let btn_submit_modal_export = $('#modalExportFile_submit'),
    has_clicked = false
    ;



    $(btn_submit_modal_export).unbind('click');
    $(btn_submit_modal_export).bind('click', function () {
        if(!has_clicked){
            has_clicked = true;
            let btn_initial_state = $(this).html();
            let data = {
                'fields':[],
                'selection_only': false,
                'selected_ids' : [],
                'separator': $('#export_separator').val(),
                'charset': $('#export_charset').val(),
                'file_format': $('#export_file_format').val(),
                'token' : "{{ csrf_token('app_export') }}",
                'code_export' : $('#export_code_export').val()
            }
            let selected_fields = $('#export_available_fields option');
            $(selected_fields).each(function(){
                let value = $(this).val();
                data.fields.push(value);
            });
            $(btn_submit_modal_export).html(btn_spin);
            $.ajax({
                url: "{{ url('app_export') }}",
                data: data,
                method: 'POST',
                xhr:function(){
                    var xhr = new XMLHttpRequest();
                    xhr.responseType = 'blob'
                    return xhr;
                },
                success: function (response,status, headers) {
                    const regex = /filename=(.*?)$/g
                    let content_disposition = headers.getResponseHeader('Content-Disposition');
                    let search = regex.exec(content_disposition);
                    const url = window.URL.createObjectURL(response);
                    const a = document.createElement('a');
                    a.style.display = 'none';
                    a.href = url;
                    a.download = (search.length >= 1) ? search[1] : 'export.xlsx';
                    document.body.appendChild(a);
                    a.click();
                    window.URL.revokeObjectURL(url);

                    $(btn_submit_modal_export).html(btn_initial_state);
                    $('#modalExportFile').foundation('close');
                    has_clicked = false;
                }
            });
        }

    });