<?php
    /*-----
        function: show_farewell
        purpose: expects nothing, returns nothing,
            but has the side-effects of trying to
            read the desired color from the requesting
            form, and uses it along with prior
            session name and quest to create a form
            bidding the user farewell
    -----*/
    
    function show_farewell()
    {
        // if get here -- better be a color in $_POST!

        // (trim removes leading and trailing blanks
        //     from a string... 8-) )

        if ( (! array_key_exists('color', $_POST)) or
           (! isset($_POST['color']) ) or
           (trim($_POST['color']) == "") )
        {
            complain_and_exit("color");
        }

        // if get here -- I think I can proceed

        $fave_color = strip_tags($_POST['color']);

        $user_name = strip_tags($_SESSION['name']);
        $user_quest = strip_tags($_SESSION['quest']);

        ?>

        <h2> 
            AHA, <?= $user_name ?>, 
            lover of the gentle hue of <?= $fave_color ?>,
            I let you pass, and wish you WELL on your
            quest for:
            <?= $user_quest ?> 
        </h2>

        <form method="post"
              action="<?= htmlentities($_SERVER['PHP_SELF'],
                                       ENT_QUOTES) ?>">
            <input type="submit" value="return to beginning" />
        </form>
        <?php
    }
?>