Untitled

<?php
    $dbServername = "localhost";
    $dbUsername = "root";
    $dbPassword = "";
    $dbName = "assignment2";

    $conn = mysqli_connect($dbServername, $dbUsername, $dbPassword, $dbName)
?>

<!DOCTYPE html>
<html>
<head>
    <link rel="stylesheet" href="https://stackpath.bootstrapcdn.com/bootstrap/4.1.3/css/bootstrap.min.css" integrity="sha384-MCw98/SFnGE8fJT3GXwEOngsV7Zt27NXFoaoApmYm81iuXoPkFOJwJ8ERdknLPMO" crossorigin="anonymous">
    <title>Assignment 2</title>
</head>

<body style="margin: 2%;">
    <form method="post">
        Choose a class:
        <select name="course">
            <option value="creative_cupcakes">Creative Cupcakes</option>
            <option value="digital_photography">Digital Photography</option>
            <option value="family_history">Family History for Beginners</option>
            <option value="acrylic_painting">Fundamentals of Acrylic Painting</option>
            <option value="holiday_french">Holiday French</option>
        </select>
        <br />
        <input type="submit" value="Select">
    </form>
    <br />

     <?php
        // If the user's picked a course, show the next form
        if (isset($_POST['course'])) {
            $title = $_POST["course"];
            $GLOBALS["course"] = $title;
            // Grab the selected course for the slots where capacity is above 0
            $sql = "SELECT * FROM courses WHERE title='$title' AND capacity > 0";
            $result = mysqli_query($conn, $sql);

            // Render the form for each slot
            echo "<form method='post'> Choose a timeslot for ".$title;
            echo "<br />";
            while($row = mysqli_fetch_assoc($result)) {
                echo "<input type='radio' name='slot' value='".$row['slot']."'>";
                echo $row['slot']." - ".$row['capacity']." spaces left";
                echo "</input> <br/>";
            }
            echo "<input type='hidden' name='course' value='".$title."'>";
            echo "<br/ > Name: <input type='text' name='name'> <br />";
            echo "Phone Number: <input type='text' name='number'> <br /> <br />";
            echo "<input type='submit' value='Submit'> </form>";
        }
    ?>

    <?php
        // If the user's picked a slot, run the confirmation
        if (isset($_POST['name']) && isset($_POST['number']) && isset($_POST['slot'])) {
            $course = $_POST['course'];
            $name = $_POST['name'];
            $number = $_POST['number'];
            $slot = $_POST['slot'];
            // Validate name
            if (ereg("[\sa-zA-z'-]", $name)) {
                // Validate number
                if (is_numeric($number)) {
                    // Insert new booking
                    $sql = "INSERT INTO bookings (course, name, number, slot) VALUES ('$course', '$name', $number, '$slot')";
                    mysqli_query($conn, $sql);

                    // Update existing capacity
                    $sql = "SELECT capacity FROM courses WHERE title='$title' && slot='$slot' LIMIT 1";
                    $result = mysqli_query($conn, $sql);
                    $row = mysqli_fetch_assoc($result);
                    $capacity = $row['capacity'] - 1;
                    $sql = "UPDATE courses SET capacity=$capacity WHERE title='$title' && slot='$slot'";
                    mysqli_query($conn, $sql);

                    echo "Booking successful!";
                } else {
                    echo "Invalid number";
                }
            } else {
                echo "Invalid name";
            }
        }
    ?>
</body>
</html>