[FIX] portal: add loading on sign button

Show a loading spinner and disable sign button on orders
to indicate that the request is processing avoiding users
clicking multiple times and getting an error,
that the order does not require signing

opw-3709064

closes odoo/odoo#157836

Signed-off-by: Valentin Chevalier <vcr@odoo.com>

addons/portal/static/src/signature_form/signature_form.js

@@ -1,6 +1,7 @@
 /** @odoo-module **/
 
 import { Component, onMounted, useRef, useState } from "@odoo/owl";
+import dom from "@web/legacy/js/core/dom";
 import { _t } from "@web/core/l10n/translation";
 import { registry } from "@web/core/registry";
 import { redirect } from "@web/core/utils/urls";
@@ -62,10 +63,16 @@ class SignatureForm extends Component {
      * @returns {Promise}
      */
     async onClickSubmit() {
+        const button = document.querySelector('.o_portal_sign_submit')
+        const icon = button.removeChild(button.firstChild)
+        const restoreBtnLoading = dom.addButtonLoadingEffect(button);
+
         const name = this.signature.name;
         const signature = this.signature.getSignatureImage()[1];
         const data = await this.rpc(this.props.callUrl, { name, signature });
         if (data.force_refresh) {
+            restoreBtnLoading();
+            button.prepend(icon)
             if (data.redirect_url) {
                 redirect(data.redirect_url);
             } else {

addons/portal/static/src/signature_form/signature_form.xml

@@ -22,7 +22,7 @@
                         </div>
                         <div class="text-end my-3">
                             <button type="submit" class="o_portal_sign_submit btn btn-primary" t-on-click.prevent="onClickSubmit" t-att-disabled="signature.isSignatureEmpty ? 'disabled' : ''">
-                                <i class="fa fa-check"/>
+                                <i class="fa fa-check me-1"/>
                                 <t t-esc="sendLabel"/>
                             </button>
                         </div>