/***
    Copyright (C) 2021 J Reece Wilson (a/k/a "Reece"). All rights reserved.

    File: AuConditionVariable.Unix.cpp
    Date: 2021-6-12
    Author: Reece
***/
#include <Source/RuntimeInternal.hpp>
#include "AuConditionVariable.Generic.hpp"
#include <Source/Time/Time.hpp>

#if !defined(_AURUNTIME_GENERICCV)

namespace Aurora::Threading::Primitives
{
    ConditionVariableImpl::ConditionVariableImpl(const AuSPtr<IConditionMutex> &mutex) : mutex_(std::dynamic_pointer_cast<IConditionMutexEx>(mutex))
    {
        pthread_condattr_t attr;
        
        ::pthread_condattr_init(&attr);
        ::pthread_condattr_setclock(&attr, CLOCK_MONOTONIC);

        auto ret = ::pthread_cond_init(&this->pthreadCv_, &attr);
        SysAssert(ret == 0, "Couldn't initialize CV");
    }
    
    ConditionVariableImpl::~ConditionVariableImpl()
    {
        ::pthread_cond_destroy(&this->pthreadCv_);
    }

    AuSPtr<IConditionMutex> ConditionVariableImpl::GetMutex()
    {
        return this->mutex_;
    }

    bool ConditionVariableImpl::WaitForSignal(AuUInt32 uTimeout)
    {
        return WaitForSignalNS(AuMSToNS<AuUInt64>(uTimeout));
    }

    bool ConditionVariableImpl::WaitForSignalNS(AuUInt64 qwTimeout)
    {
        auto mutex = reinterpret_cast<pthread_mutex_t*>(this->mutex_->GetOSHandle());

        if (gRuntimeRunLevel >= 5)
        {
            return true;
        }

        if (timeout == 0)
        {
            int ret {};
            do
            {
                if ((ret = ::pthread_cond_wait(&this->pthreadCv_, mutex)) == 0)
                {
                    return true;
                }
            } while (ret == EINTR);

            RUNTIME_ASSERT_SHUTDOWN_SAFE(false, "conditional wait failed: {}", ret)
            return false;
        }
        else
        {
            struct timespec tspec;
            Time::auabsns2ts(&tspec, AuTime::CurrentClockNS() + qwTimeout);

            int ret {};

            do
            {
                ret = ::pthread_cond_timedwait(&this->pthreadCv_, mutex, &tspec);

                if (ret == 0)
                {
                    return true;
                }

                if (ret == ETIMEDOUT)
                {
                    return false;
                }

            } while (ret == EINTR);

            RUNTIME_ASSERT_SHUTDOWN_SAFE(false, "conditional timed wait failed: {}", ret)
            return false;
        }
    }

    void ConditionVariableImpl::Signal()
    {
        auto ret = ::pthread_cond_signal(&this->pthreadCv_);
        SysAssert(ret == 0, "Couldn't wake any CV waiters");
    }

    void ConditionVariableImpl::Broadcast()
    {
        auto ret = ::pthread_cond_broadcast(&this->pthreadCv_);
        SysAssert(ret == 0, "Couldn't wake any CV waiters");
    }

    AUKN_SYM IConditionVariable *ConditionVariableNew(const AuSPtr<IConditionMutex> &mutex)
    {
        return _new ConditionVariableImpl(mutex);
    }

    AUKN_SYM void ConditionVariableRelease(IConditionVariable *mutex)
    {
        AuSafeDelete<ConditionVariableImpl *>(mutex);
    }

    AUROXTL_INTERFACE_SOO_SRC(ConditionVariable, ConditionVariableImpl, (const AuSPtr<IConditionMutex> &, pMutex))
}

#endif