/*
	PIP - Platform Independent Primitives

	Stephan Fomenko

	This program is free software: you can redistribute it and/or modify
	it under the terms of the GNU Lesser General Public License as published by
	the Free Software Foundation, either version 3 of the License, or
	(at your option) any later version.

	This program is distributed in the hope that it will be useful,
	but WITHOUT ANY WARRANTY; without even the implied warranty of
	MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
	GNU Lesser General Public License for more details.

	You should have received a copy of the GNU Lesser General Public License
	along with this program.  If not, see <http://www.gnu.org/licenses/>.
*/

#include "executor.h"


PIThreadPoolExecutor::PIThreadPoolExecutor(size_t corePoolSize, PIBlockingDequeue<std::function<void()>> *taskQueue_) : isShutdown_(false), taskQueue(taskQueue_) {
	for (size_t i = 0; i < corePoolSize; ++i) {
		PIThread * thread = new PIThread([&, i](){
			auto runnable = taskQueue->poll(100, std::function<void()>());
			if (runnable) {
				runnable();
			}
			if (isShutdown_ && taskQueue->size() == 0) threadPool[i]->stop();
		});
		threadPool.push_back(thread);
		thread->start();
	}
}


bool PIThreadPoolExecutor::awaitTermination(int timeoutMs) {
	PITimeMeasurer measurer;
	for (size_t i = 0; i < threadPool.size(); ++i) {
		int dif = timeoutMs - (int)measurer.elapsed_m();
		if (dif < 0) return false;
		if (!threadPool[i]->waitForFinish(dif)) return false;
	}
	return true;
}


void PIThreadPoolExecutor::shutdownNow() {
	isShutdown_ = true;
	for (size_t i = 0; i < threadPool.size(); ++i) threadPool[i]->stop();
}


PIThreadPoolExecutor::~PIThreadPoolExecutor() {
	shutdownNow();
	while (threadPool.size() > 0) delete threadPool.take_back();
	delete taskQueue;
}


void PIThreadPoolExecutor::execute(const std::function<void()> &runnable) {
	if (!isShutdown_) taskQueue->offer(runnable);
}


bool PIThreadPoolExecutor::isShutdown() const {
	return isShutdown_;
}


void PIThreadPoolExecutor::shutdown() {
	isShutdown_ = true;
}