openerp.report = function(instance) {
    var wkhtmltopdf_state;

    var trigger_download = function(session, response, c) {
        session.get_file({
            url: '/report/download',
            data: {data: JSON.stringify(response)},
            complete: openerp.web.unblockUI,
            error: c.rpc_error.bind(c)
        });
    }

    instance.web.ActionManager = instance.web.ActionManager.extend({
        ir_actions_report_xml: function(action, options) {
            var self = this;
            instance.web.blockUI();
            action = _.clone(action);
            _t =  instance.web._t;

            // QWeb reports
            if ('report_type' in action && (action.report_type == 'qweb-html' || action.report_type == 'qweb-pdf' || action.report_type == 'controller')) {
                var report_url = '';
                switch (action.report_type) {
                    case 'qweb-html':
                        report_url = '/report/html/' + action.report_name;
                        break;
                    case 'qweb-pdf':
                        report_url = '/report/pdf/' + action.report_name;
                        break;
                    case 'controller':
                        report_url = action.report_file;
                        break;
                    default:
                        report_url = '/report/html/' + action.report_name;
                        break;
                }

                // generic report: no query string
                // particular: query string of action.data.form and context
                if (!('data' in action) || !(action.data)) {
                    if ('active_ids' in action.context) {
                        report_url += "/" + action.context.active_ids.join(',');
                    }
                } else {
                    report_url += "?options=" + encodeURIComponent(JSON.stringify(action.data));
                    report_url += "&context=" + encodeURIComponent(JSON.stringify(action.context));
                }

                var response = new Array();
                response[0] = report_url;
                response[1] = action.report_type;
                var c = openerp.webclient.crashmanager;

                if (action.report_type == 'qweb-html') {
                    window.open(report_url, '_blank', 'height=900,width=1280');
                    instance.web.unblockUI();
                } else if (action.report_type === 'qweb-pdf') {
                    // Trigger the download of the pdf/controller report
                    (wkhtmltopdf_state = wkhtmltopdf_state || openerp.session.rpc('/report/check_wkhtmltopdf')).then(function (presence) {
                        // Fallback on html if wkhtmltopdf is not installed or if OpenERP is started with one worker
                        if (presence === 'install') {
                            self.do_notify(_t('Report'), _t('Unable to find Wkhtmltopdf on this \
system. The report will be shown in html.<br><br><a href="http://wkhtmltopdf.org/" target="_blank">\
wkhtmltopdf.org</a>'), true);
                            report_url = report_url.substring(12)
                            window.open('/report/html/' + report_url, '_blank', 'height=768,width=1024');
                            instance.web.unblockUI();
                            return;
                        } else if (presence === 'workers') {
                            self.do_notify(_t('Report'), _t('You need to start OpenERP with at least two \
workers to print a pdf version of the reports.'), true);
                            report_url = report_url.substring(12)
                            window.open('/report/html/' + report_url, '_blank', 'height=768,width=1024');
                            instance.web.unblockUI();
                            return;
                        } else if (presence === 'upgrade') {
                            self.do_notify(_t('Report'), _t('You should upgrade your version of\
 Wkhtmltopdf to at least 0.12.0 in order to get a correct display of headers and footers as well as\
 support for table-breaking between pages.<br><br><a href="http://wkhtmltopdf.org/" \
 target="_blank">wkhtmltopdf.org</a>'), true);
                        }
                        return trigger_download(self.session, response, c);
                    });
                } else if (action.report_type === 'controller') {
                    return trigger_download(self.session, response, c);
                }                     
            } else {
                return self._super(action, options);
            }
        }
    });
};