[civicrm-core.git] / CRM / Contribute / Form / Task / Invoice.php

<?php
/*
 +--------------------------------------------------------------------+
 | Copyright CiviCRM LLC. All rights reserved.                        |
 |                                                                    |
 | This work is published under the GNU AGPLv3 license with some      |
 | permitted exceptions and without any warranty. For full license    |
 | and copyright information, see https://civicrm.org/licensing       |
 +--------------------------------------------------------------------+
 */

/**
 *
 * @package CRM
 * @copyright CiviCRM LLC https://civicrm.org/licensing
 */

use Civi\Api4\Email;
/**
 * This class provides the functionality to email a group of
 * contacts.
 */
class CRM_Contribute_Form_Task_Invoice extends CRM_Contribute_Form_Task {
  /**
   * Are we operating in "single mode", i.e. updating the task of only
   * one specific contribution?
   *
   * @var bool
   */
  public $_single = FALSE;

  /**
   * Gives all the statues for conribution.
   * @var int
   */
  public $_contributionStatusId;

  /**
   * Gives the HTML template of PDF Invoice.
   * @var string
   */
  public $_messageInvoice;

  /**
   * This variable is used to assign parameters for HTML template of PDF Invoice.
   * @var string
   */
  public $_invoiceTemplate;

  /**
   * Selected output.
   * @var string
   */
  public $_selectedOutput;

  /**
   * Build all the data structures needed to build the form.
   */
  public function preProcess() {
    $id = CRM_Utils_Request::retrieve('id', 'Positive', $this, FALSE);
    if ($id) {
      $this->_contributionIds = [$id];
      $this->_componentClause = " civicrm_contribution.id IN ( $id ) ";
      $this->_single = TRUE;
      $this->assign('totalSelectedContributions', 1);

      // set the redirection after actions
      $contactId = CRM_Utils_Request::retrieve('cid', 'Positive', $this, FALSE);
      $url = CRM_Utils_System::url('civicrm/contact/view/contribution',
        "action=view&reset=1&id={$id}&cid={$contactId}&context=contribution&selectedChild=contribute"
      );

      CRM_Core_Session::singleton()->pushUserContext($url);
    }
    else {
      parent::preProcess();
    }

    // check that all the contribution ids have status Completed, Pending, Refunded, or Partially Paid.
    $this->_contributionStatusId = CRM_Contribute_PseudoConstant::contributionStatus(NULL, 'name');
    $status = ['Completed', 'Pending', 'Refunded', 'Partially paid'];
    $statusId = [];
    foreach ($this->_contributionStatusId as $key => $value) {
      if (in_array($value, $status)) {
        $statusId[] = $key;
      }
    }
    $Id = implode(",", $statusId);
    $query = "SELECT count(*) FROM civicrm_contribution WHERE contribution_status_id NOT IN ($Id) AND {$this->_componentClause}";
    $count = CRM_Core_DAO::singleValueQuery($query);
    if ($count != 0) {
      CRM_Core_Error::statusBounce(ts('Please select only contributions with Completed, Pending, Refunded, or Partially Paid status.'));
    }

    // we have all the contribution ids, so now we get the contact ids
    parent::setContactIDs();
    $this->assign('single', $this->_single);

    $qfKey = CRM_Utils_Request::retrieve('qfKey', 'String', $this);
    $urlParams = 'force=1';
    if (CRM_Utils_Rule::qfKey($qfKey)) {
      $urlParams .= "&qfKey=$qfKey";
    }

    $url = CRM_Utils_System::url('civicrm/contribute/search', $urlParams);
    $breadCrumb = [
      [
        'url' => $url,
        'title' => ts('Search Results'),
      ],
    ];

    CRM_Utils_System::appendBreadCrumb($breadCrumb);

    $this->_selectedOutput = CRM_Utils_Request::retrieve('select', 'String', $this);
    $this->assign('selectedOutput', $this->_selectedOutput);

    CRM_Contact_Form_Task_EmailCommon::preProcessFromAddress($this);
    if ($this->_selectedOutput == 'email') {
      CRM_Utils_System::setTitle(ts('Email Invoice'));
    }
    else {
      CRM_Utils_System::setTitle(ts('Print Contribution Invoice'));
    }
  }

  /**
   * Build the form object.
   */
  public function buildQuickForm() {
    $this->preventAjaxSubmit();
    if (CRM_Core_Permission::check('administer CiviCRM')) {
      $this->assign('isAdmin', 1);
    }

    $this->add('select', 'from_email_address', ts('From'), $this->_fromEmails, TRUE);
    if ($this->_selectedOutput != 'email') {
      $this->addElement('radio', 'output', NULL, ts('Email Invoice'), 'email_invoice');
      $this->addElement('radio', 'output', NULL, ts('PDF Invoice'), 'pdf_invoice');
      $this->addRule('output', ts('Selection required'), 'required');
      $this->addFormRule(['CRM_Contribute_Form_Task_Invoice', 'formRule']);
    }
    else {
      $this->addRule('from_email_address', ts('From Email Address is required'), 'required');
    }

    $attributes = ['class' => 'huge'];
    $this->addEntityRef('cc_id', ts('CC'), [
      'entity' => 'Email',
      'multiple' => TRUE,
    ]);
    $this->add('text', 'subject', ts('Subject'), $attributes + ['placeholder' => ts('Optional')]);
    $this->add('wysiwyg', 'email_comment', ts('If you would like to add personal message to email please add it here. (If sending to more then one receipient the same message will be sent to each contact.)'), [
      'rows' => 2,
      'cols' => 40,
    ]);

    $this->addButtons([
      [
        'type' => 'upload',
        'name' => $this->_selectedOutput == 'email' ? ts('Send Email') : ts('Process Invoice(s)'),
        'isDefault' => TRUE,
      ],
      [
        'type' => 'cancel',
        'name' => ts('Cancel'),
      ],
    ]);
  }

  /**
   * Global validation rules for the form.
   *
   * @param array $values
   *
   * @return array
   *   list of errors to be posted back to the form
   */
  public static function formRule($values) {
    $errors = [];

    if ($values['output'] == 'email_invoice' && empty($values['from_email_address'])) {
      $errors['from_email_address'] = ts("From Email Address is required");
    }

    return $errors;
  }

  /**
   * Process the form after the input has been submitted and validated.
   */
  public function postProcess() {
    $params = $this->controller->exportValues($this->_name);
    self::printPDF($this->_contributionIds, $params, $this->_contactIds);
  }

  /**
   * Process the PDf and email with activity and attachment on click of Print Invoices.
   *
   * @param array $contribIDs
   *   Contribution Id.
   * @param array $params
   *   Associated array of submitted values.
   * @param array $contactIds
   *   Contact Id.
   */
  public static function printPDF($contribIDs, &$params, $contactIds) {
    // get all the details needed to generate a invoice
    $messageInvoice = [];
    $invoiceTemplate = CRM_Core_Smarty::singleton();
    $invoiceElements = CRM_Contribute_Form_Task_PDF::getElements($contribIDs, $params, $contactIds);

    // gives the status id when contribution status is 'Refunded'
    $contributionStatusID = CRM_Contribute_PseudoConstant::contributionStatus(NULL, 'name');
    $refundedStatusId = CRM_Utils_Array::key('Refunded', $contributionStatusID);
    $cancelledStatusId = CRM_Utils_Array::key('Cancelled', $contributionStatusID);
    $pendingStatusId = CRM_Utils_Array::key('Pending', $contributionStatusID);

    foreach ($invoiceElements['details'] as $contribID => $detail) {
      $input = $ids = $objects = [];
      if (in_array($detail['contact'], $invoiceElements['excludeContactIds'])) {
        continue;
      }

      $input['component'] = $detail['component'];

      $ids['contact'] = $detail['contact'];
      $ids['contribution'] = $contribID;
      $ids['contributionRecur'] = NULL;
      $ids['contributionPage'] = NULL;
      $ids['membership'] = $detail['membership'] ?? NULL;
      $ids['participant'] = $detail['participant'] ?? NULL;
      $ids['event'] = $detail['event'] ?? NULL;

      if (!$invoiceElements['baseIPN']->validateData($input, $ids, $objects, FALSE)) {
        CRM_Core_Error::statusBounce('Supplied data was not able to be validated');
      }

      $contribution = &$objects['contribution'];

      $input['amount'] = $contribution->total_amount;
      $input['invoice_id'] = $contribution->invoice_id;
      $input['receive_date'] = $contribution->receive_date;
      $input['contribution_status_id'] = $contribution->contribution_status_id;
      $input['organization_name'] = $contribution->_relatedObjects['contact']->organization_name;

      $objects['contribution']->receive_date = CRM_Utils_Date::isoToMysql($objects['contribution']->receive_date);

      // Fetch the billing address. getValues should prioritize the billing
      // address, otherwise will return the primary address.
      $billingAddress = [];

      $addressDetails = CRM_Core_BAO_Address::getValues([
        'contact_id' => $contribution->contact_id,
        'is_billing' => 1,
      ]);

      if (!empty($addressDetails)) {
        $billingAddress = array_shift($addressDetails);
      }

      if ($contribution->contribution_status_id == $refundedStatusId || $contribution->contribution_status_id == $cancelledStatusId) {
        $creditNoteId = $contribution->creditnote_id;
      }
      if (!$contribution->invoice_number) {
        $contribution->invoice_number = CRM_Contribute_BAO_Contribution::getInvoiceNumber($contribution->id);
      }

      //to obtain due date for PDF invoice
      $contributionReceiveDate = date('F j,Y', strtotime(date($input['receive_date'])));
      $invoiceDate = date("F j, Y");
      $dueDateSetting = Civi::settings()->get('invoice_due_date');
      $dueDatePeriodSetting = Civi::settings()->get('invoice_due_date_period');
      $dueDate = date('F j, Y', strtotime($contributionReceiveDate . "+" . $dueDateSetting . "" . $dueDatePeriodSetting));

      $amountPaid = CRM_Core_BAO_FinancialTrxn::getTotalPayments($contribID, TRUE);
      $amountDue = ($input['amount'] - $amountPaid);

      // retrieving the subtotal and sum of same tax_rate
      $dataArray = [];
      $subTotal = 0;
      $lineItem = CRM_Price_BAO_LineItem::getLineItemsByContributionID($contribID);
      foreach ($lineItem as $taxRate) {
        if (isset($dataArray[(string) $taxRate['tax_rate']])) {
          $dataArray[(string) $taxRate['tax_rate']] = $dataArray[(string) $taxRate['tax_rate']] + CRM_Utils_Array::value('tax_amount', $taxRate);
        }
        else {
          $dataArray[(string) $taxRate['tax_rate']] = $taxRate['tax_amount'] ?? NULL;
        }
        $subTotal += CRM_Utils_Array::value('subTotal', $taxRate);
      }

      // to email the invoice
      $mailDetails = [];
      $values = [];
      if ($contribution->_component == 'event') {
        $daoName = 'CRM_Event_DAO_Event';
        $pageId = $contribution->_relatedObjects['event']->id;
        $mailElements = [
          'title',
          'confirm_from_name',
          'confirm_from_email',
        ];
        CRM_Core_DAO::commonRetrieveAll($daoName, 'id', $pageId, $mailDetails, $mailElements);
        $values['title'] = $mailDetails[$contribution->_relatedObjects['event']->id]['title'] ?? NULL;
        $values['confirm_from_name'] = $mailDetails[$contribution->_relatedObjects['event']->id]['confirm_from_name'] ?? NULL;
        $values['confirm_from_email'] = $mailDetails[$contribution->_relatedObjects['event']->id]['confirm_from_email'] ?? NULL;

        $title = $mailDetails[$contribution->_relatedObjects['event']->id]['title'] ?? NULL;
      }
      elseif ($contribution->_component == 'contribute') {
        $daoName = 'CRM_Contribute_DAO_ContributionPage';
        $pageId = $contribution->contribution_page_id;
        $mailElements = [
          'title',
          'receipt_from_name',
          'receipt_from_email',
          'cc_receipt',
          'bcc_receipt',
        ];
        CRM_Core_DAO::commonRetrieveAll($daoName, 'id', $pageId, $mailDetails, $mailElements);

        $values['title'] = CRM_Utils_Array::value('title', CRM_Utils_Array::value($contribution->contribution_page_id, $mailDetails));
        $values['receipt_from_name'] = CRM_Utils_Array::value('receipt_from_name', CRM_Utils_Array::value($contribution->contribution_page_id, $mailDetails));
        $values['receipt_from_email'] = CRM_Utils_Array::value('receipt_from_email', CRM_Utils_Array::value($contribution->contribution_page_id, $mailDetails));
        $values['cc_receipt'] = CRM_Utils_Array::value('cc_receipt', CRM_Utils_Array::value($contribution->contribution_page_id, $mailDetails));
        $values['bcc_receipt'] = CRM_Utils_Array::value('bcc_receipt', CRM_Utils_Array::value($contribution->contribution_page_id, $mailDetails));

        $title = CRM_Utils_Array::value('title', CRM_Utils_Array::value($contribution->contribution_page_id, $mailDetails));
      }
      $source = $contribution->source;

      $config = CRM_Core_Config::singleton();
      if (!isset($params['forPage'])) {
        $config->doNotAttachPDFReceipt = 1;
      }

      // get organization address
      $domain = CRM_Core_BAO_Domain::getDomain();
      $locParams = ['contact_id' => $domain->contact_id];
      $locationDefaults = CRM_Core_BAO_Location::getValues($locParams);
      if (isset($locationDefaults['address'][1]['state_province_id'])) {
        $stateProvinceAbbreviationDomain = CRM_Core_PseudoConstant::stateProvinceAbbreviation($locationDefaults['address'][1]['state_province_id']);
      }
      else {
        $stateProvinceAbbreviationDomain = '';
      }
      if (isset($locationDefaults['address'][1]['country_id'])) {
        $countryDomain = CRM_Core_PseudoConstant::country($locationDefaults['address'][1]['country_id']);
      }
      else {
        $countryDomain = '';
      }

      $invoiceNotes = Civi::settings()->get('invoice_notes') ?? NULL;

      // parameters to be assign for template
      $tplParams = [
        'title' => $title,
        'component' => $input['component'],
        'id' => $contribution->id,
        'source' => $source,
        'invoice_number' => $contribution->invoice_number,
        'invoice_id' => $contribution->invoice_id,
        'resourceBase' => $config->userFrameworkResourceURL,
        'defaultCurrency' => $config->defaultCurrency,
        'amount' => $contribution->total_amount,
        'amountDue' => $amountDue,
        'amountPaid' => $amountPaid,
        'invoice_date' => $invoiceDate,
        'dueDate' => $dueDate,
        'notes' => $invoiceNotes,
        'display_name' => $contribution->_relatedObjects['contact']->display_name,
        'lineItem' => $lineItem,
        'dataArray' => $dataArray,
        'refundedStatusId' => $refundedStatusId,
        'pendingStatusId' => $pendingStatusId,
        'cancelledStatusId' => $cancelledStatusId,
        'contribution_status_id' => $contribution->contribution_status_id,
        'contributionStatusName' => CRM_Core_PseudoConstant::getName('CRM_Contribute_BAO_Contribution', 'contribution_status_id', $contribution->contribution_status_id),
        'subTotal' => $subTotal,
        'street_address' => $billingAddress['street_address'] ?? NULL,
        'supplemental_address_1' => $billingAddress['supplemental_address_1'] ?? NULL,
        'supplemental_address_2' => $billingAddress['supplemental_address_2'] ?? NULL,
        'supplemental_address_3' => $billingAddress['supplemental_address_3'] ?? NULL,
        'city' => $billingAddress['city'] ?? NULL,
        'postal_code' => $billingAddress['postal_code'] ?? NULL,
        'state_province' => $billingAddress['state_province'] ?? NULL,
        'state_province_abbreviation' => $billingAddress['state_province_abbreviation'] ?? NULL,
        // Kept for backwards compatibility
        'stateProvinceAbbreviation' => $billingAddress['state_province_abbreviation'] ?? NULL,
        'country' => $billingAddress['country'] ?? NULL,
        'is_pay_later' => $contribution->is_pay_later,
        'organization_name' => $contribution->_relatedObjects['contact']->organization_name,
        'domain_organization' => $domain->name,
        'domain_street_address' => CRM_Utils_Array::value('street_address', CRM_Utils_Array::value('1', $locationDefaults['address'])),
        'domain_supplemental_address_1' => CRM_Utils_Array::value('supplemental_address_1', CRM_Utils_Array::value('1', $locationDefaults['address'])),
        'domain_supplemental_address_2' => CRM_Utils_Array::value('supplemental_address_2', CRM_Utils_Array::value('1', $locationDefaults['address'])),
        'domain_supplemental_address_3' => CRM_Utils_Array::value('supplemental_address_3', CRM_Utils_Array::value('1', $locationDefaults['address'])),
        'domain_city' => CRM_Utils_Array::value('city', CRM_Utils_Array::value('1', $locationDefaults['address'])),
        'domain_postal_code' => CRM_Utils_Array::value('postal_code', CRM_Utils_Array::value('1', $locationDefaults['address'])),
        'domain_state' => $stateProvinceAbbreviationDomain,
        'domain_country' => $countryDomain,
        'domain_email' => CRM_Utils_Array::value('email', CRM_Utils_Array::value('1', $locationDefaults['email'])),
        'domain_phone' => CRM_Utils_Array::value('phone', CRM_Utils_Array::value('1', $locationDefaults['phone'])),
      ];

      if (isset($creditNoteId)) {
        $tplParams['creditnote_id'] = $creditNoteId;
      }

      $pdfFileName = $contribution->invoice_number . ".pdf";
      $sendTemplateParams = [
        'groupName' => 'msg_tpl_workflow_contribution',
        'valueName' => 'contribution_invoice_receipt',
        'contactId' => $contribution->contact_id,
        'tplParams' => $tplParams,
        'PDFFilename' => $pdfFileName,
      ];

      // from email address
      $fromEmailAddress = $params['from_email_address'] ?? NULL;
      if (!empty($params['cc_id'])) {
        // get contacts and their emails from email id
        $emailIDs = $params['cc_id'] ? explode(',', $params['cc_id']) : [];
        $emails = Email::get()
          ->addWhere('id', 'IN', $emailIDs)
          ->setCheckPermissions(FALSE)
          ->setSelect(['contact_id', 'email', 'contact.sort_name', 'contact.display_name'])->execute();
        $emailStrings = $contactUrlStrings = [];
        foreach ($emails as $email) {
          $emailStrings[] = '"' . $email['contact.sort_name'] . '" <' . $email['email'] . '>';
          // generate the contact url to put in Activity
          $contactURL = CRM_Utils_System::url('civicrm/contact/view', ['reset' => 1, 'force' => 1, 'cid' => $email['contact_id']], TRUE);
          $contactUrlStrings[] = "<a href='{$contactURL}'>" . $email['contact.display_name'] . '</a>';
        }
        $cc_emails = implode(',', $emailStrings);
        $values['cc_receipt'] = $cc_emails;
        $ccContactsDetails = implode(',', $contactUrlStrings);
        // add CC emails as activity details
        $params['activity_details'] = "\ncc : " . $ccContactsDetails;

        // unset bcc to avoid unknown email come from online page configuration.
        unset($values['bcc_receipt']);
      }

      // get subject from UI
      if (!empty($params['subject'])) {
        $sendTemplateParams['subject'] = $values['subject'] = $params['subject'];
      }

      // condition to check for download PDF Invoice or email Invoice
      if ($invoiceElements['createPdf']) {
        list($sent, $subject, $message, $html) = CRM_Core_BAO_MessageTemplate::sendTemplate($sendTemplateParams);
        if (isset($params['forPage'])) {
          return $html;
        }
        else {
          $mail = [
            'subject' => $subject,
            'body' => $message,
            'html' => $html,
          ];
          if ($mail['html']) {
            $messageInvoice[] = $mail['html'];
          }
          else {
            $messageInvoice[] = nl2br($mail['body']);
          }
        }
      }
      elseif ($contribution->_component == 'contribute') {
        $email = CRM_Contact_BAO_Contact::getPrimaryEmail($contribution->contact_id);

        $sendTemplateParams['tplParams'] = array_merge($tplParams, ['email_comment' => $invoiceElements['params']['email_comment']]);
        $sendTemplateParams['from'] = $fromEmailAddress;
        $sendTemplateParams['toEmail'] = $email;
        $sendTemplateParams['cc'] = $values['cc_receipt'] ?? NULL;
        $sendTemplateParams['bcc'] = $values['bcc_receipt'] ?? NULL;

        list($sent, $subject, $message, $html) = CRM_Core_BAO_MessageTemplate::sendTemplate($sendTemplateParams);
        // functions call for adding activity with attachment
        // make sure page layout is same for email and download invoices.
        $fileName = self::putFile($html, $pdfFileName, [
          'margin_top' => 10,
          'margin_left' => 65,
          'metric' => 'px',
        ]);
        self::addActivities($subject, $contribution->contact_id, $fileName, $params, $contribution->id);
      }
      elseif ($contribution->_component == 'event') {
        $email = CRM_Contact_BAO_Contact::getPrimaryEmail($contribution->contact_id);

        $sendTemplateParams['tplParams'] = array_merge($tplParams, ['email_comment' => $invoiceElements['params']['email_comment']]);
        $sendTemplateParams['from'] = $fromEmailAddress;
        $sendTemplateParams['toEmail'] = $email;
        $sendTemplateParams['cc'] = $values['cc_confirm'] ?? NULL;
        $sendTemplateParams['bcc'] = $values['bcc_confirm'] ?? NULL;

        list($sent, $subject, $message, $html) = CRM_Core_BAO_MessageTemplate::sendTemplate($sendTemplateParams);
        // functions call for adding activity with attachment
        $fileName = self::putFile($html, $pdfFileName);
        self::addActivities($subject, $contribution->contact_id, $fileName, $params, $contribution->id);
      }
      $invoiceTemplate->clearTemplateVars();
    }

    if ($invoiceElements['createPdf']) {
      if (isset($params['forPage'])) {
        return $html;
      }
      else {
        CRM_Utils_PDF_Utils::html2pdf($messageInvoice, $pdfFileName, FALSE, [
          'margin_top' => 10,
          'margin_left' => 65,
          'metric' => 'px',
        ]);
        // functions call for adding activity with attachment
        $fileName = self::putFile($html, $pdfFileName, [
          'margin_top' => 10,
          'margin_left' => 65,
          'metric' => 'px',
        ]);
        self::addActivities($subject, $contactIds, $fileName, $params);

        CRM_Utils_System::civiExit();
      }
    }
    else {
      if ($invoiceElements['suppressedEmails']) {
        $status = ts('Email was NOT sent to %1 contacts (no email address on file, or communication preferences specify DO NOT EMAIL, or contact is deceased).', [1 => $invoiceElements['suppressedEmails']]);
        $msgTitle = ts('Email Error');
        $msgType = 'error';
      }
      else {
        $status = ts('Your mail has been sent.');
        $msgTitle = ts('Sent');
        $msgType = 'success';
      }
      CRM_Core_Session::setStatus($status, $msgTitle, $msgType);
    }
  }

  /**
   * Add activity for Email Invoice and the PDF Invoice.
   *
   * @param string $subject
   *   Activity subject.
   * @param array $contactIds
   *   Contact Id.
   * @param string $fileName
   *   Gives the location with name of the file.
   * @param array $params
   *   For invoices.
   * @param int $contributionId
   *   Contribution Id.
   *
   */
  public static function addActivities($subject, $contactIds, $fileName, $params, $contributionId = NULL) {
    $session = CRM_Core_Session::singleton();
    $userID = $session->get('userID');
    $config = CRM_Core_Config::singleton();
    $config->doNotAttachPDFReceipt = 1;

    if (!empty($params['output']) && $params['output'] == 'pdf_invoice') {
      $activityType = 'Downloaded Invoice';
    }
    else {
      $activityType = 'Emailed Invoice';
    }

    $activityParams = [
      'subject' => $subject,
      'source_contact_id' => $userID,
      'target_contact_id' => $contactIds,
      'activity_type_id' => $activityType,
      'activity_date_time' => date('YmdHis'),
      'details' => $params['activity_details'] ?? NULL,
      'attachFile_1' => [
        'uri' => $fileName,
        'type' => 'application/pdf',
        'location' => $fileName,
        'upload_date' => date('YmdHis'),
      ],
    ];
    if ($contributionId) {
      $activityParams['source_record_id'] = $contributionId;
    }
    civicrm_api3('Activity', 'create', $activityParams);
  }

  /**
   * Create the Invoice file in upload folder for attachment.
   *
   * @param string $html
   *   Content for pdf in html format.
   *
   * @param string $name
   * @param array $format
   *
   * @return string
   *   Name of file which is in pdf format
   */
  public static function putFile($html, $name = 'Invoice.pdf', $format = NULL) {
    return CRM_Utils_Mail::appendPDF($name, $html, $format)['fullPath'] ?? '';
  }

  /**
   * Callback to perform action on Print Invoice button.
   */
  public static function getPrintPDF() {
    $contributionId = CRM_Utils_Request::retrieve('id', 'Positive', CRM_Core_DAO::$_nullObject, FALSE);
    $contributionIDs = [$contributionId];
    $contactId = CRM_Utils_Request::retrieve('cid', 'Positive', CRM_Core_DAO::$_nullObject, FALSE);
    $params = ['output' => 'pdf_invoice'];
    CRM_Contribute_Form_Task_Invoice::printPDF($contributionIDs, $params, $contactId);
  }

}