first pass add events

3 files changed, 76 insertions, 0 deletions

diff --git a/CMakeLists.txt b/CMakeLists.txt
index e90552d..5a1851a 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -16,6 +16,8 @@ set(PKE_SOURCE_FILES
 	src/macros.hpp
 	src/ecs.hpp
 	src/ecs.cpp
+	src/event.hpp
+	src/event.cpp
 	src/game.hpp
 	src/game.cpp
 	src/memory.hpp
diff --git a/src/event.cpp b/src/event.cpp
new file mode 100644
index 0000000..4683f0e
--- /dev/null
+++ b/src/event.cpp
@@ -0,0 +1,57 @@
+
+#include "event.hpp"
+
+struct EventBucket {
+	char name[16] = {0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0};
+	DynArray<EventHandler> callbacks{8};
+};
+DynArray<EventBucket> eventBuckets{4};
+
+void EventBucketFind(const char *name, char *safeName, EventBucket*& bkt) {
+	assert(strlen(name) <= 16);
+	memset(safeName, '\0', 16);
+	memcpy(safeName, name, strlen(name));
+	for (long i = 0; i < eventBuckets.Count(); ++i) {
+		EventBucket *tmpBkt = eventBuckets.GetPtr() + (sizeof(EventBucket) * i);
+		if (strncmp(safeName, tmpBkt->name, 16) == 0) {
+			bkt = tmpBkt;
+			break;
+		}
+	}
+}
+
+void RegisterCallback(const char *name, EventHandler handler) {
+	char safeName[16];
+	EventBucket *bkt = nullptr;
+	EventBucketFind(name, safeName, bkt);
+	if (bkt == nullptr) {
+		eventBuckets.Push(EventBucket{});
+		bkt = eventBuckets.GetPtr() + (sizeof(EventBucket) * (eventBuckets.Count() - 1));
+		memcpy(bkt->name, safeName, 16);
+	}
+	bkt->callbacks.Push(handler);
+}
+
+void UnregisterCallback(const char *name, EventHandler handler) {
+	char safeName[16];
+	EventBucket *bkt = nullptr;
+	EventBucketFind(name, safeName, bkt);
+	if (bkt == nullptr) return;
+	for (uint64_t i = 0; i < bkt->callbacks.Count(); ++i) {
+		if (bkt->callbacks[i] == handler) {
+			bkt->callbacks.Remove(i);
+			break;
+		}
+	}
+}
+
+void DispatchCabllack(const char *name) {
+	char safeName[16];
+	EventBucket *bkt = nullptr;
+	EventBucketFind(name, safeName, bkt);
+	if (bkt == nullptr) return;
+	for (long i = 0; i < bkt->callbacks.Count(); ++i) {
+		bkt->callbacks[i]();
+	}
+}
+
diff --git a/src/event.hpp b/src/event.hpp
new file mode 100644
index 0000000..505d82a
--- /dev/null
+++ b/src/event.hpp
@@ -0,0 +1,17 @@
+#ifndef PKE_EVENT_HPP
+#define PKE_EVENT_HPP
+
+#include "macros.hpp"
+#include "dynamic-array.hpp"
+
+#include <cassert>
+#include <cstdint>
+#include <cstring>
+
+typedef void (*EventHandler)();
+
+void RegisterCallback(const char *name, EventHandler handler);
+void UnregisterCallback(const char *name, EventHandler handler);
+void DispatchCabllack(const char *name);
+
+#endif /* PKE_EVENT_HPP */