#include "piplatform.h"
#include "piconditionvar.h"
#include "pithread.h"
#include "pitime.h"

#ifdef WINDOWS
#undef _WIN32_WINNT
#define _WIN32_WINNT 0x0600
#include "synchapi.h"
#include <windef.h>
#include <winbase.h>
#endif


PRIVATE_DEFINITION_START(PIConditionVariable)
#ifdef WINDOWS
CONDITION_VARIABLE nativeHandle;
#else
pthread_cond_t nativeHandle;
PIConditionLock* currentLock;
#endif
bool isDestroying;
PRIVATE_DEFINITION_END(PIConditionVariable)


PIConditionVariable::PIConditionVariable() {
#ifdef WINDOWS
	InitializeConditionVariable(&PRIVATE->nativeHandle);
#else
	PRIVATE->isDestroying = false;
	PRIVATE->currentLock = nullptr;
	memset(&(PRIVATE->nativeHandle), 0, sizeof(PRIVATE->nativeHandle));
	pthread_cond_init(&PRIVATE->nativeHandle, NULL);
#endif
}


PIConditionVariable::~PIConditionVariable() {
#ifdef WINDOWS
#else
	pthread_cond_destroy(&PRIVATE->nativeHandle);
#endif
}


void PIConditionVariable::wait(PIConditionLock& lk) {
#ifdef WINDOWS
	SleepConditionVariableCS(&PRIVATE->nativeHandle, (PCRITICAL_SECTION)lk.handle(), INFINITE);
#else
	pthread_cond_wait(&PRIVATE->nativeHandle, (pthread_mutex_t*)lk.handle());
#endif
}


void PIConditionVariable::wait(PIConditionLock& lk, const std::function<bool()>& condition) {
	bool isCondition;
	while (true) {
		isCondition = condition();
		if (isCondition) break;
#ifdef WINDOWS
		SleepConditionVariableCS(&PRIVATE->nativeHandle, (PCRITICAL_SECTION)lk.handle(), INFINITE);
#else
		pthread_cond_wait(&PRIVATE->nativeHandle, (pthread_mutex_t*)lk.handle());
#endif
		if (PRIVATE->isDestroying) return;
	}
}


bool PIConditionVariable::waitFor(PIConditionLock &lk, int timeoutMs) {
	bool isNotTimeout;
#ifdef WINDOWS
	isNotTimeout = SleepConditionVariableCS(&PRIVATE->nativeHandle, (PCRITICAL_SECTION)lk.handle(), timeoutMs) != 0;
#else
	timespec abstime = {.tv_sec = timeoutMs / 1000, .tv_nsec = timeoutMs * 1000 * 1000};
	isNotTimeout = pthread_cond_timedwait(&PRIVATE->nativeHandle, (pthread_mutex_t*)lk.handle(), &abstime) == 0;
#endif
	if (PRIVATE->isDestroying) return false;
	return isNotTimeout;
}


bool PIConditionVariable::waitFor(PIConditionLock& lk, int timeoutMs, const std::function<bool()> &condition) {
	bool isCondition;
	PITimeMeasurer measurer;
	while (true) {
		isCondition = condition();
		if (isCondition) break;
#ifdef WINDOWS
		WINBOOL isTimeout = SleepConditionVariableCS(
					&PRIVATE->nativeHandle,
					(PCRITICAL_SECTION)lk.handle(),
					timeoutMs - (int)measurer.elapsed_m());
		if (isTimeout == 0) return false;
#else
		int timeoutCurr = timeoutMs - (int)measurer.elapsed_m();
		timespec abstime = {.tv_sec = timeoutCurr / 1000, .tv_nsec = timeoutCurr * 1000 * 1000};
		bool isTimeout = pthread_cond_timedwait(&PRIVATE->nativeHandle, (pthread_mutex_t*)lk.handle(), &abstime) == 0;
		if (isTimeout) return false;
#endif
		if (PRIVATE->isDestroying) return false;
	}
	return true;
}


void PIConditionVariable::notifyOne() {
#ifdef WINDOWS
	WakeConditionVariable(&PRIVATE->nativeHandle);
#else
	pthread_cond_signal(&PRIVATE->nativeHandle);
#endif
}


void PIConditionVariable::notifyAll() {
#ifdef WINDOWS
	WakeAllConditionVariable(&PRIVATE->nativeHandle);
#else
	pthread_cond_broadcast(&PRIVATE->nativeHandle);
#endif
}