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#include <QtGui>

#include "primefinder.h"

#include <QString>
#include <limits.h>
#include <stdio.h>
#include <pthread.h>
#include <errno.h>
#include <sched.h>
#include <unistd.h>

using namespace std;

PrimeFinder::PrimeFinder(PrimeApp * primeApp, int finderNum)
{
    this->primeApp = primeApp;
    this->finderNum = finderNum;
    isInterrupted = false;

    worker = new QThread;
    moveToThread(worker);
    worker->start();

    if(finderNum == 1) {
        QTextStream(stdout) << "Finder "<< finderNum << ": "
           << "Setting priority"<< endl;
        pthread_t underlying_pthread = (pthread_t)(worker->currentThreadId());
        QTextStream(stdout) << "Finder "<< finderNum << ": "
           << "Underlying pthread: "<<underlying_pthread<< endl;

        int policy;
        struct sched_param param;
        pthread_getschedparam(underlying_pthread, &policy,
                              &param);

        QTextStream(stdout) << "Finder "<< finderNum << ": "
           << "policy: "<<policy<< endl;

        QTextStream(stdout) << "Finder "<< finderNum << ": "
           << "param.__sched_priority: "<<param.__sched_priority<< endl;

        // rc: return code
        int rc = pthread_setschedprio(underlying_pthread,80);
        QTextStream(stdout) << "Finder "<< finderNum << ": "
           << "return code: "<<rc<< endl;

//        param.sched_priority = sched_get_priority_max(SCHED_FIFO);
//        param.sched_priority = sched_get_priority_min(SCHED_FIFO);
        param.sched_priority = 80; //sched_get_priority_min(SCHED_FIFO);
        rc = pthread_setschedparam(underlying_pthread,SCHED_FIFO, &param);

        pthread_getschedparam(underlying_pthread, &policy,&param);
        QTextStream(stdout) << "Finder "<< finderNum << ": "
           << "return code: "<<rc<< endl;

        QTextStream(stdout) << "EINVAL: "<<EINVAL<< endl;
        QTextStream(stdout) << "EPERM: "<<EPERM<< endl;
        QTextStream(stdout) << "ESRCH: "<<ESRCH<< endl;

        QTextStream(stdout) << "SCHED_FIFO: "<<SCHED_FIFO
         << " First in, first out (FIFO) scheduling policy."<<endl;

        QTextStream(stdout) << "SCHED_RR:" <<SCHED_RR
         <<" Round robin scheduling policy."<<endl;
//        QTextStream(stdout) << "SCHED_SPORADIC:" <<SCHED_SPORADIC<<endl;
//         <<" Sporadic server scheduling policy."<<endl;
        QTextStream(stdout) << "SCHED_OTHER:" <<SCHED_OTHER<<endl;
          //  Another scheduling policy.

        QTextStream(stdout) << "Finder "<< finderNum << ": "
           << "policy: "<<policy<< endl;

        QTextStream(stdout) << "Finder "<< finderNum << ": "
           << "param.__sched_priority: "<<param.__sched_priority<< endl;

        QThread::currentThread()->setPriority(QThread::HighPriority);

        QTextStream(stdout) << "Finder "<< finderNum << ": "
           << "Set own priority to HighPriority "<<endl;

    }

    connect(this, SIGNAL(newPrimeText(int,QString)), primeApp, SLOT(setRecentPrime(int,QString)));
}

void PrimeFinder::findPrimes()
{
    isInterrupted = false;
    for(long candidate = 100000000; candidate<LONG_MAX && !isInterrupted; candidate++) {
        if(isPrime(candidate)) {
            primes.append(candidate);
            QString text = QString("Latest prime: %1").arg(candidate);
            emit newPrimeText(finderNum, text);
            usleep(100);
            QTextStream(stdout) << text << endl
               << "findPrimes(): isInterrupted: " << isInterrupted << endl;
        }
    }
}

bool PrimeFinder::isPrime(long candidate)
{
    bool isPrime = true;
    for(int divisor = 2; divisor < candidate && isPrime; divisor++) {
        if(candidate % divisor == 0) {
            isPrime = false;
        }
    }
    return isPrime;
}

void PrimeFinder::interrupt() {
    QTextStream(stdout) << "interrupting" << endl;
    isInterrupted = true;
    QTextStream(stdout) << "interrupt(): isInterrupted: " << isInterrupted << endl;
}