#include "Critical.h"

#include <iostream>
#include <time.h>

#include "Globals.h"
#include "Thread.h"

using namespace Framework;

// Inhalt der Critical class aus Critical.h
// Konstructor
Critical::Critical()
{
    InitializeCriticalSection(&cs);
    owner = 0;
    lockCount = 0;
    id = (int)time(0);
}

// Destructor
Critical::~Critical()
{
    DeleteCriticalSection(&cs);
}

pthread_t CachedCurrentThread()
{
    volatile thread_local static  pthread_t t = GetCurrentThread();
    return (pthread_t)t;
}

// sperrt das Objekt
void Critical::lock()
{
    getThreadRegister()->lock();
    Thread* tmp = getThreadRegister()->zThread(CachedCurrentThread());
    if (tmp) tmp->addCriticalLock();
    getThreadRegister()->unlock();
    EnterCriticalSection(&cs);
    if (!owner) owner = tmp;
    lockCount++;
}

// versucht das Objekt zu sperren
bool Critical::tryLock()
{
    if (lockCount > 0) return false;
    getThreadRegister()->lock();
    Thread* tmp = getThreadRegister()->zThread(CachedCurrentThread());
    if (tmp) tmp->addCriticalLock();
    getThreadRegister()->unlock();
    EnterCriticalSection(&cs);
    if (!owner) owner = tmp;
    lockCount++;
    return true;
}

// entsperrt das Objekt
void Critical::unlock()
{
    getThreadRegister()->lock();
    Thread* tmp = 0;
    if (getThreadRegister()->isThread(owner))
    {
        if (owner
            && GetThreadId(owner->getThreadHandle())
                   != GetThreadId(CachedCurrentThread()))
            throw std::runtime_error("A Thread that does not own a Critical "
                                     "Object trys to unlock it");
        tmp = owner;
    }
    getThreadRegister()->unlock();
    if (!--lockCount) owner = 0;
    LeaveCriticalSection(&cs);
    getThreadRegister()->lock();
    if (tmp && getThreadRegister()->isThread(tmp)) tmp->removeCriticalLock();
    getThreadRegister()->unlock();
}

// gibt true zurück, wenn das Objekt gesperrt ist
bool Critical::isLocked() const
{
    return lockCount > 0;
}

// gibt einen Zeiger auf den Thread zurück, der das Objekt gesperrt hat
const Thread* Critical::zOwner() const
{
    return owner;
}

Synchronizer::Synchronizer()
    : numWaiting(0),
      skip(0)
{}

Synchronizer::~Synchronizer()
{
    skip = 1;
    std::unique_lock<std::mutex> lk(mutex);
    if (numWaiting > 0)
    {
        lk.unlock();
        block.notify_all();
    }
    else
        lk.unlock();
    while (numWaiting > 0)
        Sleep(10);
    lk.lock();
}

bool Synchronizer::wait()
{
    std::unique_lock<std::mutex> lk(mutex);
    if (skip) return false;
    numWaiting++;
    block.wait(lk);
    numWaiting--;
    return !skip;
}

bool Synchronizer::wait(int milisec)
{
    std::unique_lock<std::mutex> lk(mutex);
    if (skip) return false;
    numWaiting++;
    std::cv_status status
        = block.wait_for(lk, std::chrono::milliseconds(milisec));
    numWaiting--;
    return !skip && status == std::cv_status::no_timeout;
}

void Synchronizer::notify()
{
    block.notify_one();
}

void Synchronizer::notify(int amount)
{
    while (amount--)
        block.notify_one();
}

void Synchronizer::notifyAll()
{
    block.notify_all();
}

int Synchronizer::getNumberOfWaitingThreads() const
{
    return numWaiting;
}