/*
 * Copyright (c) 2004-2010 The Trustees of Indiana University and Indiana
 *                         University Research and Technology
 *                         Corporation.  All rights reserved.
 * Copyright (c) 2004-2011 The University of Tennessee and The University
 *                         of Tennessee Research Foundation.  All rights
 *                         reserved.
 * Copyright (c) 2004-2005 High Performance Computing Center Stuttgart,
 *                         University of Stuttgart.  All rights reserved.
 * Copyright (c) 2004-2005 The Regents of the University of California.
 *                         All rights reserved.
 * Copyright (c) 2006-2013 Los Alamos National Security, LLC.
 *                         All rights reserved.
 * Copyright (c) 2009-2012 Cisco Systems, Inc.  All rights reserved.
 * Copyright (c) 2011      Oak Ridge National Labs.  All rights reserved.
 * Copyright (c) 2013-2018 Intel, Inc.  All rights reserved.
 * Copyright (c) 2015      Mellanox Technologies, Inc.  All rights reserved.
 * $COPYRIGHT$
 *
 * Additional copyrights may follow
 *
 * $HEADER$
 *
 */

#include <stdbool.h>
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <time.h>
#include <pthread.h>

#include <pmix.h>

typedef struct {
    pthread_mutex_t mutex;
    pthread_cond_t cond;
    volatile bool active;
    pmix_status_t status;
} mylock_t;

#define DEBUG_CONSTRUCT_LOCK(l)                     \
    do {                                            \
        pthread_mutex_init(&(l)->mutex, NULL);      \
        pthread_cond_init(&(l)->cond, NULL);        \
        (l)->active = true;                         \
        (l)->status = PMIX_SUCCESS;                 \
    } while(0)

#define DEBUG_DESTRUCT_LOCK(l)              \
    do {                                    \
        pthread_mutex_destroy(&(l)->mutex); \
        pthread_cond_destroy(&(l)->cond);   \
    } while(0)

#define DEBUG_WAIT_THREAD(lck)                                      \
    do {                                                            \
        pthread_mutex_lock(&(lck)->mutex);                          \
        while ((lck)->active) {                                     \
            pthread_cond_wait(&(lck)->cond, &(lck)->mutex);         \
        }                                                           \
        pthread_mutex_unlock(&(lck)->mutex);                        \
    } while(0)

#define DEBUG_WAKEUP_THREAD(lck)                        \
    do {                                                \
        pthread_mutex_lock(&(lck)->mutex);              \
        (lck)->active = false;                          \
        pthread_cond_broadcast(&(lck)->cond);           \
        pthread_mutex_unlock(&(lck)->mutex);            \
    } while(0)


static pmix_proc_t myproc;

static void notification_fn(size_t evhdlr_registration_id,
                            pmix_status_t status,
                            const pmix_proc_t *source,
                            pmix_info_t info[], size_t ninfo,
                            pmix_info_t results[], size_t nresults,
                            pmix_event_notification_cbfunc_fn_t cbfunc,
                            void *cbdata)
{
    fprintf(stderr, "Client %s:%d NOTIFIED with status %d\n", myproc.nspace, myproc.rank, status);
}

static void op_callbk(pmix_status_t status,
                      void *cbdata)
{
    mylock_t *lock = (mylock_t*)cbdata;

    fprintf(stderr, "Client %s:%d OP CALLBACK CALLED WITH STATUS %d\n", myproc.nspace, myproc.rank, status);
    lock->status = status;
    DEBUG_WAKEUP_THREAD(lock);
}

static void errhandler_reg_callbk(pmix_status_t status,
                                  size_t errhandler_ref,
                                  void *cbdata)
{
    mylock_t *lock = (mylock_t*)cbdata;

    fprintf(stderr, "Client %s:%d ERRHANDLER REGISTRATION CALLBACK CALLED WITH STATUS %d, ref=%lu\n",
               myproc.nspace, myproc.rank, status, (unsigned long)errhandler_ref);
    lock->status = status;
    DEBUG_WAKEUP_THREAD(lock);
}

int main(int argc, char **argv)
{
    int rc;
    pmix_value_t value;
    pmix_value_t *val = &value;
    pmix_proc_t proc, *procs;
    uint32_t nprocs;
    mylock_t lock;
    pmix_info_t *results, info;
    size_t nresults, cid;

    /* init us */
    if (PMIX_SUCCESS != (rc = PMIx_Init(&myproc, NULL, 0))) {
        fprintf(stderr, "Client ns %s rank %d: PMIx_Init failed: %s\n", myproc.nspace, myproc.rank, PMIx_Error_string(rc));
        exit(0);
    }
    fprintf(stderr, "Client ns %s rank %d: Running\n", myproc.nspace, myproc.rank);

    PMIX_PROC_CONSTRUCT(&proc);
    (void)strncpy(proc.nspace, myproc.nspace, PMIX_MAX_NSLEN);
    proc.rank = PMIX_RANK_WILDCARD;

    /* get our universe size */
    if (PMIX_SUCCESS != (rc = PMIx_Get(&proc, PMIX_UNIV_SIZE, NULL, 0, &val))) {
        fprintf(stderr, "Client ns %s rank %d: PMIx_Get universe size failed: %s\n", myproc.nspace, myproc.rank, PMIx_Error_string(rc));
        goto done;
    }
    nprocs = val->data.uint32;
    PMIX_VALUE_RELEASE(val);
    if (nprocs < 4) {
        if (0 == myproc.rank) {
            fprintf(stderr, "This example requires a minimum of 4 processes\n");
        }
        goto done;
    }
    fprintf(stderr, "Client %s:%d universe size %d\n", myproc.nspace, myproc.rank, nprocs);

    /* register our default errhandler */
    DEBUG_CONSTRUCT_LOCK(&lock);
    PMIx_Register_event_handler(NULL, 0, NULL, 0,
                                notification_fn, errhandler_reg_callbk, (void*)&lock);
    DEBUG_WAIT_THREAD(&lock);
    rc = lock.status;
    DEBUG_DESTRUCT_LOCK(&lock);
    if (PMIX_SUCCESS != rc) {
        goto done;
    }

    /* call fence to sync */
    PMIX_PROC_CONSTRUCT(&proc);
    (void)strncpy(proc.nspace, myproc.nspace, PMIX_MAX_NSLEN);
    proc.rank = PMIX_RANK_WILDCARD;
    if (PMIX_SUCCESS != (rc = PMIx_Fence(&proc, 1, NULL, 0))) {
        fprintf(stderr, "Client ns %s rank %d: PMIx_Fence failed: %d\n", myproc.nspace, myproc.rank, rc);
        goto done;
    }

    /* rank=0,2,3 construct a new group */
    if (0 == myproc.rank || 2 == myproc.rank || 3 == myproc.rank) {
        fprintf(stderr, "%d executing Group_construct\n", myproc.rank);
        nprocs = 3;
        PMIX_PROC_CREATE(procs, nprocs);
        PMIX_PROC_LOAD(&procs[0], myproc.nspace, 0);
        PMIX_PROC_LOAD(&procs[1], myproc.nspace, 2);
        PMIX_PROC_LOAD(&procs[2], myproc.nspace, 3);
        PMIX_INFO_LOAD(&info, PMIX_GROUP_ASSIGN_CONTEXT_ID, NULL, PMIX_BOOL);
        rc = PMIx_Group_construct("ourgroup", procs, nprocs, &info, 1, &results, &nresults);
        if (PMIX_SUCCESS != rc) {
            fprintf(stderr, "Client ns %s rank %d: PMIx_Group_construct failed: %s\n", myproc.nspace, myproc.rank, PMIx_Error_string(rc));
            goto done;
        }
        /* we should have a single results object */
        if (NULL != results) {
            cid = 0;
            PMIX_VALUE_GET_NUMBER(rc, &results[0].value, cid, size_t);
            fprintf(stderr, "%d Group construct complete with status %s KEY %s CID %d\n",
                    myproc.rank, PMIx_Error_string(rc), results[0].key, (int)cid);
        } else {
            fprintf(stderr, "%d Group construct complete, but no CID returned\n", myproc.rank);
        }
        PMIX_PROC_FREE(procs, nprocs);
        fprintf(stderr, "%d executing Group_destruct\n", myproc.rank);
        rc = PMIx_Group_destruct("ourgroup", NULL, 0);
        if (PMIX_SUCCESS != rc) {
            fprintf(stderr, "Client ns %s rank %d: PMIx_Group_destruct failed: %s\n", myproc.nspace, myproc.rank, PMIx_Error_string(rc));
            goto done;
        }
    }

 done:
    /* finalize us */
    DEBUG_CONSTRUCT_LOCK(&lock);
    PMIx_Deregister_event_handler(1, op_callbk, &lock);
    DEBUG_WAIT_THREAD(&lock);
    DEBUG_DESTRUCT_LOCK(&lock);

    fprintf(stderr, "Client ns %s rank %d: Finalizing\n", myproc.nspace, myproc.rank);
    if (PMIX_SUCCESS != (rc = PMIx_Finalize(NULL, 0))) {
        fprintf(stderr, "Client ns %s rank %d:PMIx_Finalize failed: %s\n", myproc.nspace, myproc.rank, PMIx_Error_string(rc));
    } else {
        fprintf(stderr, "Client ns %s rank %d:PMIx_Finalize successfully completed\n", myproc.nspace, myproc.rank);
    }
    fprintf(stderr, "%s:%d COMPLETE\n", myproc.nspace, myproc.rank);
    fflush(stderr);
    return(0);
}