Realtime header component.

components/metrics/RealtimeHeader.js

@@ -0,0 +1,53 @@
+import React from 'react';
+import { FormattedMessage } from 'react-intl';
+import PageHeader from '../layout/PageHeader';
+import DropDown from '../common/DropDown';
+import MetricCard from './MetricCard';
+import styles from './RealtimeHeader.module.css';
+
+export default function RealtimeHeader({ websites, data, websiteId, onSelect }) {
+  const options = [
+    { label: <FormattedMessage id="label.all-websites" defaultMessage="All websites" />, value: 0 },
+  ].concat(websites.map(({ name, website_id }) => ({ label: name, value: website_id })));
+
+  const { pageviews, sessions, events } = data;
+  const countries = sessions.reduce((obj, { country }) => {
+    if (country) {
+      if (!obj[country]) {
+        obj[country] = 1;
+      } else {
+        obj[country] += 1;
+      }
+    }
+    return obj;
+  }, {});
+
+  return (
+    <>
+      <PageHeader>
+        <div>
+          <FormattedMessage id="label.realtime" defaultMessage="Realtime" />
+        </div>
+        <DropDown value={websiteId} options={options} onChange={onSelect} />
+      </PageHeader>
+      <div className={styles.metrics}>
+        <MetricCard
+          label={<FormattedMessage id="metrics.views" defaultMessage="Views" />}
+          value={pageviews.length}
+        />
+        <MetricCard
+          label={<FormattedMessage id="metrics.visitors" defaultMessage="Visitors" />}
+          value={sessions.length}
+        />
+        <MetricCard
+          label={<FormattedMessage id="metrics.events" defaultMessage="Events" />}
+          value={events.length}
+        />
+        <MetricCard
+          label={<FormattedMessage id="metrics.countries" defaultMessage="Countries" />}
+          value={Object.keys(countries).length}
+        />
+      </div>
+    </>
+  );
+}