{% load lock_tokens_tags %}
{% lock_tokens_api_client %}
<script type="text/javascript">
    var keep_lock_on_unload = false;
    var valid_token = false;
    document.addEventListener("lock_tokens.clientready", function () {
        LockTokens.register_existing_lock_token("{{ app_label }}", "{{ model_name }}", "{{ object_id }}", "{{ token }}",
            function (token) {
                if (token) {
                    valid_token = true;
                } else {
                    // This situation should only happen when the user refreshed the page
                    // or got to previous page then came back
                    confirmed = window.confirm("There was a problem during object locking. You should refresh the page to lock the object properly.\nDo you want to refresh ?")
                    if (confirmed) {
                        location.reload();
                    }
                }
            });

        function set_keep_lock_on_unload(e) {
            e = e || window.event;
            keep_lock_on_unload = true;
        }

        var submit_buttons = document.querySelectorAll("input[type=submit]");
        for (var i=0; i<submit_buttons.length; ++i) {
            var button = submit_buttons[i];
            button.onclick = set_keep_lock_on_unload;
        }

        var delete_links = document.getElementsByClassName('deletelink');
        for (var i=0; i<delete_links.length; ++i) {
            var link = delete_links[i];
            link.onclick = set_keep_lock_on_unload;
        }
    });

    window.onunload = function () {
      /* Unlock model before leaving page without saving */
        if (!keep_lock_on_unload && valid_token) {
            LockTokens.api_client_.async_call_ = false;
            LockTokens.unlock("{{ app_label }}", "{{ model_name }}", "{{ object_id }}");
          }
    };
</script>