#include "ws/base.hpp"
#include "ws/exception.hpp"
#include "ws/sys/mutex.hpp"

namespace ws {
    namespace sys {

#if defined(SYSTEM_WINDOWS)

        Mutex::Mutex(): locked(false){
            mutexHandle = CreateMutex(NULL, FALSE, NULL);
            if(!mutexHandle)
                throw Exception("failed to retrieve mutex");
        }

        void Mutex::lock(){
            switch(WaitForSingleObject(mutexHandle, 2000)){
                case WAIT_TIMEOUT:
                    throw Exception("mutex did not get lock in time (2 seconds maximum)");
                case WAIT_ABANDONED:
                    throw Exception("mutex owner thread quit without unlocking.");
                case WAIT_FAILED:
                    throw Exception("mutex failed with error " + GetLastError());
            }
            locked = true;
        }

        void Mutex::unlock(){
            locked = false;
            ReleaseMutex(mutexHandle);
        }

#elif defined(SYSTEM_LINUX)

        Mutex::Mutex(): locked(false){
            mutexHandle = PTHREAD_MUTEX_INITIALIZER;
            if(pthread_mutex_init(&mutexHandle, 0) == -1)
                throw Exception("mutex creation failed");

        }

        void Mutex::lock(){
            if(pthread_mutex_lock(&mutexHandle) == -1)
                throw Exception("failed to lock");
        }

        void Mutex::unlock(){
            if(pthread_mutex_unlock(&mutexHandle) == -1)
                throw Exception("failed to unlock");
        }

#endif

        scopeLock::scopeLock(Mutex& m){
            mutex = &m;
            mutex->lock();
        }

        scopeLock::~scopeLock(){
            if(mutex->locked)
                mutex->unlock();
        }

        void scopeLock::unlock(){
            if(mutex->locked)
                mutex->unlock();
        }
    }
}