/sites/all/modules/contrib/civicrm/CRM/Activity/Form/Task/RemoveFromTag.php

<?php
/*
 +--------------------------------------------------------------------+
 | CiviCRM version 5                                                  |
 +--------------------------------------------------------------------+
 | Copyright CiviCRM LLC (c) 2004-2019                                |
 +--------------------------------------------------------------------+
 | This file is a part of CiviCRM.                                    |
 |                                                                    |
 | CiviCRM is free software; you can copy, modify, and distribute it  |
 | under the terms of the GNU Affero General Public License           |
 | Version 3, 19 November 2007 and the CiviCRM Licensing Exception.   |
 |                                                                    |
 | CiviCRM is distributed in the hope that it will be useful, but     |
 | WITHOUT ANY WARRANTY; without even the implied warranty of         |
 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.               |
 | See the GNU Affero General Public License for more details.        |
 |                                                                    |
 | You should have received a copy of the GNU Affero General Public   |
 | License and the CiviCRM Licensing Exception along                  |
 | with this program; if not, contact CiviCRM LLC                     |
 | at info[AT]civicrm[DOT]org. If you have questions about the        |
 | GNU Affero General Public License or the licensing of CiviCRM,     |
 | see the CiviCRM license FAQ at http://civicrm.org/licensing        |
 +--------------------------------------------------------------------+
 */

/**
 *
 * @package CRM
 * @copyright CiviCRM LLC (c) 2004-2019
 */

/**
 * This class provides the functionality to remove tags of contact(s).
 */
class CRM_Activity_Form_Task_RemoveFromTag extends CRM_Activity_Form_Task {

  /**
   * Name of the tag
   *
   * @var string
   */
  protected $_name;

  /**
   * All the tags in the system
   *
   * @var array
   */
  protected $_tags;

  /**
   * Build the form object.
   */
  public function buildQuickForm() {
    // add select for tag
    $this->_tags = CRM_Core_BAO_Tag::getTags('civicrm_activity');
    foreach ($this->_tags as $tagID => $tagName) {
      $this->_tagElement = &$this->addElement('checkbox', "tag[$tagID]", NULL, $tagName);
    }

    $parentNames = CRM_Core_BAO_Tag::getTagSet('civicrm_activity');
    CRM_Core_Form_Tag::buildQuickForm($this, $parentNames, 'civicrm_activity', NULL, TRUE, FALSE);

    $this->addDefaultButtons(ts('Remove Tags from activities'));
  }

  public function addRules() {
    $this->addFormRule(['CRM_Activity_Form_Task_RemoveFromTag', 'formRule']);
  }

  /**
   * @param CRM_Core_Form $form
   * @param $rule
   *
   * @return array
   */
  public static function formRule($form, $rule) {
    $errors = [];
    if (empty($form['tag']) && empty($form['activity_taglist'])) {
      $errors['_qf_default'] = "Please select atleast one tag.";
    }
    return $errors;
  }

  /**
   * Process the form after the input has been submitted and validated.
   */
  public function postProcess() {
    //get the submitted values in an array
    $params = $this->controller->exportValues($this->_name);

    $activityTags = $tagList = [];

    // check if contact tags exists
    if (!empty($params['tag'])) {
      $activityTags = $params['tag'];
    }

    // check if tags are selected from taglists
    if (!empty($params['activity_taglist'])) {
      foreach ($params['activity_taglist'] as $val) {
        if ($val) {
          if (is_numeric($val)) {
            $tagList[$val] = 1;
          }
          else {
            list($label, $tagID) = explode(',', $val);
            $tagList[$tagID] = 1;
          }
        }
      }
    }
    $tagSets = CRM_Core_BAO_Tag::getTagsUsedFor('civicrm_activity', FALSE, TRUE);

    foreach ($tagSets as $key => $value) {
      $this->_tags[$key] = $value['name'];
    }
    // merge contact and taglist tags
    $allTags = CRM_Utils_Array::crmArrayMerge($activityTags, $tagList);

    $this->_name = [];
    foreach ($allTags as $key => $dnc) {
      $this->_name[] = $this->_tags[$key];

      list($total, $removed, $notRemoved) = CRM_Core_BAO_EntityTag::removeEntitiesFromTag($this->_activityHolderIds,
        $key, 'civicrm_activity', FALSE);

      $status = [
        ts('%count activity un-tagged', [
          'count' => $removed,
          'plural' => '%count activities un-tagged',
        ]),
      ];
      if ($notRemoved) {
        $status[] = ts('1 activity already did not have this tag', [
          'count' => $notRemoved,
          'plural' => '%count activities already did not have this tag',
        ]);
      }
      $status = '<ul><li>' . implode('</li><li>', $status) . '</li></ul>';
      CRM_Core_Session::setStatus($status, ts("Removed Tag <em>%1</em>", [1 => $this->_tags[$key]]), 'success', ['expires' => 0]);
    }
  }

}