/**************************************************************************/
/*  threaded_array_processor.h                                            */
/**************************************************************************/
/*                         This file is part of:                          */
/*                             GODOT ENGINE                               */
/*                        https://godotengine.org                         */
/**************************************************************************/
/* Copyright (c) 2014-present Godot Engine contributors (see AUTHORS.md). */
/* Copyright (c) 2007-2014 Juan Linietsky, Ariel Manzur.                  */
/*                                                                        */
/* Permission is hereby granted, free of charge, to any person obtaining  */
/* a copy of this software and associated documentation files (the        */
/* "Software"), to deal in the Software without restriction, including    */
/* without limitation the rights to use, copy, modify, merge, publish,    */
/* distribute, sublicense, and/or sell copies of the Software, and to     */
/* permit persons to whom the Software is furnished to do so, subject to  */
/* the following conditions:                                              */
/*                                                                        */
/* The above copyright notice and this permission notice shall be         */
/* included in all copies or substantial portions of the Software.        */
/*                                                                        */
/* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,        */
/* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF     */
/* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. */
/* IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY   */
/* CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,   */
/* TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE      */
/* SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.                 */
/**************************************************************************/

#ifndef THREADED_ARRAY_PROCESSOR_H
#define THREADED_ARRAY_PROCESSOR_H

#include "core/os/os.h"
#include "core/os/thread.h"
#include "core/os/thread_safe.h"
#include "core/templates/safe_refcount.h"

template <class C, class U>
struct ThreadArrayProcessData {
	uint32_t elements;
	SafeNumeric<uint32_t> index;
	C *instance;
	U userdata;
	void (C::*method)(uint32_t, U);

	void process(uint32_t p_index) {
		(instance->*method)(p_index, userdata);
	}
};

template <class T>
void process_array_thread(void *ud) {
	T &data = *(T *)ud;
	while (true) {
		uint32_t index = data.index.increment();
		if (index >= data.elements) {
			break;
		}
		data.process(index);
	}
}

template <class C, class M, class U>
void thread_process_array(uint32_t p_elements, C *p_instance, M p_method, U p_userdata) {
	ThreadArrayProcessData<C, U> data;
	data.method = p_method;
	data.instance = p_instance;
	data.userdata = p_userdata;
	data.index.set(0);
	data.elements = p_elements;
	data.process(0); //process first, let threads increment for next

	int thread_count = OS::get_singleton()->get_processor_count();
	Thread *threads = memnew_arr(Thread, thread_count);

	for (int i = 0; i < thread_count; i++) {
		threads[i].start(process_array_thread<ThreadArrayProcessData<C, U>>, &data);
	}

	for (int i = 0; i < thread_count; i++) {
		threads[i].wait_to_finish();
	}
	memdelete_arr(threads);
}

#endif // THREADED_ARRAY_PROCESSOR_H