From af38d56c0dabb4c8261e4f658271e3eefd435112 Mon Sep 17 00:00:00 2001
From: olayiwola-compucorp <olayiwola@compucorp.co.uk>
Date: Thu, 30 Sep 2021 13:04:41 +0100
Subject: [PATCH 1/2] Add hooks to alter Mosaico plugins

---
 CRM/Mosaico/Page/Editor.php                 | 23 +++++++++++++++++++++
 templates/CRM/Mosaico/Page/Editor.tpl       |  2 +-
 templates/CRM/Mosaico/Page/EditorIframe.tpl |  2 +-
 3 files changed, 25 insertions(+), 2 deletions(-)

diff --git a/CRM/Mosaico/Page/Editor.php b/CRM/Mosaico/Page/Editor.php
index ec45212922..ec89045f2c 100644
--- a/CRM/Mosaico/Page/Editor.php
+++ b/CRM/Mosaico/Page/Editor.php
@@ -14,6 +14,7 @@ public function run() {
       $this->createMosaicoConfig(),
       defined('JSON_PRETTY_PRINT') ? JSON_PRETTY_PRINT : 0
     ));
+    $smarty->assign('mosaicoPlugins', $this->getMosaicoPlugins());
     echo $smarty->fetch(self::getTemplateFileName());
     CRM_Utils_System::civiExit();
   }
@@ -152,4 +153,26 @@ protected function getMaxFileSize() {
     return (int) min($iniVal, $settingVal);
   }
 
+  /**
+   * Gets the plugins for `Mosaico.init()`.
+   * 
+   * @return array
+   */
+  public function getMosaicoPlugins() {
+    $plugins = [];
+
+    // Allow plugins to be added by a hook.
+    if (class_exists('\Civi\Core\Event\GenericHookEvent')) {
+      \Civi::dispatcher()->dispatch('hook_civicrm_mosaicoPlugin',
+        \Civi\Core\Event\GenericHookEvent::create([
+          'plugins' => &$plugins,
+        ])
+      );
+    }
+
+    $plugins = '[ ' . implode(',', $plugins) . ' ]';
+
+    return $plugins;
+  }
+
 }
diff --git a/templates/CRM/Mosaico/Page/Editor.tpl b/templates/CRM/Mosaico/Page/Editor.tpl
index 0b03b55fa5..edd91a8322 100644
--- a/templates/CRM/Mosaico/Page/Editor.tpl
+++ b/templates/CRM/Mosaico/Page/Editor.tpl
@@ -23,7 +23,7 @@
         return;
       }
 
-      var plugins;
+      var plugins = {/literal}{$mosaicoPlugins}{literal};
       // A basic plugin that expose the "viewModel" object as a global variable.
       // plugins = [function(vm) {window.viewModel = vm;}];
       var config = {/literal}{$mosaicoConfig}{literal};
diff --git a/templates/CRM/Mosaico/Page/EditorIframe.tpl b/templates/CRM/Mosaico/Page/EditorIframe.tpl
index 6e8fd6c758..c2bbd74385 100644
--- a/templates/CRM/Mosaico/Page/EditorIframe.tpl
+++ b/templates/CRM/Mosaico/Page/EditorIframe.tpl
@@ -22,7 +22,7 @@
         return;
       }
 
-      var plugins = [];
+      var plugins = {/literal}{$mosaicoPlugins}{literal};
       var config = {/literal}{$mosaicoConfig}{literal};
       
       window.addEventListener('beforeunload', function(e) {

From a2cf0bbc383187cf87bfe60be417ac8bce2c42db Mon Sep 17 00:00:00 2001
From: olayiwola-compucorp <olayiwola@compucorp.co.uk>
Date: Fri, 19 Nov 2021 11:51:18 +0100
Subject: [PATCH 2/2] Add docs for the hooks that alter mosaico plugins

---
 docs/api.md | 33 ++++++++++++++++++++++++++++++++-
 1 file changed, 32 insertions(+), 1 deletion(-)

diff --git a/docs/api.md b/docs/api.md
index c026dc6e4a..7fc395e9db 100644
--- a/docs/api.md
+++ b/docs/api.md
@@ -102,4 +102,35 @@ function campaignadv_civicrm_mosaicoScriptUrlsAlter(&$scriptUrls) {
   $url = CRM_Utils_System::url('civicrm/campaignadv/mosaico-js', '', TRUE, NULL, NULL, NULL, NULL);
   $scriptUrls[] = $url;
 }
-```
\ No newline at end of file
+```
+
+## hook_civicrm_mosaicoPlugin(&$plugins)
+
+This hook can be implemented to add custom JS plugins to the Mosaico object during initialization, see [here](https://github.com/voidlabs/mosaico/wiki/Mosaico-Plugins) on how plugins work in Mosaico.
+
+Example usage:
+```
+/**
+ * Implements hook_civicrm_mosaicoPlugin().
+ */
+function example_civicrm_mosaicoPlugin(&$plugins) {
+    $plugins[] = _example_alert_plugin();
+}
+  
+/**
+ * Example plugin to display alert on init and dispose.
+ */  
+function _example_alert_plugin(){
+    $plugin = <<< JS
+        function(vm) {
+            alert("test-plugin");
+            return {
+                    init: function(vm){alert("init");}, 
+                    dispose:  function(vm){alert("dispose");}
+                }  
+        }
+    JS;
+
+    return $plugin;
+}
+```