From 0b79184bf36f580e5638d871c0d76fbafa0b17ea Mon Sep 17 00:00:00 2001
From: Vicki Pfau <vi@endrift.com>
Date: Mon, 24 Apr 2023 03:41:33 -0700
Subject: [PATCH] Scripting: Add lambdas that bind an object method call

---
 include/mgba/script/types.h |  1 +
 src/script/types.c          | 34 ++++++++++++++++++++++++++++++++++
 2 files changed, 35 insertions(+)

diff --git a/include/mgba/script/types.h b/include/mgba/script/types.h
index 8e3b0b560..d5a6d9947 100644
--- a/include/mgba/script/types.h
+++ b/include/mgba/script/types.h
@@ -345,6 +345,7 @@ bool mScriptObjectGetConst(const struct mScriptValue* obj, const char* member, s
 bool mScriptObjectSet(struct mScriptValue* obj, const char* member, struct mScriptValue*);
 bool mScriptObjectCast(const struct mScriptValue* input, const struct mScriptType* type, struct mScriptValue* output) ;
 void mScriptObjectFree(struct mScriptValue* obj);
+struct mScriptValue* mScriptObjectBindLambda(struct mScriptValue* obj, const char* member, struct mScriptList* args);
 
 bool mScriptPopS32(struct mScriptList* list, int32_t* out);
 bool mScriptPopU32(struct mScriptList* list, uint32_t* out);
diff --git a/src/script/types.c b/src/script/types.c
index e80c018fb..16ef78df4 100644
--- a/src/script/types.c
+++ b/src/script/types.c
@@ -1682,6 +1682,40 @@ void mScriptObjectFree(struct mScriptValue* value) {
 	}
 }
 
+struct mScriptValue* mScriptObjectBindLambda(struct mScriptValue* obj, const char* member, struct mScriptList* args) {
+	if (obj->type->base != mSCRIPT_TYPE_OBJECT) {
+		return false;
+	}
+
+	struct mScriptTypeClass* cls = obj->type->details.cls;
+	if (!cls) {
+		return false;
+	}
+
+	mScriptClassInit(cls);
+
+	struct mScriptList arguments;
+	struct mScriptValue fn;
+	if (!mScriptObjectGetConst(obj, member, &fn)) {
+		return NULL;
+	}
+
+	mScriptListInit(&arguments, 0);
+	mScriptValueWrap(obj, mScriptListAppend(&arguments));
+	if (args) {
+		size_t i;
+		for (i = 0; i < mScriptListSize(args); ++i) {
+			memcpy(mScriptListAppend(&arguments), mScriptListGetConstPointer(args, i), sizeof(struct mScriptValue));
+		}
+	}
+
+	struct mScriptValue* value = mScriptValueAlloc(fn.type);
+	struct mScriptValue* lambda = mScriptLambdaCreate0(value, &arguments);
+	mScriptValueDeref(value);
+	mScriptListDeinit(&arguments);
+	return lambda;
+}
+
 bool mScriptPopS32(struct mScriptList* list, int32_t* out) {
 	mSCRIPT_POP(list, S32, val);
 	*out = val;