From efdbd1c63212c943df443048ea47a909f2c83cae Mon Sep 17 00:00:00 2001
From: Mike Cao <mike@mikecao.com>
Date: Wed, 29 Jul 2020 21:40:26 -0700
Subject: [PATCH] Updated summary query. Added visit time.

---
 components/WebsiteSummary.js      |  8 +++++-
 lib/db.js                         | 37 +++++++++++-----------------
 lib/format.js                     | 41 +++++++++++++++++++++++++++++++
 pages/api/website/[id]/summary.js |  7 +++++-
 4 files changed, 69 insertions(+), 24 deletions(-)
 create mode 100644 lib/format.js

diff --git a/components/WebsiteSummary.js b/components/WebsiteSummary.js
index afa1aeeb..cee9f044 100644
--- a/components/WebsiteSummary.js
+++ b/components/WebsiteSummary.js
@@ -1,11 +1,12 @@
 import React, { useState, useEffect } from 'react';
 import MetricCard from './MetricCard';
 import { get } from '../lib/web';
+import { formatShortTime } from 'lib/format';
 import styles from './WebsiteSummary.module.css';
 
 export default function WebsiteSummary({ websiteId, startDate, endDate }) {
   const [data, setData] = useState({});
-  const { pageviews, uniques, bounces } = data;
+  const { pageviews, uniques, bounces, totaltime } = data;
 
   async function loadData() {
     setData(
@@ -29,6 +30,11 @@ export default function WebsiteSummary({ websiteId, startDate, endDate }) {
         value={uniques ? (bounces / uniques) * 100 : 0}
         format={n => Number(n).toFixed(0) + '%'}
       />
+      <MetricCard
+        label="Average visit time"
+        value={totaltime && pageviews ? totaltime / (pageviews - bounces) : 0}
+        format={n => formatShortTime(n, ['m', 's'], ' ')}
+      />
     </div>
   );
 }
diff --git a/lib/db.js b/lib/db.js
index b829c101..102f100e 100644
--- a/lib/db.js
+++ b/lib/db.js
@@ -184,28 +184,21 @@ export async function getSummary(website_id, start_at, end_at) {
   return runQuery(
     prisma.queryRaw(
       `
-      select
-         (select count(*)
-            from pageview
-            where website_id=${website_id}
-            and created_at between '${start_at}' and '${end_at}'
-          ) as "pageviews",
-         (select
-            count(distinct session_id)
-            from pageview
-            where website_id=${website_id}
-            and created_at between '${start_at}' and '${end_at}'
-         ) as "uniques",
-         (select sum(t.c) from
-           (select count(*) c
-              from pageview
-              where website_id=${website_id}
-              and created_at between '${start_at}' and '${end_at}'
-              group by session_id
-              having count(*) = 1
-          ) t
-         ) as "bounces"
-      `,
+      select sum(t.c) as "pageviews",
+        count(distinct t.session_id) as "uniques",
+        sum(case when t.c = 1 then t.c else 0 end) as "bounces",
+        sum(t.time) as "totaltime"
+      from (
+         select session_id,
+           date_trunc('hour', created_at),
+           count(*) c,
+           floor(extract(epoch from max(created_at) - min(created_at))) as "time"
+         from pageview
+         where website_id=${website_id}
+         and created_at between '${start_at}' and '${end_at}'
+         group by 1, 2
+     ) t;
+     `,
     ),
   );
 }
diff --git a/lib/format.js b/lib/format.js
new file mode 100644
index 00000000..c9480f31
--- /dev/null
+++ b/lib/format.js
@@ -0,0 +1,41 @@
+export function parseTime(val) {
+  const days = ~~(val / 86400);
+  const hours = ~~(val / 3600) - days * 24;
+  const minutes = ~~(val / 60) - days * 1440 - hours * 60;
+  const seconds = ~~val - days * 86400 - hours * 3600 - minutes * 60;
+  const ms = (val - ~~val) * 1000;
+
+  return {
+    days,
+    hours,
+    minutes,
+    seconds,
+    ms,
+  };
+}
+
+export function formatTime(val) {
+  const { hour, minutes, seconds } = parseTime(val);
+  const h = hour > 0 ? `${hour}:` : '';
+  const m = hour > 0 ? minutes.toString().padStart(2, '0') : minutes;
+  const s = seconds.toString().padStart(2, '0');
+
+  return `${h}${m}:${s}`;
+}
+
+export function formatShortTime(val, formats = ['m', 's'], space = '') {
+  if (val === 0) {
+    return `0${formats[formats.length - 1]}`;
+  }
+
+  const { days, hours, minutes, seconds, ms } = parseTime(val);
+  let t = '';
+
+  if (days > 0 && formats.indexOf('d') !== -1) t += `${days}d${space}`;
+  if (hours > 0 && formats.indexOf('h') !== -1) t += `${hours}h${space}`;
+  if (minutes > 0 && formats.indexOf('m') !== -1) t += `${minutes}m${space}`;
+  if (seconds > 0 && formats.indexOf('s') !== -1) t += `${seconds}s${space}`;
+  if (ms > 0 && formats.indexOf('ms') !== -1) t += `${ms}ms`;
+
+  return t;
+}
diff --git a/pages/api/website/[id]/summary.js b/pages/api/website/[id]/summary.js
index a440b793..a1882ad5 100644
--- a/pages/api/website/[id]/summary.js
+++ b/pages/api/website/[id]/summary.js
@@ -13,5 +13,10 @@ export default async (req, res) => {
     format(new Date(+end_at), 'yyyy-MM-dd hh:mm:ss'),
   );
 
-  return res.status(200).json(summary[0]);
+  const stats = Object.keys(summary[0]).reduce((obj, key) => {
+    obj[key] = +summary[0][key];
+    return obj;
+  }, {});
+
+  return res.status(200).json(stats);
 };