = fetch_array($category_query)) {
		return $category_row['cat_title'];
	}

}



function get_products_update_page() {

	$query = query("SELECT * FROM products");
	confirm($query);

	while ($row = fetch_array($query)) {

		$category = show_product_category_title($row['product_category_id']);
		
		$product = <<<DELIMETER
		<tr>
		    <td>{$row['product_id']}</td>
		    <td><a href="product_detail.php?id={$row['product_id']}"><img src="uploads/{$row['product_image']}" width=100></td></a>
		    <td><a href="update_product.php?id={$row['product_id']}">{$row['product_title']}</a><br>
		    </td>
		    <td>{$category}</td>
		    <td>&#36;{$row['product_price']}</td>
		    <td>{$row['product_quantity']}</td>
		    <td><a class="btn" href="delete_product.php?id={$row['product_id']}">Remove</a></td>
		</tr>
		DELIMETER;

		echo $product;

	}
}

function get_category_products() {
	$query = query("SELECT * FROM products WHERE product_category_id = " . escape_string($_GET['id']) . " ");
	confirm($query);

	while ($row = fetch_array($query)) {
		
	$product = <<<DELIMETER
	<div class="col-4">
		    	<a href="product_detail.php?id={$row['product_id']}"><img width='100' src="uploads/{$row['product_image']}"></a>
		    	<h4><a href="product_detail.php?id={$row['product_id']}">{$row['product_title']}</a></h4>
		    	<p style="color: red;">&#36;{$row['product_price']}</p>
		    	<p>{$row['product_short_desc']}</p>
		        <a class="btn btn-primary" target="_blank" href="cart.php?add={$row['product_id']}">Add to cart</a>
		    </div>
	DELIMETER;

		echo $product;

	}
}

function update_product() {

	if(isset($_POST['update'])) {


		$product_title          = escape_string($_POST['product_title']);
		$product_category_id    = escape_string($_POST['product_category_id']);
		$product_price          = escape_string($_POST['product_price']);
		$product_description    = escape_string($_POST['product_description']);
		$product_short_desc     = escape_string($_POST['product_short_desc']);
		$product_quantity       = escape_string($_POST['product_quantity']);
		$product_image          = escape_string($_FILES['file']['name']);
		$image_temp_location    = escape_string($_FILES['file']['tmp_name']);

		if(empty($product_image)) {

			$get_pic = query("SELECT product_image FROM products WHERE product_id =" .escape_string($_GET['id']). " ");
			confirm($get_pic);

			while($pic = fetch_array($get_pic)) {

				$product_image = $pic['product_image'];

		    }

		}


		move_uploaded_file($image_temp_location  , UPLOAD_DIRECTORY . DS . $product_image);

		$query = "UPDATE products SET ";
		$query .= "product_title = '{$product_title}', ";
		$query .= "product_category_id = '{$product_category_id}', ";
		$query .= "product_price = '{$product_price}', ";
		$query .= "product_description = '{$product_description}', ";
		$query .= "product_short_desc = '{$product_short_desc}', ";
		$query .= "product_quantity = '{$product_quantity}', ";
		$query .= "product_image = '{$product_image}'";
		$query .= "WHERE product_id=" . escape_string($_GET['id']);

		$send_update_query = query($query);
		confirm($send_update_query);
		set_message("Product has been updated");
		redirect("update_product_page.php");


	} 

	if(isset($_POST['back'])) {
		redirect("update_product_page.php");
	}
}

function update_user() {

	if(isset($_POST['update_user'])) {

		$username = escape_string($_POST['username']);
      	$email = escape_string($_POST['email']);
      	$password = escape_string($_POST['password']);

      	$_SESSION['username'] = $username;
	
		$query = "UPDATE users SET ";
		$query .= "username = '{$username}', ";
		$query .= "email = '{$email}', ";
		$query .= "password = '{$password}' ";
		$query .= "WHERE user_id=" . escape_string($_GET['id']);

		$send_update_query = query($query);
		confirm($send_update_query);
		set_message("User has been updated");
		redirect("homepage.php");
	} 
}


function get_categories() {

	$query = query("SELECT * FROM categories");
	confirm($query);

	while ($row = fetch_array($query)) {

		$category_links = <<<DELIMETER
		  
		  <a href="category_page.php?id={$row['cat_id']}">{$row['cat_title']}</a>

		DELIMETER;

		echo $category_links;
	}
}


function show_categories_add_product() {

	$query = query("SELECT * FROM categories");
	confirm($query);

	while ($row = fetch_array($query)) {

		$category_options = <<<DELIMETER
		<option value="{$row['cat_id']}">{$row['cat_title']}</option>
		DELIMETER;

		echo $category_options;

	}
}

function search() {
	if(isset($_POST['search_product'])) {
		$search = escape_string($_POST['search']);
		$_SESSION['product_name'] = $search;
		redirect("search.php?search=$search");

	}
}


function show_categories_in_admin() {

	$category_query = query("SELECT * FROM categories");
	confirm($category_query);

	while($row = fetch_array($category_query)) {

		$cat_id = $row['cat_id'];
		$cat_title = $row['cat_title'];

		$category = <<<DELIMETER
		<tr>
		    <td>{$cat_id}</td>
		    <td style="padding-left: 60px;">{$cat_title}</td>
		    <td style="padding-left: 60px;"><a style="color:red;" href="delete_category.php?id={$row['cat_id']}">Delete</a></td>
		</tr>
		DELIMETER;

		echo $category;

	}
}


function add_category() {

	if(isset($_POST['add_category'])) {
		$cat_title = escape_string($_POST['cat_title']);

		if(empty($cat_title) || $cat_title == " ") {

			echo "<p class='bg-danger'>THIS CANNOT BE EMPTY</p>";

		} else {

		$insert_cat = query("INSERT INTO categories(cat_title) VALUES('{$cat_title}') ");
		confirm($insert_cat);
		set_message("Category Created");
		redirect("categories.php");

		}

	}

}



function get_products_admin_page() {

	$query = query("SELECT * FROM products");
	confirm($query);

	while ($row = fetch_array($query)) {

		$category = show_product_category_title($row['product_category_id']);
		
		$product = <<<DELIMETER
		<tr>
		    <td>{$row['product_id']}</td>
		    <td><img src="uploads/{$row['product_image']}" width=100></td>
		    <td><a href="admin_update_product.php?id={$row['product_id']}">{$row['product_title']}</a><br>
		    </td>
		    <td>{$category}</td>
		    <td>&#36;{$row['product_price']}</td>
		    <td>{$row['product_quantity']}</td>
		    <td><a class="btn" href="admin_delete_product.php?id={$row['product_id']}">Remove</a></td>
		</tr>
		DELIMETER;

		echo $product;

	}


}


function add_product_admin() {

	if(isset($_POST['publish'])) {


		$product_title = escape_string($_POST['product_title']);
		$product_category_id = escape_string($_POST['product_category_id']);
		$product_price = escape_string($_POST['product_price']);
		$product_description = escape_string($_POST['product_description']);
		$product_short_desc = escape_string($_POST['product_short_desc']);
		$product_quantity = escape_string($_POST['product_quantity']);
		$product_image = escape_string($_FILES['file']['name']);
		$image_temp_location = escape_string($_FILES['file']['tmp_name']);

		move_uploaded_file($image_temp_location  , UPLOAD_DIRECTORY . DS . $product_image);


		$query = query("INSERT INTO products(product_title, product_category_id, product_price, product_description, product_short_desc, product_quantity, product_image) VALUES('{$product_title}', {$product_category_id}, {$product_price}, '{$product_description}', '{$product_short_desc}', {$product_quantity}, '{$product_image}')");
		confirm($query);
		redirect("admin_products.php");


	} 

	if(isset($_POST['back'])) {
		redirect("admin_index.php");
	}

}



function update_product_admin() {

	if(isset($_POST['publish'])) {


		$product_title          = escape_string($_POST['product_title']);
		$product_category_id    = escape_string($_POST['product_category_id']);
		$product_price          = escape_string($_POST['product_price']);
		$product_description    = escape_string($_POST['product_description']);
		$product_short_desc     = escape_string($_POST['product_short_desc']);
		$product_quantity       = escape_string($_POST['product_quantity']);
		$product_image          = escape_string($_FILES['file']['name']);
		$image_temp_location    = escape_string($_FILES['file']['tmp_name']);

		if(empty($product_image)) {

			$get_pic = query("SELECT product_image FROM products WHERE product_id =" .escape_string($_GET['id']). " ");
			confirm($get_pic);

			while($pic = fetch_array($get_pic)) {

				$product_image = $pic['product_image'];

		    }

		}


		move_uploaded_file($image_temp_location  , UPLOAD_DIRECTORY . DS . $product_image);

		$query = "UPDATE products SET ";
		$query .= "product_title = '{$product_title}', ";
		$query .= "product_category_id = '{$product_category_id}', ";
		$query .= "product_price = '{$product_price}', ";
		$query .= "product_description = '{$product_description}', ";
		$query .= "product_short_desc = '{$product_short_desc}', ";
		$query .= "product_quantity = '{$product_quantity}', ";
		$query .= "product_image = '{$product_image}'";
		$query .= "WHERE product_id=" . escape_string($_GET['id']);

		$send_update_query = query($query);
		confirm($send_update_query);
		set_message("Product has been updated");
		redirect("admin_products.php");


	} 

	if(isset($_POST['back'])) {
		redirect("admin_index.php");
	}

}



function add_user_admin() {

	if(isset($_POST['add_user'])) {

		$username = escape_string($_POST['username']);
		$email = escape_string($_POST['email']);
		$password = escape_string($_POST['password']);

		$query = query("INSERT INTO users(username,email,password) VALUES('{$username}','{$email}','{$password}')");
		confirm($query);

		set_message("USER CREATED");

		redirect("users.php");


	}

}


function display_users() {

	$user_query = query("SELECT * FROM users");
	confirm($user_query);


	while($row = fetch_array($user_query)) {

		$user_id = $row['user_id'];
		$username = $row['username'];
		$email = $row['email'];
		$password = $row['password'];

		$user = <<<DELIMETER
		<tr>
		    <td>{$user_id}</td>
		    <td style="padding-left: 50px;">{$username}</td>
		    <td style="padding-left: 50px;">{$email}</td>
		    <td><a style="color:red; padding-left: 30px;" class="btn btn-danger" href="delete_user.php?id={$row['user_id']}">Delete User</a>
		</tr>
		DELIMETER;

		echo $user;

	}
}

?>