From ebc229d525055efe1cbf52e15772bbddf10909a6 Mon Sep 17 00:00:00 2001
From: Pierre-Gilles Leymarie <pierregilles.leymarie@gmail.com>
Date: Mon, 20 Jan 2025 17:17:56 +0100
Subject: [PATCH] Chart: Fix timezone issues

---
 .../device.getDeviceFeaturesAggregates.js     |  5 ++--
 ...device.getDeviceFeaturesAggregates.test.js | 29 +++++++++++++++++++
 2 files changed, 32 insertions(+), 2 deletions(-)

diff --git a/server/lib/device/device.getDeviceFeaturesAggregates.js b/server/lib/device/device.getDeviceFeaturesAggregates.js
index 7a678f7fc1..dc5830bbf7 100644
--- a/server/lib/device/device.getDeviceFeaturesAggregates.js
+++ b/server/lib/device/device.getDeviceFeaturesAggregates.js
@@ -74,8 +74,9 @@ async function getDeviceFeaturesAggregates(selector, intervalInMinutes, maxState
 
   const isBinary = ['binary', 'push'].includes(deviceFeature.type);
 
-  const now = new Date();
-  const intervalDate = new Date(now.getTime() - intervalInMinutes * 60 * 1000);
+  // Get the interval date, and offset in UTC
+  const intervalDate = new Date(Date.now() - intervalInMinutes * 60 * 1000);
+  intervalDate.setMinutes(intervalDate.getMinutes() - intervalDate.getTimezoneOffset());
 
   let values;
 
diff --git a/server/test/lib/device/device.getDeviceFeaturesAggregates.test.js b/server/test/lib/device/device.getDeviceFeaturesAggregates.test.js
index a68fdf9a76..ecff792d0e 100644
--- a/server/test/lib/device/device.getDeviceFeaturesAggregates.test.js
+++ b/server/test/lib/device/device.getDeviceFeaturesAggregates.test.js
@@ -2,6 +2,10 @@ const EventEmitter = require('events');
 const { expect, assert } = require('chai');
 const sinon = require('sinon');
 const { fake } = require('sinon');
+const dayjs = require('dayjs');
+const utc = require('dayjs/plugin/utc');
+const timezone = require('dayjs/plugin/timezone');
+
 const db = require('../../../models');
 const Device = require('../../../lib/device');
 const Job = require('../../../lib/job');
@@ -9,6 +13,10 @@ const Job = require('../../../lib/job');
 const event = new EventEmitter();
 const job = new Job(event);
 
+// Extend Day.js with plugins
+dayjs.extend(utc);
+dayjs.extend(timezone);
+
 const insertStates = async (intervalInMinutes) => {
   const deviceFeatureStateToInsert = [];
   const now = new Date();
@@ -95,6 +103,27 @@ describe('Device.getDeviceFeaturesAggregates non binary feature', function Descr
     expect(device).to.have.property('name');
     expect(deviceFeature).to.have.property('name');
   });
+  it('should test timezone behavior', async () => {
+    // Create current date in Toronto timezone, 30 minutes ago
+    const torontoDate = dayjs()
+      .tz('America/Toronto')
+      .subtract(30, 'minute')
+      .toDate();
+
+    await db.duckDbInsertState('ca91dfdf-55b2-4cf8-a58b-99c0fbf6f5e4', 1, torontoDate);
+    const variable = {
+      getValue: fake.resolves(null),
+    };
+    const stateManager = {
+      get: fake.returns({
+        id: 'ca91dfdf-55b2-4cf8-a58b-99c0fbf6f5e4',
+        name: 'my-feature',
+      }),
+    };
+    const deviceInstance = new Device(event, {}, stateManager, {}, {}, variable, job);
+    const { values } = await deviceInstance.getDeviceFeaturesAggregates('test-device-feature', 60, 100);
+    expect(values).to.have.lengthOf(1);
+  });
   it('should return last day states', async () => {
     await insertStates(48 * 60);
     const variable = {