Don't allow membership renewals when they aren't near expiration

public/parts/renew.php

@@ -39,6 +39,13 @@ if (empty($IN_SITE)) {
                             case "bademail":
                                 $msg = "That email address doesn't look right.  Please try again.";
                                 break;
+                            case "tooearly":
+                                if (!empty($_GET['exp']) && is_numeric($_GET['exp'])) {
+                                    $msg = "This membership isn't expiring until " . date("F Y", $_GET['exp'] * 1) . " and cannot be renewed yet.";
+                                } else {
+                                    $msg = "This membership isn't close enough to expiration and cannot be renewed yet.";
+                                }
+                                break;
                         }
                     }
                     if ($msg != "") {

public/parts/verify.php

@@ -19,6 +19,15 @@ if (!empty($_POST['email'])) {
         die("We don't have that email on file for any current families.");
     }
 
+    $familyid = $database->get('families', 'familyid', ['email' => strtolower($_POST['email'])]);
+
+    // Check expiration date
+    $expires = (new Family())->load($familyid)->getExpires();
+    if ($expires > strtotime("+6 months")) {
+        header("Location: ./?page=renew&msg=tooearly&exp=$expires");
+        die("This membership isn't expiring until " . date("F Y", $expires) . " and cannot be renewed yet.");
+    }
+
     $code = mt_rand(100000, 999999);
     $_SESSION['code'] = $code;
     $_SESSION['maybefamily'] = $familyid;