/*****************************************************************************/
// multiproc.hh
#ifndef MULTIPROC_HH
#define MULTIPROC_HH

#include <QObject>
#include <QtCore>
#include <iostream>
#include "node.hh"

class MultiProc: public QObject {
	Q_OBJECT
public:
	MultiProc(QObject *parent = 0):
		QObject(parent) {
		std::cout << "MultiProc\n";

		QList<QStringList> args;
		args << (QStringList() << "/usr/bin/echo" << "Proc 0 running");
		args << (QStringList() << "/usr/bin/echo" << "Proc 1 running");
		args << (QStringList() << "/usr/bin/cat");
		args << (QStringList() << "/usr/bin/cat");
		args << (QStringList() << "/usr/bin/tee" << "/etc/hostname");

		for (int i = 0; i < args.size(); ++i)
			_nodes << new Node(this, i, args[i]);
	}
signals:
	void finished();
public slots:
	void run() {
		std::cout << "Starting all nodes :)\n";
		foreach (Node *n, _nodes)
			n->start();
	}
private:
	QList<Node *> _nodes;
};

#endif // MULTIPROC_HH

/*****************************************************************************/
// node.hh
#ifndef NODE_HH
#define NODE_HH

#include <QtCore>
#include <iostream>

class Node: public QObject {
	Q_OBJECT
public:
	Node(QObject *parent, int id, const QStringList &args):
		QObject(parent),
		_id(id),
		_proc(new QProcess(this)),
		_args(args) {
		std::cout << "Node " << _id << " created with command "
				  << args.join(" ").toStdString() << "\n";
		connect(_proc, SIGNAL(started()), this, SLOT(started()));
		connect(_proc, SIGNAL(finished(int)), this, SLOT(finished()));
		connect(_proc, SIGNAL(readyRead()), this, SLOT(readyRead()));
		connect(_proc, SIGNAL(error(QProcess::ProcessError)),
				this, SLOT(error(QProcess::ProcessError)));
	}
	void start() {
		if (_proc->state() == QProcess::NotRunning) {
			std::cout << "Starting process on node: " << _id << "\n";
			_proc->start(_args.at(0), _args.mid(1));
		}
	}
public slots:
	void started() { std::cout << "Node " << _id << " started\n"; }
	void finished() { std::cout << "Node " << _id << " finished\n"; }
	void readyRead() { std::cout << "Node " << _id << " readyRead\n"; }
	void error(QProcess::ProcessError err) {
		std::cout << "Node " << _id << " Error: " << err << "\n";
		QCoreApplication::exit(1);
	}
private:
	int _id;
	QProcess *_proc;
	QStringList _args;
};

#endif // NODE_HH

/*****************************************************************************/
// main.cpp
#include <QCoreApplication>
#include "multiproc.hh"

int main(int argc, char *argv[]) {
	QCoreApplication a(argc, argv);

	MultiProc *p = new MultiProc(&a);
	QObject::connect(p, SIGNAL(finished()), &a, SLOT(quit()));
	QTimer::singleShot(0, p, SLOT(run()));
	return a.exec();
}