<?php
    // since want to use $_SESSION array here, need:

    session_start();
?>

<!DOCTYPE html>
<html lang="en" xmlns="http://www.w3.org/1999/xhtml">

<!--
    using session variables to control a multi-state
    application

    by: Sharon Tuttle
    last modified: 2026-04-21

    you can run this using the URL:
https://nrs-projects.humboldt.edu/~st10/s26cs328/328lect13-1/try-quad.php
-->

<head>
    <title> try-quad </title>
    <meta charset="utf-8" />

    <?php
        // turn on error reporting
	
        ini_set('display_errors', 1);
        error_reporting(E_ALL);

        // bring in some needed PHP functions

        require_once("request_name.php");
        require_once("request_quest.php");
        require_once("request_color.php");
        require_once("show_farewell.php");
        require_once("complain_and_exit.php");
        require_once("build_mini_form.php");
    ?>

    <link href="https://nrs-projects.humboldt.edu/~st10/styles/normalize.css"
          type="text/css" rel="stylesheet" />
</head>

<body>
    <h1> try-quad </h1>

    <?php
    // I decide to make and use a $_SESSION key next_state
    //   to help navigate through the states in my application

    // if next_state is NOT a key in $_SESSION, start at the
    //     first state, request_name

    if (! array_key_exists("next_state", $_SESSION))
    {
        request_name();
	$_SESSION["next_state"] = "quest";
    }

    // otherwise, use $_SESSION["next_state"]'s value to
    //     to determine the next state to give the user

    elseif ($_SESSION["next_state"] == "quest")
    {
        request_quest();
	$_SESSION["next_state"] = "color";
    }
    elseif ($_SESSION["next_state"] == "color")
    {
        request_color();
	$_SESSION["next_state"] = "farewell";
    }
    elseif ($_SESSION["next_state"] == "farewell")
    {
        show_farewell();
	session_destroy();
    }

    // I HOPE I cannot reach this, but JUST in case...

    else
    {
        session_destroy();
	?>
	<p> <strong> YIKES! should NOT have been able to reach here!
	    </strong> </p>
        <p> <a href="<?= htmlentities($_SERVER["PHP_SELF"],
                                           ENT_QUOTES) ?>">
            Start over </a> </p>
	<?php
    }
    ?>

    <footer>
    <hr />
    <p>
        Validate by pasting .xhtml copy's URL into<br />
	<a href="https://validator.w3.org/nu">
            https://validator.w3.org/nu
        </a>
	or  
        <a href="https://html5.validator.nu/">
            https://html5.validator.nu/
        </a>
    </p>
    </footer>
</body>
</html>