/* Copyright (c) 2017-2026 Hans-Kristian Arntzen
 *
 * 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.
 */

#include "task_composer.hpp"

namespace Granite
{
TaskComposer::TaskComposer(ThreadGroup &group_)
	: group(group_)
{
}

void TaskComposer::set_incoming_task(TaskGroupHandle group_)
{
	current = std::move(group_);
}

TaskGroup &TaskComposer::begin_pipeline_stage()
{
	auto new_group = group.create_task();
	auto new_deps = group.create_task();
	if (current)
		group.add_dependency(*new_deps, *current);
	if (next_stage_deps)
		group.add_dependency(*new_deps, *next_stage_deps);
	next_stage_deps.reset();
	group.add_dependency(*new_group, *new_deps);

	current = std::move(new_group);
	incoming_deps = std::move(new_deps);
	return *current;
}

TaskGroup &TaskComposer::get_group()
{
	if (!current)
		return begin_pipeline_stage();
	else
		return *current;
}

TaskGroupHandle TaskComposer::get_outgoing_task()
{
	begin_pipeline_stage();
	auto ret = std::move(incoming_deps);
	incoming_deps = {};
	current = {};
	return ret;
}

TaskGroupHandle TaskComposer::get_pipeline_stage_dependency()
{
	return incoming_deps;
}

TaskGroupHandle TaskComposer::get_deferred_enqueue_handle()
{
	if (!next_stage_deps)
		next_stage_deps = group.create_task();
	return next_stage_deps;
}

ThreadGroup &TaskComposer::get_thread_group()
{
	return group;
}

void TaskComposer::add_outgoing_dependency(TaskGroup &task)
{
	group.add_dependency(task, *get_outgoing_task());
}
}
