Hello, I want to add a button in POS Payment widget, just like the default Invoice button. I have managed to add the button there and create a Click event, but i am not being able to print my custom report.

odoo.define('dev_dtr_inv_layout', function (require) {
"use strict";
var screens = require('point_of_sale.screens');
var gui = require('point_of_sale.gui');
var core = require('web.core');
var _t = core._t;
screens.PaymentScreenWidget.include({
       events: {
       'click .js_custom_print': 'orderClickEvent',
   },
   orderClickEvent: function(e){
       alert("Clicked!")
       var self = this;
       var order_name = self.pos.get_order().name
           this._rpc({
               model: 'report.dev_dtr_inv_layout.template_sale_tax_invoice',
               method: 'print_report',
               args: [[]],
           }).then(function (result) {
               self.do_action(result);
           });
           var order = this.pos.get_order();
           order.js_custom_print = !order.js_custom_print;
            if (order.js_custom_print) {
                this.$('.js_custom_print').addClass('highlight');
            } else {
                this.$('.js_custom_print').removeClass('highlight');
            }
   },

});
});
This is my javascript code so far and its throwing errors because of None Type object.
Whats the proper way to print a qweb report from javascript?