Event based invite system (#1149)

Co-authored: @belomaxorka

library/config.php

@@ -378,6 +378,18 @@ $bb_cfg['unique_ip'] = false; // Disallow registration from multiple IP addresse
 $bb_cfg['new_user_reg_restricted'] = false; // Disallow registration in below hours
 $bb_cfg['new_user_reg_interval'] = [0, 1, 2, 3, 4, 5, 6, 7, 8, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23]; // Available hours
 $bb_cfg['reg_email_activation'] = true; // Demand to activate profile by email confirmation
+// Invites
+$bb_cfg['invite_only'] = true;
+// Invite codes
+// Syntax: 'invite_code' => 'validity_period'
+// The 'validity_period' value is based on strtotime() function: https://www.php.net/manual/en/function.strtotime.php
+// Invite link example: site_url/profile.php?mode=register&invite=new_year
+$bb_cfg['invite_codes'] = [
+    'new_year' => '+1 month',
+    'ein_volk' => '29 July 1936',
+    'catch_up_overtake' => '1917-10-09'
+];
+
 $bb_cfg['password_symbols'] = [
     // Whay symbols should be required in the password
     'nums' => true, // Numeric

library/includes/ucp/register.php

@@ -71,6 +71,7 @@ switch ($mode) {
             'username' => true,
             'user_password' => true,
             'user_email' => true,
+            'invite_code' => true,
             'user_timezone' => true,
             'user_lang' => true,
             'user_opt' => true
@@ -81,6 +82,7 @@ switch ($mode) {
             'username' => '',
             'user_password' => '',
             'user_email' => '',
+            'invite_code' => '',
             'user_timezone' => $bb_cfg['board_timezone'],
             'user_lang' => $bb_cfg['default_lang'],
             'user_opt' => 0,
@@ -197,6 +199,25 @@ foreach ($profile_fields as $field => $can_edit) {
             $tp_data['USERNAME'] = $pr_data['username'];
             break;
 
+        /**
+         *  Invite code (reg)
+         */
+        case 'invite_code':
+            if ($bb_cfg['invite_only']) {
+                $invite_code = $_POST['invite_code'] ?? '';
+                if ($submit) {
+                    if (isset($bb_cfg['invite_codes'][$invite_code])) {
+                        if (TIMENOW > strtotime($bb_cfg['invite_codes'][$invite_code])) {
+                            $errors[] = $lang['INVITE_EXPIRED'];
+                        }
+                    }
+                    else {
+                        $errors[] = $lang['INCORRECT_INVITE'];
+                    }
+                }
+            }
+            break;
+
         /**
          *  Пароль (edit, reg)
          */
@@ -660,6 +681,7 @@ $template->assign_vars([
     'ADM_EDIT' => $adm_edit,
     'SHOW_PASS' => ($adm_edit || ($mode == 'register' && IS_ADMIN)),
     'PASSWORD_LONG' => sprintf($lang['PASSWORD_LONG'], PASSWORD_MAX_LENGTH, PASSWORD_MIN_LENGTH),
+    'INVITE_CODE' => !empty($_GET['invite']) ? htmlCHR($_GET['invite']) : '',
     'CAPTCHA_HTML' => ($need_captcha) ? bb_captcha('get') : '',
 
     'LANGUAGE_SELECT' => \TorrentPier\Legacy\Select::language($pr_data['user_lang'], 'user_lang'),

library/language/source/main.php

@@ -688,6 +688,11 @@ $lang['LIKE_OWN_POST'] = 'You can\'t vote for your own topic';
 $lang['NO_LIKES'] = 'Nobody gave a vote yet';
 $lang['LIKE_ALREADY'] = 'You already voted this topic';
 
+// Invites
+$lang['INVITE_CODE'] = 'Invite code';
+$lang['INCORRECT_INVITE'] = 'Invite not found';
+$lang['INVITE_EXPIRED'] = 'Invite expired';
+
 // Group control panel
 $lang['GROUP_CONTROL_PANEL'] = 'User Groups';
 $lang['GROUP_CONFIGURATION'] = 'Group Configuration';

styles/templates/default/usercp_register.tpl

@@ -95,6 +95,12 @@
                 <input id="pass_confirm" onBlur="ajax.exec({ action: 'user_register', mode: 'check_pass', pass: $('#pass').val(), pass_confirm: $('#pass_confirm').val() }); return false;" type="<!-- IF SHOW_PASS -->text<!-- ELSE -->password<!-- ENDIF -->" name="cfm_pass" size="35" maxlength="32" value=""/>&nbsp;<span id="check_pass"></span>
             </td>
         </tr>
+        <!-- IF $bb_cfg['invite_only'] and not EDIT_PROFILE -->
+            <tr>
+                <td class="prof-title">{L_INVITE_CODE}: *</td>
+                <td><input type="text" name="invite_code" size="35" value="{INVITE_CODE}"/></td>
+            </tr>
+        <!-- ENDIF -->
         <!-- IF CAPTCHA_HTML -->
         <tr>
             <td class="prof-title">{L_CAPTCHA}: *</td>