Override default timezone in TZIndependentFormatter as UTC

The formatter was applying Operating System timezone on top of any offset,
leading to incorrect dates for any values passed to it.

This meant that anything at the start of day at negative GMT timezones, eg. GMT-4
would move back one day, showing incorrect results in the calendar.

Fixed by applying UTC as the timezone for the formatter

Affects issues:
- Possibly fixed #1239

Plan/common/src/main/java/com/djrapitops/plan/delivery/DeliveryUtilities.java

@@ -17,6 +17,7 @@
 package com.djrapitops.plan.delivery;
 
 import com.djrapitops.plan.delivery.formatting.Formatters;
+import com.djrapitops.plan.delivery.rendering.json.graphs.GraphJSONCreator;
 import com.djrapitops.plan.delivery.rendering.json.graphs.Graphs;
 import com.djrapitops.plan.delivery.webserver.Addresses;
 import com.djrapitops.plan.storage.file.PublicHtmlFiles;
@@ -32,18 +33,20 @@ public class DeliveryUtilities {
     private final Lazy<Formatters> formatters;
     private final Lazy<Graphs> graphs;
     private final Lazy<PublicHtmlFiles> publicHtmlFiles;
+    private final Lazy<GraphJSONCreator> graphJSONCreator;
 
     @Inject
     public DeliveryUtilities(
             Lazy<Addresses> addresses,
             Lazy<Formatters> formatters,
             Lazy<Graphs> graphs,
-            Lazy<PublicHtmlFiles> publicHtmlFiles
+            Lazy<PublicHtmlFiles> publicHtmlFiles, Lazy<GraphJSONCreator> graphJSONCreator
     ) {
         this.addresses = addresses;
         this.formatters = formatters;
         this.graphs = graphs;
         this.publicHtmlFiles = publicHtmlFiles;
+        this.graphJSONCreator = graphJSONCreator;
     }
 
     public Addresses getAddresses() {
@@ -62,4 +65,7 @@ public PublicHtmlFiles getPublicHtmlFiles() {
         return publicHtmlFiles.get();
     }
 
+    public GraphJSONCreator getGraphJSONCreator() {
+        return graphJSONCreator.get();
+    }
 }

Plan/common/src/main/java/com/djrapitops/plan/delivery/formatting/time/ISO8601NoClockTZIndependentFormatter.java

@@ -19,6 +19,7 @@
 import com.djrapitops.plan.delivery.formatting.Formatter;
 
 import java.text.SimpleDateFormat;
+import java.util.TimeZone;
 
 /**
  * Formatter for a timestamp in ISO-8601 format without the clock, without applying timezone offset.
@@ -34,6 +35,7 @@ public String apply(Long date) {
 
     private String format(Long date) {
         SimpleDateFormat dateFormat = new SimpleDateFormat("yyyy-MM-dd");
+        dateFormat.setTimeZone(TimeZone.getTimeZone("UTC"));
 
         return dateFormat.format(date);
     }

Plan/common/src/test/java/com/djrapitops/plan/delivery/formatting/time/ISO8601NoClockTZIndependentFormatterTest.java

@@ -0,0 +1,64 @@
+/*
+ *  This file is part of Player Analytics (Plan).
+ *
+ *  Plan is free software: you can redistribute it and/or modify
+ *  it under the terms of the GNU Lesser General Public License v3 as published by
+ *  the Free Software Foundation, either version 3 of the License, or
+ *  (at your option) any later version.
+ *
+ *  Plan is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *  GNU Lesser General Public License for more details.
+ *
+ *  You should have received a copy of the GNU Lesser General Public License
+ *  along with Plan. If not, see <https://www.gnu.org/licenses/>.
+ */
+package com.djrapitops.plan.delivery.formatting.time;
+
+import org.apache.commons.lang3.StringUtils;
+import org.junit.jupiter.api.DisplayName;
+import org.junit.jupiter.api.RepeatedTest;
+import org.junit.jupiter.api.function.Executable;
+import utilities.RandomData;
+
+import java.time.Instant;
+import java.time.ZoneId;
+import java.time.ZonedDateTime;
+import java.util.ArrayList;
+import java.util.List;
+import java.util.concurrent.TimeUnit;
+
+import static org.junit.jupiter.api.Assertions.assertAll;
+import static org.junit.jupiter.api.Assertions.assertEquals;
+
+/**
+ * Tests against https://github.com/plan-player-analytics/Plan/issues/1239 issues.
+ *
+ * @author AuroraLS3
+ */
+class ISO8601NoClockTZIndependentFormatterTest {
+
+    ISO8601NoClockTZIndependentFormatter formatter = new ISO8601NoClockTZIndependentFormatter();
+
+    @RepeatedTest(10)
+    @DisplayName("OS timezone is not applied to Formatter")
+    void osTimeZoneIsNotApplied() {
+        long startOfDay = RandomData.randomTimeAfter(0L);
+        startOfDay = startOfDay - (startOfDay % TimeUnit.DAYS.toMillis(1));
+
+        ZonedDateTime epoch = Instant.EPOCH.atZone(ZoneId.of("UTC"));
+        ZonedDateTime date = epoch.plusSeconds(TimeUnit.MILLISECONDS.toSeconds(startOfDay));
+        String expected = date.getYear() + "-" +
+                StringUtils.leftPad("" + date.getMonthValue(), 2, '0') + "-" +
+                StringUtils.leftPad("" + date.getDayOfMonth(), 2, '0');
+
+        List<Executable> assertions = new ArrayList<>();
+        for (int i = 0; i < 24; i++) {
+            String result = formatter.apply(startOfDay + TimeUnit.HOURS.toMillis(i));
+            final int added = i;
+            assertions.add(() -> assertEquals(expected, result, "Incorrect result when added " + added + " hours"));
+        }
+        assertAll(assertions);
+    }
+}

Plan/common/src/test/java/extension/SeleniumExtension.java

@@ -22,6 +22,8 @@
 import org.openqa.selenium.*;
 import org.openqa.selenium.chrome.ChromeDriver;
 import org.openqa.selenium.chrome.ChromeOptions;
+import org.openqa.selenium.devtools.DevTools;
+import org.openqa.selenium.devtools.v130.emulation.Emulation;
 import org.openqa.selenium.logging.LogType;
 import org.openqa.selenium.logging.LoggingPreferences;
 import org.testcontainers.shaded.org.awaitility.Awaitility;
@@ -100,6 +102,13 @@ private ChromeDriver getChromeWebDriver() {
         return new ChromeDriver(chromeOptions);
     }
 
+    public static void setTimeZone(ChromeDriver chromeDriver, String timeZone) {
+        try (DevTools devTools = chromeDriver.getDevTools()) {
+            devTools.createSession();
+            devTools.send(Emulation.setTimezoneOverride(timeZone));
+        }
+    }
+
     private LoggingPreferences getLoggingPreferences() {
         LoggingPreferences logPrefs = new LoggingPreferences();
         logPrefs.enable(LogType.PERFORMANCE, Level.INFO);

Plan/common/src/test/java/utilities/TestData.java

@@ -94,6 +94,18 @@ private static List<FinishedSession> createSessionsForPlayer(UUID uuid) {
         return sessions;
     }
 
+    public static FinishedSession createSession(UUID uuid, ServerUUID serverUUID, long start) {
+        String[] gms = GMTimes.getGMKeyArray();
+
+        ActiveSession sessionOne = new ActiveSession(uuid, serverUUID, start, serverWorldNames[0], gms[0]);
+
+        UUID otherUUID = uuid.equals(playerUUID) ? player2UUID : playerUUID;
+        sessionOne.addPlayerKill(TestData.getPlayerKill(uuid, otherUUID, serverUUID, "Iron Sword", 1234750L));
+        sessionOne.addPlayerKill(TestData.getPlayerKill(uuid, otherUUID, serverUUID, "Gold Sword", 1234800L));
+
+        return sessionOne.toFinishedSession(start + 500L);
+    }
+
     public static Transaction storeServers() {
         return new Transaction() {
             @Override