From e91f4dcd795a1dc2abed083bb816154d4b1366cb Mon Sep 17 00:00:00 2001
From: Matthew Olsson <matthewcolsson@gmail.com>
Date: Sat, 9 Mar 2024 14:58:10 -0700
Subject: [PATCH] LibWeb: Use Performance for animation time instead of
 MonotonicTime

Performance handles the document origin time correctly, and prevents
these times from being unusually large. Also initialize the
DocumentTimeline time in the constructor, since these can be created
from JS.
---
 Userland/Libraries/LibWeb/Animations/Animation.cpp        | 5 +++--
 Userland/Libraries/LibWeb/Animations/DocumentTimeline.cpp | 5 ++++-
 Userland/Libraries/LibWeb/DOM/Document.cpp                | 7 +++----
 3 files changed, 10 insertions(+), 7 deletions(-)

diff --git a/Userland/Libraries/LibWeb/Animations/Animation.cpp b/Userland/Libraries/LibWeb/Animations/Animation.cpp
index b62e47a1d0..cb6a503fcc 100644
--- a/Userland/Libraries/LibWeb/Animations/Animation.cpp
+++ b/Userland/Libraries/LibWeb/Animations/Animation.cpp
@@ -14,6 +14,7 @@
 #include <LibWeb/DOM/Document.h>
 #include <LibWeb/HTML/Scripting/TemporaryExecutionContext.h>
 #include <LibWeb/HTML/Window.h>
+#include <LibWeb/HighResolutionTime/Performance.h>
 #include <LibWeb/WebIDL/ExceptionOr.h>
 #include <LibWeb/WebIDL/Promise.h>
 
@@ -661,7 +662,7 @@ WebIDL::ExceptionOr<void> Animation::play_an_animation(AutoRewind auto_rewind)
     //     If a user agent determines that animation is immediately ready, it may schedule the above task as a microtask
     //     such that it runs at the next microtask checkpoint, but it must not perform the task synchronously.
     m_pending_play_task = TaskState::Scheduled;
-    m_saved_play_time = MonotonicTime::now().milliseconds();
+    m_saved_play_time = global_object().performance()->now();
 
     // 13. Run the procedure to update an animation’s finished state for animation with the did seek flag set to false,
     //     and the synchronously notify flag set to false.
@@ -745,7 +746,7 @@ WebIDL::ExceptionOr<void> Animation::pause()
     //
     // Note: This is run_pending_pause_task()
     m_pending_pause_task = TaskState::Scheduled;
-    m_saved_pause_time = MonotonicTime::now().milliseconds();
+    m_saved_pause_time = global_object().performance()->now();
 
     // 11. Run the procedure to update an animation’s finished state for animation with the did seek flag set to false,
     //     and the synchronously notify flag set to false.
diff --git a/Userland/Libraries/LibWeb/Animations/DocumentTimeline.cpp b/Userland/Libraries/LibWeb/Animations/DocumentTimeline.cpp
index a9f43730bf..6982cc3512 100644
--- a/Userland/Libraries/LibWeb/Animations/DocumentTimeline.cpp
+++ b/Userland/Libraries/LibWeb/Animations/DocumentTimeline.cpp
@@ -9,6 +9,7 @@
 #include <LibWeb/Animations/DocumentTimeline.h>
 #include <LibWeb/DOM/Document.h>
 #include <LibWeb/HTML/Window.h>
+#include <LibWeb/HighResolutionTime/Performance.h>
 #include <LibWeb/WebIDL/ExceptionOr.h>
 
 namespace Web::Animations {
@@ -17,7 +18,9 @@ JS_DEFINE_ALLOCATOR(DocumentTimeline);
 
 JS::NonnullGCPtr<DocumentTimeline> DocumentTimeline::create(JS::Realm& realm, DOM::Document& document, HighResolutionTime::DOMHighResTimeStamp origin_time)
 {
-    return realm.heap().allocate<DocumentTimeline>(realm, realm, document, origin_time);
+    auto timeline = realm.heap().allocate<DocumentTimeline>(realm, realm, document, origin_time);
+    timeline->set_current_time(document.window().performance()->now());
+    return timeline;
 }
 
 // https://www.w3.org/TR/web-animations-1/#dom-documenttimeline-documenttimeline
diff --git a/Userland/Libraries/LibWeb/DOM/Document.cpp b/Userland/Libraries/LibWeb/DOM/Document.cpp
index 34ff642720..2aad5211d6 100644
--- a/Userland/Libraries/LibWeb/DOM/Document.cpp
+++ b/Userland/Libraries/LibWeb/DOM/Document.cpp
@@ -92,6 +92,7 @@
 #include <LibWeb/HTML/TraversableNavigable.h>
 #include <LibWeb/HTML/Window.h>
 #include <LibWeb/HTML/WindowProxy.h>
+#include <LibWeb/HighResolutionTime/Performance.h>
 #include <LibWeb/HighResolutionTime/TimeOrigin.h>
 #include <LibWeb/Infra/CharacterTypes.h>
 #include <LibWeb/Infra/Strings.h>
@@ -3847,10 +3848,8 @@ JS::NonnullGCPtr<Animations::DocumentTimeline> Document::timeline()
 {
     // The DocumentTimeline object representing the default document timeline. The default document timeline has an
     // origin time of zero.
-    if (!m_default_timeline) {
+    if (!m_default_timeline)
         m_default_timeline = Animations::DocumentTimeline::create(realm(), *this, 0.0);
-        m_default_timeline->set_current_time(MonotonicTime::now().milliseconds());
-    }
     return *m_default_timeline;
 }
 
@@ -4037,7 +4036,7 @@ void Document::ensure_animation_timer()
                 return;
             }
 
-            update_animations_and_send_events(MonotonicTime::now().milliseconds());
+            update_animations_and_send_events(window().performance()->now());
 
             for (auto& timeline : m_associated_animation_timelines) {
                 for (auto& animation : timeline->associated_animations())