#include <EGL/egl.h>
#include <android/log.h>
#include <jni.h>

#include <stdexcept>

#include "emulator.hpp"
#include "renderer_gl/renderer_gl.hpp"
#include "services/hid.hpp"

std::unique_ptr<Emulator> emulator = nullptr;
HIDService* hidService = nullptr;
RendererGL* renderer = nullptr;
bool romLoaded = false;
JavaVM* jvm = nullptr;

#define AlberFunction(type, name) JNIEXPORT type JNICALL Java_com_panda3ds_pandroid_AlberDriver_##name

void throwException(JNIEnv* env, const char* message) {
	jclass exceptionClass = env->FindClass("java/lang/RuntimeException");
	env->ThrowNew(exceptionClass, message);
}

JNIEnv* jniEnv() {
	JNIEnv* env;
	auto status = jvm->GetEnv((void**)&env, JNI_VERSION_1_6);
	if (status == JNI_EDETACHED) {
		jvm->AttachCurrentThread(&env, nullptr);
	} else if (status != JNI_OK) {
		throw std::runtime_error("Failed to obtain JNIEnv from JVM!!");
	}

	return env;
}

extern "C" {

#define MAKE_SETTING(functionName, type, settingName) \
AlberFunction(void, functionName) (JNIEnv* env, jobject obj, type value) { emulator->getConfig().settingName = value; }

MAKE_SETTING(setShaderJitEnabled, jboolean, shaderJitEnabled)

#undef MAKE_SETTING

AlberFunction(void, Setup)(JNIEnv* env, jobject obj) { env->GetJavaVM(&jvm); }
AlberFunction(void, Pause)(JNIEnv* env, jobject obj) { emulator->pause(); }
AlberFunction(void, Resume)(JNIEnv* env, jobject obj) { emulator->resume(); }

AlberFunction(void, Initialize)(JNIEnv* env, jobject obj) {
	emulator = std::make_unique<Emulator>();

	if (emulator->getRendererType() != RendererType::OpenGL) {
		return throwException(env, "Renderer type is not OpenGL");
	}

	renderer = static_cast<RendererGL*>(emulator->getRenderer());
	hidService = &emulator->getServiceManager().getHID();

	if (!gladLoadGLES2Loader(reinterpret_cast<GLADloadproc>(eglGetProcAddress))) {
		return throwException(env, "Failed to load OpenGL ES 2.0");
	}

	__android_log_print(ANDROID_LOG_INFO, "AlberDriver", "OpenGL ES %d.%d", GLVersion.major, GLVersion.minor);
	emulator->initGraphicsContext(nullptr);
}

AlberFunction(void, RunFrame)(JNIEnv* env, jobject obj, jint fbo) {
	renderer->setFBO(fbo);
	// TODO: don't reset entire state manager
	renderer->resetStateManager();
	emulator->runFrame();

	hidService->updateInputs(emulator->getTicks());
}

AlberFunction(void, Finalize)(JNIEnv* env, jobject obj) {
	emulator = nullptr;
	hidService = nullptr;
	renderer = nullptr;
}

AlberFunction(jboolean, HasRomLoaded)(JNIEnv* env, jobject obj) { return romLoaded; }

AlberFunction(void, LoadRom)(JNIEnv* env, jobject obj, jstring path) {
	const char* pathStr = env->GetStringUTFChars(path, nullptr);
	romLoaded = emulator->loadROM(pathStr);
	env->ReleaseStringUTFChars(path, pathStr);
}

AlberFunction(void, LoadLuaScript)(JNIEnv* env, jobject obj, jstring script) {
	const char* scriptStr = env->GetStringUTFChars(script, nullptr);
	emulator->getLua().loadString(scriptStr);
	env->ReleaseStringUTFChars(script, scriptStr);
}

AlberFunction(void, TouchScreenDown)(JNIEnv* env, jobject obj, jint x, jint y) { hidService->setTouchScreenPress((u16)x, (u16)y); }
AlberFunction(void, TouchScreenUp)(JNIEnv* env, jobject obj) { hidService->releaseTouchScreen(); }
AlberFunction(void, KeyUp)(JNIEnv* env, jobject obj, jint keyCode) { hidService->releaseKey((u32)keyCode); }
AlberFunction(void, KeyDown)(JNIEnv* env, jobject obj, jint keyCode) { hidService->pressKey((u32)keyCode); }

AlberFunction(void, SetCirclepadAxis)(JNIEnv* env, jobject obj, jint x, jint y) {
	hidService->setCirclepadX((s16)x);
	hidService->setCirclepadY((s16)y);
}

AlberFunction(jbyteArray, GetSmdh)(JNIEnv* env, jobject obj) {
	std::span<u8> smdh = emulator->getSMDH();

	jbyteArray result = env->NewByteArray(smdh.size());
	env->SetByteArrayRegion(result, 0, smdh.size(), (jbyte*)smdh.data());

	return result;
}
}

#undef AlberFunction