From 6fa4382bc6b45cd41b67ab3c9fbe8ad4b02fe4fe Mon Sep 17 00:00:00 2001
From: Phaneron <superp00t@tutanota.com>
Date: Thu, 2 Oct 2025 16:45:17 -0400
Subject: [PATCH] feat(event): implement synchronous key and mouse state
 tracking (#88)

Co-authored-by: fallenoak <git@fallenoak.me>
---
 src/event/Event.cpp | 26 +++++++++++-
 src/event/Queue.cpp | 98 ++++++++++++++++++++++++++++++++++++++++++++-
 src/event/Queue.hpp |  2 +
 3 files changed, 122 insertions(+), 4 deletions(-)

diff --git a/src/event/Event.cpp b/src/event/Event.cpp
index 3d044e5..454f11d 100644
--- a/src/event/Event.cpp
+++ b/src/event/Event.cpp
@@ -53,8 +53,30 @@ int32_t EventIsControlKeyDown() {
 }
 
 int32_t EventIsKeyDown(KEY key) {
-    // TODO
-    return 0;
+    auto hContext = PropGet(PROP_EVENTCONTEXT);
+    auto contextId = *reinterpret_cast<uint32_t*>(hContext);
+
+    int32_t findMask;
+    auto context = TSingletonInstanceId<EvtContext, offsetof(EvtContext, m_id)>::s_idTable.Ptr(
+        contextId,
+        0,
+        &findMask
+    );
+
+    if (!context) {
+        return 0;
+    }
+
+    auto keystate = IEvtQueueCheckSyncKeyState(context, key);
+
+    if (findMask != -1) {
+        TSingletonInstanceId<EvtContext, offsetof(EvtContext, m_id)>::s_idTable.Unlock(
+            findMask & (INSTANCE_TABLE_SLOT_COUNT - 1),
+            findMask >= INSTANCE_TABLE_SLOT_COUNT
+        );
+    }
+
+    return keystate;
 }
 
 int32_t EventIsShiftKeyDown() {
diff --git a/src/event/Queue.cpp b/src/event/Queue.cpp
index 47734fb..7e61f10 100644
--- a/src/event/Queue.cpp
+++ b/src/event/Queue.cpp
@@ -3,11 +3,82 @@
 #include "event/EvtHandler.hpp"
 #include <storm/Error.hpp>
 
+void UpdateSyncMouseState(EvtContext* context, MOUSEBUTTON button, int32_t down) {
+    if (down) {
+        context->m_queueSyncButtonState |= button;
+    } else {
+        context->m_queueSyncButtonState &= ~button;
+    }
+}
+
+void UpdateSyncKeyState(EvtContext* context, KEY key, EVENTID& id) {
+    context->m_critsect.Enter();
+
+    int32_t keyDown = 0;
+
+    auto list = &context->m_queueSyncKeyDownList;
+
+    for (auto node = list->Head(); node;) {
+        if (node->key == key) {
+            keyDown = 1;
+            node = list->DeleteNode(node);
+        } else {
+            node = list->Next(node);
+        }
+    }
+
+    if (id == EVENT_ID_KEYDOWN) {
+        if (keyDown) {
+            id = EVENT_ID_KEYDOWN_REPEATING;
+        }
+
+        auto node = context->m_queueSyncKeyDownList.NewNode(2, 0, 0);
+        node->key = key;
+    }
+
+    context->m_critsect.Leave();
+}
+
+void ResetSyncState(EvtContext* context) {
+    context->m_queueSyncButtonState = 0;
+
+    context->m_critsect.Enter();
+
+    context->m_queueSyncKeyDownList.Clear();
+
+    context->m_critsect.Leave();
+}
+
+void UpdateSyncState(EvtContext* context, EVENTID& id, const void* data) {
+    STORM_VALIDATE_BEGIN;
+    STORM_VALIDATE(context);
+    STORM_VALIDATE_END_VOID;
+
+    switch (id) {
+    case EVENT_ID_FOCUS:
+        ResetSyncState(context);
+        break;
+
+    case EVENT_ID_KEYDOWN:
+    case EVENT_ID_KEYUP: {
+        auto key = reinterpret_cast<const EVENT_DATA_KEY*>(data)->key;
+        UpdateSyncKeyState(context, key, id);
+        break;
+    }
+
+    case EVENT_ID_MOUSEDOWN:
+    case EVENT_ID_MOUSEUP: {
+        auto button = reinterpret_cast<const EVENT_DATA_MOUSE*>(data)->button;
+        UpdateSyncMouseState(context, button, id == EVENT_ID_MOUSEDOWN);
+        break;
+    }
+    }
+}
+
 void IEvtQueueDispatch(EvtContext* context, EVENTID id, const void* data) {
     STORM_ASSERT(context);
 
-    // TODO
-    // UpdateSyncState(data, &id, context, v3);
+    UpdateSyncState(context, id, data);
 
     // TODO
     // if (SErrIsDisplayingError()) {
@@ -65,3 +136,26 @@ void IEvtQueueRegister(EvtContext* context, EVENTID id, int32_t (*handler)(const
 
     handlerList->LinkNode(evtHandler, 2, h);
 }
+
+int32_t IEvtQueueCheckSyncKeyState(EvtContext* context, KEY key) {
+    STORM_VALIDATE_BEGIN;
+    STORM_VALIDATE(context);
+    STORM_VALIDATE_END;
+
+    context->m_critsect.Enter();
+
+    int32_t keystate = 0;
+
+    auto list = &context->m_queueSyncKeyDownList;
+
+    for (auto node = list->Head(); node; node = list->Next(node)) {
+        if (node->key == key) {
+            keystate = 1;
+            break;
+        }
+    }
+
+    context->m_critsect.Leave();
+
+    return keystate;
+}
diff --git a/src/event/Queue.hpp b/src/event/Queue.hpp
index f916f0c..642e9f7 100644
--- a/src/event/Queue.hpp
+++ b/src/event/Queue.hpp
@@ -11,4 +11,6 @@ void IEvtQueueDispatchAll(EvtContext* context);
 
 void IEvtQueueRegister(EvtContext* context, EVENTID id, int32_t (*handler)(const void*, void*), void* param, float priority);
 
+int32_t IEvtQueueCheckSyncKeyState(EvtContext* context, KEY key);
+
 #endif