#ifndef AL_THREADS_H
#define AL_THREADS_H

#include <time.h>
#include <errno.h>


enum {
    althrd_success = 0,
    althrd_timeout,
    althrd_error,
    althrd_busy,
    althrd_nomem
};

enum {
    almtx_plain = 0,
    almtx_recursive = 1,
    almtx_timed = 2,
    almtx_normal = 4,
    almtx_errorcheck = 8
};


typedef int (*althrd_start_t)(void*);


#ifdef _WIN32
#define WIN32_LEAN_AND_MEAN
#include <windows.h>

typedef HANDLE althrd_t;
typedef CRITICAL_SECTION almtx_t;

#ifndef __MINGW32__
struct timespec {
    time_t tv_sec;
    long tv_nsec;
};
#endif


int althrd_sleep(const struct timespec *ts, struct timespec *rem);


#if 0
inline althrd_t althrd_current(void)
{
    /* This is wrong. GetCurrentThread() returns a psuedo-handle of -1 which
     * various functions will interpret as the calling thread. There is no
     * apparent way to retrieve the same handle that was returned by
     * CreateThread. */
    return GetCurrentThread();
}
#endif

inline int althrd_equal(althrd_t thr0, althrd_t thr1)
{
    return GetThreadId(thr0) == GetThreadId(thr1);
}

inline void althrd_exit(int res)
{
    ExitThread(res);
}

inline void althrd_yield(void)
{
    SwitchToThread();
}


inline int almtx_lock(almtx_t *mtx)
{
    if(!mtx) return althrd_error;
    EnterCriticalSection(mtx);
    return althrd_success;
}

inline int almtx_unlock(almtx_t *mtx)
{
    if(!mtx) return althrd_error;
    LeaveCriticalSection(mtx);
    return althrd_success;
}

inline int almtx_trylock(almtx_t *mtx)
{
    if(!mtx) return althrd_error;
    if(!TryEnterCriticalSection(mtx))
        return althrd_busy;
    return althrd_success;
}

#else

#include <stdint.h>
#include <pthread.h>


typedef pthread_t althrd_t;
typedef pthread_mutex_t almtx_t;


inline althrd_t althrd_current(void)
{
    return pthread_self();
}

inline int althrd_equal(althrd_t thr0, althrd_t thr1)
{
    return pthread_equal(thr0, thr1);
}

inline void althrd_exit(int res)
{
    pthread_exit((void*)(intptr_t)res);
}

inline void althrd_yield(void)
{
    sched_yield();
}

inline int althrd_sleep(const struct timespec *ts, struct timespec *rem)
{
    return nanosleep(ts, rem);
}


inline int almtx_lock(almtx_t *mtx)
{
    if(!mtx) return althrd_error;
    pthread_mutex_lock(mtx);
    return althrd_success;
}

inline int almtx_unlock(almtx_t *mtx)
{
    if(!mtx) return althrd_error;
    pthread_mutex_unlock(mtx);
    return althrd_success;
}

inline int almtx_trylock(almtx_t *mtx)
{
    if(!mtx) return althrd_error;
    if(pthread_mutex_trylock(mtx) != 0)
        return althrd_busy;
    return althrd_success;
}

#endif


int althrd_create(althrd_t *thr, althrd_start_t func, void *arg);
int althrd_detach(althrd_t thr);
int althrd_join(althrd_t thr, int *res);

int almtx_init(almtx_t *mtx, int type);
void almtx_destroy(almtx_t *mtx);
int almtx_timedlock(almtx_t *mtx, const struct timespec *ts);


void SetThreadName(const char *name);


inline void al_nssleep(time_t sec, long nsec)
{
    struct timespec ts, rem;
    ts.tv_sec = sec;
    ts.tv_nsec = nsec;

    while(althrd_sleep(&ts, &rem) == -1 && errno == EINTR)
        ts = rem;
}

#endif /* AL_THREADS_H */