问为网站制定订阅计划

EN

plans table:
id    name      cost
1     Basic      0.00    
2     Silver    20.00
3     Gold      30.00
4     Platinum  50.00

plans_period table:
id    sub_period
1     1
2     3
3     6
4     12

users table:
user_id  plan  plan_cost      user_plan_period  balance         plan_expiration
1        2     0.00(default)  0 (default)       0.00 (default)  NULL (default)

if ($plan & $period) {
    $user = new fncs();
    // What plan was chosen?
    list($name, $cost) = $db->get_row("select name, cost from plans where id='$plan'", ARRAY_N);
    list($sub_period) = $db->get_row("select sub_period from plans_period where sub_period='$period'", ARRAY_N);
    list($plan, $user_plan_period, $plan_cost, $plan_expiration) = $db->get_row("select u.plan, u.user_plan_period, u.plan_cost, u.plan_expiration, p.id from users u LEFT JOIN plans p ON p.id=u.plan where u.user_id='{$_SESSION['user_id']}'", ARRAY_N);
    $plan_expiration = ($plan_expiration = "NULL") ? '30' : '$plan_expiration';
    /*Current Cost of plan chosen */
    $totalcost1 = $cost * $sub_period;
    /* Cost of the user current plan */
    $totalcost2 = $plan_cost * $user_plan_period;
    /* Total number of days of the user current plan */
    $totaldays1 = 30 * $user_plan_period;
    /* Total number of days of the left for the user current plan */
    $today = date("m-d-Y"); 
    $dateDiff = strtotime($plan_expiration) - strtotime($today);
    $Daysleft = floor($dateDiff/(60*60*24));

    $totaldays2 = $totaldays1 - $Daysleft;

    $expiredate = strtotime($plan_expiration);

    $totalcost =  $totalcost1 -  ($totalcost2 * ($Daysleft / $totaldays1));

    $finalcost = number_format($totalcost, 2);

    // sufficient balance?
    if ($totalcost > $user->getBalance())
    {
        $errs[] = 'You have insufficient balance for the upgrade. The total cost is: '.$Daysleft.'';
    }
    else {
        $r = $db->query("update users set plan='$plan', user_plan_period='$period', plan_cost='$cost', plan_expiration=date_add(now(), interval 30 day) where user_id='{$_SESSION['user_id']}'");
        // Update balance
        $balance = $user->getBalance() - $cost;
        $db->query("update users set balance='$balance' where user_id='{$_SESSION['user_id']}'");
        // Reset sessions
        $user->processLogin($_SESSION['email']);
        // Insert into transactions
        $txt = "Account upgrade: <strong>$name</strong> for <s>N</s>$cost. Expires ".$_SESSION['plan_expiration'];
        $db->query("insert into transactions (user_id, txt, direction, amount, balance, date) values ('{$_SESSION['user_id']}', '$txt', 'd', '$cost', '$balance', now())");
        $_SESSION['msg'] = 'Account successfully upgraded. Plan expires on '.$_SESSION['plan_expiration'];

        header('location:my-account.php');
        exit;
    }
}

<div class="mainbar">
    <h3>Upgrade Account</h3>
    <?php
    if (isset($errs)) {
        echo '<p class="alert">';
        foreach($errs as $v){
            echo "$v ";
        }
        echo '</p>';
    }
    ?>
    <form class="form" method="post">
        <div class="rc">
            <p><label>Current Balance</label> <b><s>N</s><?= number_format($_SESSION['balance'], 2); ?></b></p>
            <p><label>Plan</label>
                <select class="txt iwdt" name="plan">
                <?php
                $r = $db->get_results("select id, name, cost from plans where id > 1");
                foreach ($r as $v) {
                    list ($id, $name, $cost) = $v;
                    echo '<option value="'.$id.'"';
                    echo $id == $_SESSION['plan'] ? ' selected="selected"' : '';
                    echo '>'.$name.' for N'.$cost.'</option>';
                }
                ?>
                </select>
                <select class="txt iwdt" name="period">
                    <option value="">Select Period</option>
                    <?php
                    $r = $db->get_results("select id, sub_period from plans_period");
                    foreach ($r as $v) {
                        list ($id, $sub_period) = $v;
                        echo '<option value="'.$id.'"';
                        echo $id == $_SESSION['period'] ? ' selected="selected"' : '';
                        echo '>'.$sub_period.' month(s)</option>';
                    }
                    ?>
                </select>
            </p>
            <p>
                <label>&nbsp;</label> <input type="submit" name="submit" class="button" value="Upgrade" /> or <a href="my-account.php">Cancel</a>
            </p>
        </div>
    </form>
</div>

$plan_expiration = ($plan_expiration = "NULL") ? '30' : '$plan_expiration';

 $today = date("m-d-Y"); 
    $dateDiff = strtotime($plan_expiration) - strtotime($today);
    $Daysleft = floor($dateDiff/(60*60*24));