From e0f2d95a8ef29e00d8798f76d47972b2f430143c Mon Sep 17 00:00:00 2001
From: Joniras <jonas.schaltegger@gmail.com>
Date: Tue, 24 Jun 2025 21:44:08 +0200
Subject: [PATCH 1/5] feat: introduced block_servers

---
 CHANGELOG.md                                  |   1 +
 application/controllers/Caldav.php            | 162 ++++++++++++++++++
 application/controllers/Calendar.php          |  18 ++
 .../language/german/translations_lang.php     |  11 ++
 application/libraries/Caldav_sync.php         |  26 ++-
 .../migrations/061_add_block_servers.php      | 101 +++++++++++
 application/models/Appointments_model.php     |  38 +++-
 application/views/pages/calendar.php          |  27 +++
 assets/css/general.scss                       |   4 +
 assets/js/http/caldav_http_client.js          |  40 +++++
 assets/js/utils/calendar_default_view.js      |  13 +-
 assets/js/utils/calendar_sync.js              | 142 +++++++++++++++
 12 files changed, 575 insertions(+), 8 deletions(-)
 create mode 100644 application/migrations/061_add_block_servers.php

diff --git a/CHANGELOG.md b/CHANGELOG.md
index 4cc09ea251..5cd259190d 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -16,6 +16,7 @@ developers to maintain and readjust their custom modifications on the main proje
 - Update unavailable dates after applying appointment data while rescheduling (#1662)
 - Make sure that any-provider does not include hidden providers while generating availability (#1733)
 - Provide "text" version of the emails in addition to HTML (#1711)
+- Allow several "block"-servers to be defined for each provider (to allow multiple calendars to be synced)
 
 
 ## [1.5.1] - 2025-01-20
diff --git a/application/controllers/Caldav.php b/application/controllers/Caldav.php
index 905aa9f136..f2ebca300a 100644
--- a/application/controllers/Caldav.php
+++ b/application/controllers/Caldav.php
@@ -81,6 +81,76 @@ public function connect_to_server(): void
         }
     }
 
+    
+    /**
+     * Connect to the target CalDAV server
+     *
+     * @return void
+     */
+    public function add_block_server(): void
+    {
+        try {
+            $provider_id = request('provider_id');
+            $user_id = session('user_id');
+
+            if (cannot('edit', PRIV_USERS) && (int) $user_id !== (int) $provider_id) {
+                throw new RuntimeException('You do not have the required permissions for this task.');
+            }
+
+            $caldav_url = request('caldav_url');
+            $caldav_username = request('caldav_username');
+            $caldav_password = request('caldav_password');
+
+            $this->caldav_sync->test_connection($caldav_url, $caldav_username, $caldav_password);
+
+            // Insert into caldav_block_servers
+            $this->db->insert('ea_caldav_block_servers', [
+                'user_id' => $provider_id,
+                'caldav_url' => $caldav_url,
+                'caldav_username' => $caldav_username,
+                'caldav_password' => $caldav_password,
+            ]);
+
+            json_response([
+                'success' => true,
+            ]);
+        } catch (GuzzleException | InvalidArgumentException $e) {
+            json_response([
+                'success' => false,
+                'message' => $e->getMessage(),
+            ]);
+        } catch (Throwable $e) {
+            json_exception($e);
+        }
+    }
+
+    public function delete_block_server(): void{
+        try{
+            
+            $provider_id = request('provider_id');
+            $block_server_id = request('block_server_id');
+            $user_id = session('user_id');
+            if (cannot('edit', PRIV_USERS) && (int) $user_id !== (int) $provider_id) {
+                throw new RuntimeException('You do not have the required permissions for this task.');
+            }
+
+            // Delete all appointments associated with this block server and provider
+            $this->db->where('id_caldav_block_server', $block_server_id)
+                     ->where('id_users_provider', $provider_id)
+                     ->delete('ea_appointments');
+
+            // Delete the block server itself
+            $this->db->where('id', $block_server_id)
+                     ->delete('ea_caldav_block_servers');
+
+            json_response([
+                'success' => true,
+            ]);
+        }catch (Throwable $e) {
+            json_exception($e);
+        }
+    }
+
     /**
      * Sync the provider events with the remote CalDAV calendar.
      *
@@ -143,6 +213,7 @@ public static function sync(string $provider_id): void
         $where = [
             'start_datetime >=' => $start_date_time,
             'end_datetime <=' => $end_date_time,
+            'read_only =' => '0',
             'id_users_provider' => $provider['id'],
         ];
 
@@ -334,4 +405,95 @@ public function disable_provider_sync(): void
             json_exception($e);
         }
     }
+
+    /**
+     * Sync events from block servers
+     *
+     * @return void
+     */
+    public function sync_block_servers(): void
+    {
+        $provider_id = request('provider_id');
+        $user_id = session('user_id');
+        if (cannot('edit', PRIV_USERS) && (int) $user_id !== (int) $provider_id) {
+            throw new RuntimeException('You do not have the required permissions for this task.');
+        }
+
+        $block_servers = $this->db->get_where('caldav_block_servers', ['user_id' => $provider_id])->result_array();
+
+        foreach ($block_servers as $block_server) {
+            $this->load->library('caldav_sync');
+            $start_date_time = date('Y-m-d 00:00:00');
+            $end_date_time = date('Y-m-d 23:59:59', strtotime('+30 days'));
+
+            $provider = $this->providers_model->find($provider_id);
+
+            // Use block server credentials for sync
+            $events = $this->caldav_sync->get_sync_events([
+                'settings' => [
+                    'caldav_url' => $block_server['caldav_url'],
+                    'caldav_username' => $block_server['caldav_username'],
+                    'caldav_password' => $block_server['caldav_password'],
+                    'caldav_sync' => true,
+                ],
+                'timezone' => $provider['timezone'],
+                'id' => $provider_id,
+            ], $start_date_time, $end_date_time);
+
+            // Collect current CalDAV event IDs
+            $current_event_ids = array_column($events, 'id');
+
+            // Fetch all read-only appointments for this block server and provider
+            $existing_appointments = $this->appointments_model->get_blocker([
+                'id_caldav_block_server' => $block_server['id'],
+                'id_users_provider' => $provider_id,
+            ]);
+
+            // Delete appointments not present in CalDAV anymore
+            foreach ($existing_appointments as $appointment) {
+                if (!in_array($appointment['id_caldav_calendar'], $current_event_ids)) {
+                    $this->appointments_model->delete($appointment['id']);
+                }
+            }
+
+            // Add or update current events
+            foreach ($events as $event) {
+                $exists = $this->appointments_model->get_blocker([
+                    'id_caldav_calendar' => $event['id'],
+                    'id_caldav_block_server' => $block_server['id'],
+                ]);
+                if ($exists ) {
+                    
+                $is_different =
+                    $exists[0]['start_datetime'] !== $event['start_datetime'] ||
+                    $exists[0]['end_datetime'] !== $event['end_datetime'];
+                    if ($is_different) {
+                        $exists[0]['start_datetime'] = $event['start_datetime'];
+                        $exists[0]['end_datetime'] = $event['end_datetime'];
+                        $exists[0]['is_blocker'] = true;
+                        $this->appointments_model->save($exists[0]);
+                    }
+                    continue; // Event already exists, skip to the next one.
+                }
+
+                $this->appointments_model->save([
+                    'start_datetime' => $event['start_datetime'],
+                    'end_datetime' => $event['end_datetime'],
+                    'location' => $event['location'],
+                    'notes' => $event['summary'] . ';$;' . $event['description'],
+                    'id_users_provider' => $provider_id,
+                    'id_services' => null,
+                    'id_users_customer' => null,
+                    'id_caldav_calendar' => $event['id'],
+                    'is_unavailability' => true,
+                    'read_only' => true,
+                    'id_caldav_block_server' => $block_server['id'],
+                    'is_blocker' => true,
+                    'status' => 'CONFIRMED',
+                ]);
+            }
+        }
+
+        json_response(['success' => true]);
+    }
 }
diff --git a/application/controllers/Calendar.php b/application/controllers/Calendar.php
index d55a2a64ee..19a4b57648 100644
--- a/application/controllers/Calendar.php
+++ b/application/controllers/Calendar.php
@@ -174,6 +174,23 @@ public function index(string $appointment_hash = ''): void
 
         $appointment_status_options = setting('appointment_status_options');
 
+        // Query all block_servers for this provider
+        $block_servers = [];
+        if ($role_slug === DB_SLUG_PROVIDER) {
+            $block_servers = $this->blocked_periods_model->get(['user_id' => $user_id]);
+        } elseif ($role_slug === DB_SLUG_SECRETARY || $role_slug === DB_SLUG_ADMIN) {
+            // For secretaries, get blocked periods for all their providers
+            foreach ($available_providers as $provider_id) {
+            $block_servers = array_merge(
+                $block_servers,
+                        $block_servers = $this->db->get_where('caldav_block_servers', ['user_id' => $provider_id['id']])->result_array()
+            );
+            }
+        } else {
+            // For admins or others, get all blocked periods
+            $block_servers = $this->blocked_periods_model->get();
+        }
+
         script_vars([
             'user_id' => $user_id,
             'role_slug' => $role_slug,
@@ -188,6 +205,7 @@ public function index(string $appointment_hash = ''): void
             'available_services' => $available_services,
             'secretary_providers' => $secretary_providers,
             'edit_appointment' => $edit_appointment,
+            'block_servers' => $block_servers,
             'google_sync_feature' => config('google_sync_feature'),
             'customers' => $this->customers_model->get(null, 50, null, 'update_datetime DESC'),
             'default_language' => setting('default_language'),
diff --git a/application/language/german/translations_lang.php b/application/language/german/translations_lang.php
index ea756a2cc4..dcf32b16cc 100755
--- a/application/language/german/translations_lang.php
+++ b/application/language/german/translations_lang.php
@@ -63,10 +63,17 @@
 $lang['synchronize'] = 'Synchronisieren';
 $lang['enable_sync'] = 'Synchronisation einschalten';
 $lang['disable_sync'] = 'Synchronisation ausschalten';
+$lang['add_block_sync'] = 'Neue Block-Synchronisation hinzufügen';
+$lang['sync_block_servers'] = 'Block-Kalender synchronisieren';
+$lang['blocker_server_list'] = 'Block-Server Liste';
+$lang['delete_block_server'] = 'Willst du den Block-Server löschen?';
+$lang['block_server_deletion_failed'] = 'Block Server konnte nicht gelöscht werden.';
+$lang['block_server_deletion_success'] = 'Block Server erfolgreich gelöscht.';
 $lang['disable_sync_prompt'] = 'Sind Sie sicher, dass Sie die Kalendersynchronisation abschalten wollen?';
 $lang['reload'] = 'Neu laden';
 $lang['appointment'] = 'Termin';
 $lang['unavailability'] = 'Nichtverfügbarkeit';
+$lang['blocker'] = 'Blocker';
 $lang['week'] = 'Woche';
 $lang['month'] = 'Monat';
 $lang['today'] = 'Heute';
@@ -230,6 +237,8 @@
 $lang['unexpected_issues_occurred'] = 'Unerwartete Probleme aufgetreten.';
 $lang['service_communication_error'] = 'Während der Kommunikation mit dem Server ist ein Fehler aufgetreten, bitte versuchen Sie es erneut.';
 $lang['no_privileges_edit_appointments'] = 'Sie haben nicht die Berechtigung, um Termine zu bearbeiten.';
+$lang['blocker_cannot_be_edited'] = 'Termine aus Blocker-Kalender können nicht bearbeitet werden.';
+$lang['blocker_cannot_be_moved'] = 'Termine aus Block-Kalender sind nur zum ansehen, nicht zum bearbeiten.';
 $lang['unavailability_updated'] = 'Nichtverfügbarkeit erfolgreich erneuert worden.';
 $lang['appointments'] = 'Termine';
 $lang['unexpected_warnings'] = 'Unerwartete Warnungen';
@@ -268,6 +277,7 @@
 $lang['select_sync_calendar'] = 'Wählen Sie externe Kalender';
 $lang['select_sync_calendar_prompt'] = 'Wählen Sie den Kalender, mit dem Sie Ihre Termine synchronisieren möchten. Wenn Sie das nicht wollen, wird ein Standard-Kalender verwendet.';
 $lang['sync_calendar_selected'] = 'Externe-Kalender wurde erfolgreich ausgewählt.';
+$lang['sync_block_calendar_selected'] = 'Block Kalender wurden erfolgreich synchronisiert.';
 $lang['oops_something_went_wrong'] = 'Oops! Etwas ist schiefgelaufen.';
 $lang['ea_update_success'] = 'Easy!Appointments wurde erfolgreich aktualisiert.';
 $lang['require_captcha'] = 'CAPTCHA erfordern';
@@ -460,6 +470,7 @@
 $lang['sync_method_prompt'] = 'Welche Synchronisierungsmethode möchten Sie verwenden?';
 $lang['caldav_server'] = 'CalDAV-Server';
 $lang['caldav_connection_info_prompt'] = 'Bitte geben Sie die Verbindungsinformationen des CalDAV-Zielservers ein.';
+$lang['caldav_connection_info_prompt_block_only'] = 'Bitte geben Sie die Verbindungsinformationen des CalDAV-Servers ein, von dem nur Termine runtersynchronisiert werden ein (read-only).';
 $lang['connect'] = 'Verbinden';
 $lang['ldap'] = 'LDAP';
 $lang['ldap_info'] = 'Diese Integration ermöglicht es Ihnen, sich mit einem bestehenden LDAP-Server zu verbinden und Benutzer automatisch in Easy!Appointments zu importieren und ihnen ein SSO mit ihrem Verzeichnispasswort zu ermöglichen (der Benutzername muss übereinstimmen).';
diff --git a/application/libraries/Caldav_sync.php b/application/libraries/Caldav_sync.php
index 34fe9e9380..9fee1caa18 100644
--- a/application/libraries/Caldav_sync.php
+++ b/application/libraries/Caldav_sync.php
@@ -194,8 +194,30 @@ public function get_event(array $provider, string $caldav_event_id): ?array
     public function get_sync_events(array $provider, string $start_date_time, string $end_date_time): array
     {
         try {
-            $client = $this->get_http_client_by_provider_id($provider['id']);
-            $provider_timezone_object = new DateTimeZone($provider['timezone']);
+             // Support both provider and block server parameter structures
+            if (isset($provider['settings'])) {
+                $settings = $provider['settings'];
+                $caldav_url = $settings['caldav_url'] ?? null;
+                $caldav_username = $settings['caldav_username'] ?? null;
+                $caldav_password = $settings['caldav_password'] ?? null;
+            } else {
+                $caldav_url = $provider['caldav_url'] ?? null;
+                $caldav_username = $provider['caldav_username'] ?? null;
+                $caldav_password = $provider['caldav_password'] ?? null;
+            }
+
+            // Timezone
+            $timezone = $provider['timezone'] ?? ($provider['settings']['timezone'] ?? 'UTC');
+            $provider_timezone_object = new DateTimeZone($timezone);
+
+            // Use credentials directly if present, otherwise fallback to provider ID
+            if ($caldav_url && $caldav_username && $caldav_password) {
+                $client = $this->get_http_client($caldav_url, $caldav_username, $caldav_password);
+            } elseif (isset($provider['id'])) {
+                $client = $this->get_http_client_by_provider_id($provider['id']);
+            } else {
+                throw new InvalidArgumentException('Missing CalDAV credentials or provider ID.');
+            }
 
             $response = $this->fetch_events($client, $start_date_time, $end_date_time);
 
diff --git a/application/migrations/061_add_block_servers.php b/application/migrations/061_add_block_servers.php
new file mode 100644
index 0000000000..117e523710
--- /dev/null
+++ b/application/migrations/061_add_block_servers.php
@@ -0,0 +1,101 @@
+<?php defined('BASEPATH') or exit('No direct script access allowed');
+
+/* ----------------------------------------------------------------------------
+ * Easy!Appointments - Online Appointment Scheduler
+ *
+ * @package     EasyAppointments
+ * @author      A.Tselegidis <alextselegidis@gmail.com>
+ * @copyright   Copyright (c) Alex Tselegidis
+ * @license     https://opensource.org/licenses/GPL-3.0 - GPLv3
+ * @link        https://easyappointments.org
+ * @since       v1.4.0
+ * ---------------------------------------------------------------------------- */
+
+
+class Migration_Add_caldav_block_servers_table_and_appointment_columns extends EA_Migration
+{
+    /**
+     * Upgrade method.
+     */
+    public function up(): void
+    {
+        if (!$this->db->table_exists('caldav_block_servers')) {
+            $this->dbforge->add_field( [
+                'id' => [
+                    'type' => 'INT',
+                    'auto_increment' => true
+                ],
+                'user_id' => [
+                    'type' => 'INT',
+                    'null' => false
+                ],
+                'caldav_url' => [
+                    'type' => 'VARCHAR',
+                    'constraint' => '255',
+                    'null' => false
+                ],
+                'caldav_username' => [
+                    'type' => 'VARCHAR',
+                    'constraint' => '255',
+                    'null' => false
+                ],
+                'caldav_password' => [
+                    'type' => 'VARCHAR',
+                    'constraint' => '255',
+                    'null' => false
+                ],
+                'created_at' => [
+                    'type' => 'DATETIME',
+                    'null' => false,
+                    'default' => 'CURRENT_TIMESTAMP'
+                ]
+            ]);
+
+            $this->dbforge->add_key('id', true);
+            $this->dbforge->add_key('user_id');
+            $this->dbforge->create_table('caldav_block_servers', true,['engine' => 'InnoDB']);
+
+            $this->db->query('ALTER TABLE ' . $this->db->dbprefix('caldav_block_servers') . ' ADD CONSTRAINT fk_caldav_block_servers_user_id FOREIGN KEY (user_id) REFERENCES ' . $this->db->dbprefix('users') . '(id) ON DELETE CASCADE');
+        }
+
+        if (!$this->db->field_exists('read_only', 'appointments')) {
+            $fields = [
+                'read_only' => [
+                    'type' => 'BOOLEAN',
+                    'null' => false,
+                    'default' => 0
+                ]
+            ];
+            $this->dbforge->add_column('appointments', $fields);
+        }
+
+        if (!$this->db->field_exists('id_caldav_block_server', 'appointments')) {
+            $fields = [
+                'id_caldav_block_server' => [
+                    'type' => 'INT',
+                    'null' => true,
+                    'after' => 'read_only'
+                ]
+            ];
+            $this->dbforge->add_column('appointments', $fields);
+        }
+    }
+
+    /**
+     * Downgrade method.
+     */
+    public function down(): void
+    {
+        if ($this->db->field_exists('id_caldav_block_server', 'appointments')) {
+            $this->dbforge->drop_column('appointments', 'id_caldav_block_server');
+        }
+
+        if ($this->db->field_exists('read_only', 'appointments')) {
+            $this->dbforge->drop_column('appointments', 'read_only');
+        }
+
+        if ($this->db->table_exists('caldav_block_servers')) {
+            $this->dbforge->drop_table('caldav_block_servers');
+        }
+    }
+}
\ No newline at end of file
diff --git a/application/models/Appointments_model.php b/application/models/Appointments_model.php
index f040e49d9c..5663526e8d 100644
--- a/application/models/Appointments_model.php
+++ b/application/models/Appointments_model.php
@@ -27,6 +27,8 @@ class Appointments_model extends EA_Model
         'id_users_provider' => 'integer',
         'id_users_customer' => 'integer',
         'id_services' => 'integer',
+        'read_only' => 'boolean',
+        'id_caldav_block_server' => 'integer', // <-- Add this line
     ];
 
     /**
@@ -61,7 +63,8 @@ class Appointments_model extends EA_Model
     public function save(array $appointment): int
     {
         $this->validate($appointment);
-
+        //remove is_blocker from appointment data
+        unset($appointment['is_blocker']);
         if (empty($appointment['id'])) {
             return $this->insert($appointment);
         } else {
@@ -92,14 +95,14 @@ public function validate(array $appointment): void
         // Make sure all required fields are provided.
 
         $require_notes = filter_var(setting('require_notes'), FILTER_VALIDATE_BOOLEAN);
-
-        if (
+        $isBlocker = isset($appointment['is_blocker'])?(bool)$appointment['is_blocker']:false;
+        if ( !$isBlocker && (
             empty($appointment['start_datetime']) ||
             empty($appointment['end_datetime']) ||
             empty($appointment['id_services']) ||
             empty($appointment['id_users_provider']) ||
             empty($appointment['id_users_customer']) ||
-            (empty($appointment['notes']) && $require_notes)
+            (empty($appointment['notes']) && $require_notes))
         ) {
             throw new InvalidArgumentException('Not all required fields are provided: ' . print_r($appointment, true));
         }
@@ -132,7 +135,7 @@ public function validate(array $appointment): void
             ->get()
             ->num_rows();
 
-        if (!$count) {
+        if (!$count && !$isBlocker) {
             throw new InvalidArgumentException(
                 'The appointment provider ID was not found in the database: ' . $appointment['id_users_provider'],
             );
@@ -199,6 +202,31 @@ public function get(
         return $appointments;
     }
 
+    public function get_blocker(
+        array|string|null $where = null,
+        ?int $limit = null,
+        ?int $offset = null,
+        ?string $order_by = null,
+    ): array {
+        if ($where !== null) {
+            $this->db->where($where);
+        }
+
+        if ($order_by) {
+            $this->db->order_by($this->db->escape($order_by));
+        }
+
+        $appointments = $this->db
+            ->get_where('appointments', null, $limit, $offset)
+            ->result_array();
+
+        foreach ($appointments as &$appointment) {
+            $this->cast($appointment);
+        }
+
+        return $appointments;
+    }
+
     /**
      * Insert a new appointment into the database.
      *
diff --git a/application/views/pages/calendar.php b/application/views/pages/calendar.php
index a5aaab164c..6b16851b15 100755
--- a/application/views/pages/calendar.php
+++ b/application/views/pages/calendar.php
@@ -49,6 +49,33 @@ class="btn btn-light"
             <?php endif; ?>
 
             <?php if (can('add', PRIV_APPOINTMENTS)): ?>
+                <div class="dropdown d-sm-inline-block">
+                    <button class="btn btn-light" type="button" title="<?= lang('blocker') ?>" data-bs-toggle="dropdown">
+                        <i class="fas fa-hand"></i>
+                    </button>
+                    <ul class="dropdown-menu">
+                        <li>
+                            <a class="dropdown-item" href="#" id="add-block-sync">
+                                <?= lang('add_block_sync') ?>
+                            </a>
+                        </li>
+                        <li>
+                            <a class="dropdown-item" href="#" id="sync-block-servers">
+                                <?= lang('sync_block_servers') ?>
+                            </a>
+                        </li>
+                        <li>
+                            <span class="dropdown-header"><?= lang('blocker_server_list')  ?> (Reload to refresh)</s>
+                        </li>
+                        <?php foreach (vars('block_servers') as $server): ?>
+                            <li>
+                                <a class="dropdown-item block-server" href="#" data-server_id="<?= $server['id'] ?>">
+                                    <?= $server['id'].' : <span class="server-url">'.$server['caldav_url'].'</span>'  ?>
+                                </a>
+                            </li>
+                        <?php endforeach; ?>
+                    </ul>
+                </div>
                 <div class="dropdown d-sm-inline-block">
                     <button class="btn btn-light" type="button" data-bs-toggle="dropdown">
                         <i class="fas fa-plus-square"></i>
diff --git a/assets/css/general.scss b/assets/css/general.scss
index 3e607c60ae..6e2dd1b8a6 100644
--- a/assets/css/general.scss
+++ b/assets/css/general.scss
@@ -515,3 +515,7 @@ body .clearfix {
 .cc-window {
     z-index: 999 !important;
 }
+
+.server-url{
+    text-transform: lowercase;
+}
\ No newline at end of file
diff --git a/assets/js/http/caldav_http_client.js b/assets/js/http/caldav_http_client.js
index b9e84dcf9f..5473d41b41 100644
--- a/assets/js/http/caldav_http_client.js
+++ b/assets/js/http/caldav_http_client.js
@@ -98,11 +98,51 @@ App.Http.Caldav = (function () {
         return $.post(url, data);
     }
 
+    function addBlockServer(providerId, caldavUrl, caldavUsername, caldavPassword) {
+        const url = App.Utils.Url.siteUrl('caldav/add_block_server');
+
+        const data = {
+            csrf_token: vars('csrf_token'),
+            provider_id: providerId,
+            caldav_url: caldavUrl,
+            caldav_username: caldavUsername,
+            caldav_password: caldavPassword,
+        };
+
+        return $.post(url, data);
+    }
+
+    function deleteBlockServer(providerId, blockServerId) {
+        const url = App.Utils.Url.siteUrl('caldav/delete_block_server');
+
+        const data = {
+            csrf_token: vars('csrf_token'),
+            provider_id: providerId,
+            block_server_id: blockServerId,
+        };
+
+        return $.post(url, data);
+    }
+
+    function syncBlockServers(providerId) {
+        const url = App.Utils.Url.siteUrl('caldav/sync_block_servers');
+
+        const data = {
+            csrf_token: vars('csrf_token'),
+            provider_id: providerId,
+        };
+
+        return $.post(url, data);
+    }
+
     return {
         getCaldavCalendars,
         selectCaldavCalendar,
         disableProviderSync,
         syncWithCaldav,
         connectToServer,
+        addBlockServer,
+        syncBlockServers,
+        deleteBlockServer,
     };
 })();
diff --git a/assets/js/utils/calendar_default_view.js b/assets/js/utils/calendar_default_view.js
index cc5e3ea94a..ae5f0b8ea0 100755
--- a/assets/js/utils/calendar_default_view.js
+++ b/assets/js/utils/calendar_default_view.js
@@ -366,6 +366,11 @@ App.Utils.CalendarDefaultView = (function () {
             $popoverTarget.popover('dispose');
         }
 
+        if(info.event.extendedProps.data.read_only == "1" ){
+            App.Layouts.Backend.displayNotification(lang('blocker_cannot_be_edited'));
+            return;
+        }
+
         let $html;
         let displayEdit;
         let displayDelete;
@@ -933,6 +938,12 @@ App.Utils.CalendarDefaultView = (function () {
             return;
         }
 
+        if(info.event.extendedProps.data.read_only == "1" ){
+            info.revert();
+            App.Layouts.Backend.displayNotification(lang('blocker_cannot_be_moved'));
+            return;
+        }
+
         if ($notification.is(':visible')) {
             $notification.hide('bind');
         }
@@ -1241,7 +1252,7 @@ App.Utils.CalendarDefaultView = (function () {
                     }
 
                     const unavailabilityEvent = {
-                        title: lang('unavailability') + notes,
+                        title: (unavailability.read_only=="1"?lang('blocker'):lang('unavailability'))+(unavailability.id_caldav_block_server	?( " ("+unavailability.id_caldav_block_server+")"):"") + notes,
                         start: moment(unavailability.start_datetime).toDate(),
                         end: moment(unavailability.end_datetime).toDate(),
                         allDay: false,
diff --git a/assets/js/utils/calendar_sync.js b/assets/js/utils/calendar_sync.js
index 09600c8354..250e3264e8 100644
--- a/assets/js/utils/calendar_sync.js
+++ b/assets/js/utils/calendar_sync.js
@@ -20,9 +20,12 @@ App.Utils.CalendarSync = (function () {
     const $selectFilterItem = $('#select-filter-item');
     const $enableSync = $('#enable-sync');
     const $disableSync = $('#disable-sync');
+    const $addBlockSync = $('#add-block-sync');
+    const $syncBlockServers = $('#sync-block-servers');
     const $triggerSync = $('#trigger-sync');
     const $syncButtonGroup = $('#sync-button-group');
     const $reloadAppointments = $('#reload-appointments');
+    const $blockServers = $('.block-server');
 
     const FILTER_TYPE_PROVIDER = 'provider';
     let isSyncing = false;
@@ -362,6 +365,113 @@ App.Utils.CalendarSync = (function () {
         ]);
     }
 
+    function onAddBlockSyncClick() {
+        let defaultCaldavUrl = '',
+            defaultCaldavUsername = '',
+            defaultCaldavPassword = '';
+        const $container = $(`
+            <div>
+                <div class="mb-3">
+                    <label for="caldav-url" class="form-label">
+                        ${lang('calendar_url')}
+                    </label>
+                    <input type="text" class="form-control" id="caldav-url" value="${defaultCaldavUrl}"/>
+                </div> 
+                <div class="mb-3">
+                    <label for="caldav-username" class="form-label">
+                        ${lang('username')}
+                    </label>
+                    <input type="text" class="form-control" id="caldav-username" value="${defaultCaldavUsername}"/>
+                </div> 
+                <div class="mb-3">
+                    <label for="caldav-password" class="form-label">
+                        ${lang('password')}
+                    </label>
+                    <input type="password" class="form-control" id="caldav-password" value="${defaultCaldavPassword}"/>
+                </div>    
+                
+                <div class="alert alert-danger" hidden>
+                    <!-- JS -->
+                </div>
+            </div>
+        `);
+
+        const $messageModal = App.Utils.Message.show(
+            lang('add_block_sync'),
+            lang('caldav_connection_info_prompt_block_only'),
+            [
+                {
+                    text: lang('cancel'),
+                    click: (event, messageModal) => {
+                        messageModal.hide();
+                    },
+                },
+                {
+                    text: lang('connect'),
+                    click: (event, messageModal) => {
+                        const providerId = $selectFilterItem.val();
+
+                        $messageModal.find('.is-invalid').removeClass('is-invalid');
+
+                        const $alert = $messageModal.find('.alert');
+                        $alert.text('').prop('hidden', true);
+
+                        const $caldavUrl = $container.find('#caldav-url');
+                        const caldavUrl = $caldavUrl.val();
+
+                        if (!caldavUrl) {
+                            $caldavUrl.addClass('is-invalid');
+                            return;
+                        }
+
+                        const $caldavUsername = $container.find('#caldav-username');
+                        const caldavUsername = $caldavUsername.val();
+
+                        if (!caldavUsername) {
+                            $caldavUsername.addClass('is-invalid');
+                            return;
+                        }
+
+                        const $caldavPassword = $container.find('#caldav-password');
+                        const caldavPassword = $caldavPassword.val();
+
+                        if (!caldavPassword) {
+                            $caldavPassword.addClass('is-invalid');
+                            return;
+                        }
+
+                        App.Http.Caldav.addBlockServer(providerId, caldavUrl, caldavUsername, caldavPassword).done(
+                            (response) => {
+                                if (!response.success) {
+                                    $caldavUrl.addClass('is-invalid');
+                                    $caldavUsername.addClass('is-invalid');
+                                    $caldavPassword.addClass('is-invalid');
+
+                                    $alert.text(lang('login_failed') + ' ' + response.message).prop('hidden', false);
+
+                                    return;
+                                }
+
+                                const $selectedOption = $selectFilterItem.find('option:selected');
+
+                                $selectedOption.attr('caldav-sync', '1');
+
+                                updateSyncButtons();
+                                $syncBlockServers.trigger('click');
+
+                                App.Layouts.Backend.displayNotification(lang('sync_calendar_selected'));
+
+                                messageModal.hide();
+                            },
+                        );
+                    },
+                },
+            ],
+        );
+
+        $messageModal.find('.modal-body').append($container);
+    }
+
     function onDisableSyncClick() {
         const hasGoogleSync = hasSync('google');
 
@@ -377,6 +487,33 @@ App.Utils.CalendarSync = (function () {
         }
     }
 
+    function onSyncBlockServersClick() {
+        const providerId = $selectFilterItem.val();
+        App.Http.Caldav.syncBlockServers(providerId).done((response) => {
+            if (!response.success) {
+                $alert.text(lang('calendar_sync_failed') + ' ' + response.message).prop('hidden', false);
+                return;
+            }
+            $reloadAppointments.trigger('click');
+            App.Layouts.Backend.displayNotification(lang('sync_block_calendar_selected'));
+        });
+    }
+    function onBlockServerClick($event) {
+        const providerId = $selectFilterItem.val();
+        console.log($($event.currentTarget).data());
+        if(confirm(lang('delete_block_server'))) {
+        App.Http.Caldav.deleteBlockServer(providerId,$($event.currentTarget).data().server_id).done((response) => {
+            if (!response.success) {
+                $alert.text(lang('block_server_deletion_failed') + ' ' + response.message).prop('hidden', false);
+
+                return;
+            }
+            $syncBlockServers.trigger('click');
+            App.Layouts.Backend.displayNotification(lang('block_server_deletion_success'));
+        });
+    }
+}
+
     function onTriggerSyncClick() {
         const hasGoogleSync = hasSync('google');
         isSyncing = true;
@@ -404,8 +541,13 @@ App.Utils.CalendarSync = (function () {
         $selectFilterItem.on('change', onSelectFilterItemChange);
         $enableSync.on('click', onEnableSyncClick);
         $disableSync.on('click', onDisableSyncClick);
+        $addBlockSync.on('click', onAddBlockSyncClick);
+        $syncBlockServers.on('click', onSyncBlockServersClick);
         $triggerSync.on('click', onTriggerSyncClick);
         updateSyncButtons();
+        $blockServers.each((index,blockServer) => {
+            $(blockServer).on('click', onBlockServerClick)
+        });
     }
 
     document.addEventListener('DOMContentLoaded', initialize);

From c97eafcff9651e204262600944e1c50baf043788 Mon Sep 17 00:00:00 2001
From: Joniras <jonas.schaltegger@gmail.com>
Date: Sun, 27 Jul 2025 18:30:07 +0200
Subject: [PATCH 2/5] feat: make sync function static to be called in Console

---
 application/controllers/Caldav.php   | 30 +++++++++++++++++-----------
 application/controllers/Console.php  |  1 +
 assets/js/http/caldav_http_client.js |  2 +-
 3 files changed, 20 insertions(+), 13 deletions(-)

diff --git a/application/controllers/Caldav.php b/application/controllers/Caldav.php
index f2ebca300a..3cbd0ee983 100644
--- a/application/controllers/Caldav.php
+++ b/application/controllers/Caldav.php
@@ -411,25 +411,31 @@ public function disable_provider_sync(): void
      *
      * @return void
      */
-    public function sync_block_servers(): void
+    public static function sync_block_servers(string $provider_id): void
     {
-        $provider_id = request('provider_id');
+        /** @var EA_Controller $CI */
+        $CI = get_instance();
+
+
+        $CI->load->library('caldav_sync');
+        $CI->load->model('providers_model');
+        $CI->load->model('appointments_model');
+        $db = $CI->load->database('', true);
         $user_id = session('user_id');
         if (cannot('edit', PRIV_USERS) && (int) $user_id !== (int) $provider_id) {
             throw new RuntimeException('You do not have the required permissions for this task.');
         }
 
-        $block_servers = $this->db->get_where('caldav_block_servers', ['user_id' => $provider_id])->result_array();
+        $block_servers = $db->get_where('caldav_block_servers', ['user_id' => $provider_id])->result_array();
 
         foreach ($block_servers as $block_server) {
-            $this->load->library('caldav_sync');
             $start_date_time = date('Y-m-d 00:00:00');
             $end_date_time = date('Y-m-d 23:59:59', strtotime('+30 days'));
 
-            $provider = $this->providers_model->find($provider_id);
+            $provider = $CI->providers_model->find($provider_id);
 
             // Use block server credentials for sync
-            $events = $this->caldav_sync->get_sync_events([
+            $events = $CI->caldav_sync->get_sync_events([
                 'settings' => [
                     'caldav_url' => $block_server['caldav_url'],
                     'caldav_username' => $block_server['caldav_username'],
@@ -444,7 +450,7 @@ public function sync_block_servers(): void
             $current_event_ids = array_column($events, 'id');
 
             // Fetch all read-only appointments for this block server and provider
-            $existing_appointments = $this->appointments_model->get_blocker([
+            $existing_appointments = $CI->appointments_model->get_blocker([
                 'id_caldav_block_server' => $block_server['id'],
                 'id_users_provider' => $provider_id,
             ]);
@@ -452,13 +458,13 @@ public function sync_block_servers(): void
             // Delete appointments not present in CalDAV anymore
             foreach ($existing_appointments as $appointment) {
                 if (!in_array($appointment['id_caldav_calendar'], $current_event_ids)) {
-                    $this->appointments_model->delete($appointment['id']);
+                    $CI->appointments_model->delete($appointment['id']);
                 }
             }
 
             // Add or update current events
             foreach ($events as $event) {
-                $exists = $this->appointments_model->get_blocker([
+                $exists = $CI->appointments_model->get_blocker([
                     'id_caldav_calendar' => $event['id'],
                     'id_caldav_block_server' => $block_server['id'],
                 ]);
@@ -471,16 +477,16 @@ public function sync_block_servers(): void
                         $exists[0]['start_datetime'] = $event['start_datetime'];
                         $exists[0]['end_datetime'] = $event['end_datetime'];
                         $exists[0]['is_blocker'] = true;
-                        $this->appointments_model->save($exists[0]);
+                        $CI->appointments_model->save($exists[0]);
                     }
                     continue; // Event already exists, skip to the next one.
                 }
 
-                $this->appointments_model->save([
+                $CI->appointments_model->save([
                     'start_datetime' => $event['start_datetime'],
                     'end_datetime' => $event['end_datetime'],
                     'location' => $event['location'],
-                    'notes' => $event['summary'] . ';$;' . $event['description'],
+                    'notes' => $event['summary'],
                     'id_users_provider' => $provider_id,
                     'id_services' => null,
                     'id_users_customer' => null,
diff --git a/application/controllers/Console.php b/application/controllers/Console.php
index efa6954972..a59213cea8 100644
--- a/application/controllers/Console.php
+++ b/application/controllers/Console.php
@@ -151,6 +151,7 @@ public function sync(): void
 
             if (filter_var($provider['settings']['caldav_sync'], FILTER_VALIDATE_BOOLEAN)) {
                 Caldav::sync((string) $provider['id']);
+                Caldav::sync_block_servers((string) $provider['id']);
             }
         }
     }
diff --git a/assets/js/http/caldav_http_client.js b/assets/js/http/caldav_http_client.js
index 5473d41b41..8137c3eddd 100644
--- a/assets/js/http/caldav_http_client.js
+++ b/assets/js/http/caldav_http_client.js
@@ -125,7 +125,7 @@ App.Http.Caldav = (function () {
     }
 
     function syncBlockServers(providerId) {
-        const url = App.Utils.Url.siteUrl('caldav/sync_block_servers');
+        const url = App.Utils.Url.siteUrl('caldav/sync_block_servers/' + providerId);
 
         const data = {
             csrf_token: vars('csrf_token'),

From 6e9b82dd807765f1320d9e2fefc14ac2657e5775 Mon Sep 17 00:00:00 2001
From: Joniras <jonas.schaltegger@gmail.com>
Date: Fri, 1 Aug 2025 11:54:33 +0200
Subject: [PATCH 3/5] fix: permission error when calling it from cli

---
 application/controllers/Caldav.php | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/application/controllers/Caldav.php b/application/controllers/Caldav.php
index 3cbd0ee983..ac8b66dd8b 100644
--- a/application/controllers/Caldav.php
+++ b/application/controllers/Caldav.php
@@ -422,7 +422,7 @@ public static function sync_block_servers(string $provider_id): void
         $CI->load->model('appointments_model');
         $db = $CI->load->database('', true);
         $user_id = session('user_id');
-        if (cannot('edit', PRIV_USERS) && (int) $user_id !== (int) $provider_id) {
+        if (cannot('edit', PRIV_USERS) && (int) $user_id !== (int) $provider_id  && !is_cli()) {
             throw new RuntimeException('You do not have the required permissions for this task.');
         }
 

From d649aab5cb3c4baec2e7307343746b29960259be Mon Sep 17 00:00:00 2001
From: Joniras <jonas.schaltegger@gmail.com>
Date: Sun, 3 Aug 2025 17:56:36 +0200
Subject: [PATCH 4/5] fix: prevent deletion by delete recurring events function

---
 application/models/Appointments_model.php | 1 +
 1 file changed, 1 insertion(+)

diff --git a/application/models/Appointments_model.php b/application/models/Appointments_model.php
index 5663526e8d..e8a28116ac 100644
--- a/application/models/Appointments_model.php
+++ b/application/models/Appointments_model.php
@@ -381,6 +381,7 @@ public function delete_caldav_recurring_events(string $start_date_time, string $
             ->where('start_datetime >=', $start_date_time)
             ->where('end_datetime <=', $end_date_time)
             ->where('is_unavailability', true)
+            ->where('id_caldav_block_server =', null, false)
             ->like('id_caldav_calendar', 'RECURRENCE')
             ->delete('appointments');
     }

From f06055fda10e887abe438159dfbd8c0204e1272a Mon Sep 17 00:00:00 2001
From: Joniras <jonas.schaltegger@gmail.com>
Date: Sun, 3 Aug 2025 17:56:36 +0200
Subject: [PATCH 5/5] fix: enable sync for providers without caldav_sync and
 rename migration

---
 application/controllers/Console.php              | 2 +-
 application/migrations/061_add_block_servers.php | 2 +-
 2 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/application/controllers/Console.php b/application/controllers/Console.php
index a59213cea8..17d0994d3f 100644
--- a/application/controllers/Console.php
+++ b/application/controllers/Console.php
@@ -151,8 +151,8 @@ public function sync(): void
 
             if (filter_var($provider['settings']['caldav_sync'], FILTER_VALIDATE_BOOLEAN)) {
                 Caldav::sync((string) $provider['id']);
-                Caldav::sync_block_servers((string) $provider['id']);
             }
+            Caldav::sync_block_servers((string) $provider['id']);
         }
     }
 
diff --git a/application/migrations/061_add_block_servers.php b/application/migrations/061_add_block_servers.php
index 117e523710..9e5a8a2dc5 100644
--- a/application/migrations/061_add_block_servers.php
+++ b/application/migrations/061_add_block_servers.php
@@ -12,7 +12,7 @@
  * ---------------------------------------------------------------------------- */
 
 
-class Migration_Add_caldav_block_servers_table_and_appointment_columns extends EA_Migration
+class Migration_Add_block_servers extends EA_Migration
 {
     /**
      * Upgrade method.