From e07ea0398f56bbff8dec97bbf70aa51e17b17870 Mon Sep 17 00:00:00 2001
From: Guillaume Thomas <guillaume.thomas@optimdata.eu>
Date: Tue, 1 Jun 2021 16:02:23 +0200
Subject: [PATCH] Fix handling of InUse timezone for date_histogram (#44)

Co-authored-by: Guillaume Thomas <guillaume.thomas@inuse.eu>
---
 .../agg_types/buckets/date_histogram.js       | 30 +++++++++++++++++--
 src/ui/public/vis/lib/timezone.js             | 19 +++++++++++-
 2 files changed, 45 insertions(+), 4 deletions(-)

diff --git a/src/ui/public/agg_types/buckets/date_histogram.js b/src/ui/public/agg_types/buckets/date_histogram.js
index 16e336514d..0c206f9640 100644
--- a/src/ui/public/agg_types/buckets/date_histogram.js
+++ b/src/ui/public/agg_types/buckets/date_histogram.js
@@ -32,6 +32,22 @@ import { timefilter } from '../../timefilter';
 import dropPartialTemplate from '../controls/drop_partials.html';
 import { i18n } from '@kbn/i18n';
 
+function getCookie(cname) {
+  const name = cname + '=';
+  const decodedCookie = decodeURIComponent(document.cookie);
+  const ca = decodedCookie.split(';');
+  for(let i = 0; i < ca.length; i++) {
+    let c = ca[i];
+    while (c.charAt(0) === ' ') {
+      c = c.substring(1);
+    }
+    if (c.indexOf(name) === 0) {
+      return c.substring(name.length, c.length);
+    }
+  }
+  return '';
+}
+
 const config = chrome.getUiSettingsClient();
 const detectedTimezone = tzDetect.determine().name();
 const tzOffset = moment().format('Z');
@@ -52,6 +68,7 @@ function setBounds(agg, force) {
 }
 
 
+
 export const dateHistogramBucketAgg = new BucketAggType({
   name: 'date_histogram',
   title: i18n.translate('common.ui.aggTypes.buckets.dateHistogramTitle', {
@@ -157,9 +174,16 @@ export const dateHistogramBucketAgg = new BucketAggType({
     },
     {
       name: 'time_zone',
-      default: () => {
-        const isDefaultTimezone = config.isDefault('dateFormat:tz');
-        return isDefaultTimezone ? detectedTimezone || tzOffset : config.get('dateFormat:tz');
+      write: (agg, output) => {
+        if (config.isDefault('dateFormat:tz')) {
+          output.params.time_zone = getCookie('timezone');
+        }
+        else if (config.get('dateFormat:tz') === 'Browser') {
+          output.params.time_zone = detectedTimezone || tzOffset;
+        }
+        else {
+          output.params.time_zone = config.get('dateFormat:tz');
+        }
       },
     },
     {
diff --git a/src/ui/public/vis/lib/timezone.js b/src/ui/public/vis/lib/timezone.js
index 473be70aa7..678ad4cae0 100644
--- a/src/ui/public/vis/lib/timezone.js
+++ b/src/ui/public/vis/lib/timezone.js
@@ -20,10 +20,27 @@
 const tzDetect = require('jstimezonedetect').jstz;
 import moment from 'moment';
 
+function getCookie(cname) {
+  const name = cname + '=';
+  const decodedCookie = decodeURIComponent(document.cookie);
+  const ca = decodedCookie.split(';');
+  for(let i = 0; i < ca.length; i++) {
+    let c = ca[i];
+    while (c.charAt(0) === ' ') {
+      c = c.substring(1);
+    }
+    if (c.indexOf(name) === 0) {
+      return c.substring(name.length, c.length);
+    }
+  }
+  return '';
+}
+
 export function timezoneProvider(config) {
   return function () {
-
     if (config.isDefault('dateFormat:tz')) {
+      return getCookie('timezone');
+    } else if (config.get('dateFormat:tz') === 'Browser') {
       const detectedTimezone = tzDetect.determine().name();
       if (detectedTimezone) return detectedTimezone;
       else return moment().format('Z');