/*
 * Copyright (c) 2013      The University of Tennessee and The University
 *                         of Tennessee Research Foundation.  All rights
 *                         reserved.
 * Copyright (c) 2013      Inria.  All rights reserved.
 * Copyright (c) 2014      Intel, Inc. All rights reserved.
 * Copyright (c) 2014      Research Organization for Information Science
 *                         and Technology (RIST). All rights reserved.
 * $COPYRIGHT$
 *
 * Additional copyrights may follow
 *
 * $HEADER$
 */

#include "proc.h"
#include "opal/util/proc.h"
#include "opal/util/arch.h"
#include "opal/mca/dstore/dstore.h"
#include "opal/mca/pmix/pmix.h"

opal_process_name_t opal_name_wildcard = {OPAL_JOBID_WILDCARD, OPAL_VPID_WILDCARD};
opal_process_name_t opal_name_invalid = {OPAL_JOBID_INVALID, OPAL_VPID_INVALID};

opal_process_info_t opal_process_info = {
    .nodename = NULL,
    .job_session_dir = NULL,
    .proc_session_dir = NULL,
    .num_local_peers = 0,  /* there is nobody else but me */
    .my_local_rank = 0,    /* I'm the only process around here */
#if OPAL_HAVE_HWLOC
    .cpuset = NULL,
#endif
};

static opal_proc_t opal_local_proc = {
    { .opal_list_next = NULL,
      .opal_list_prev = NULL},
    {OPAL_JOBID_INVALID, OPAL_VPID_INVALID},
    0,
    0,
    NULL,
    NULL
};
static opal_proc_t* opal_proc_my_name = &opal_local_proc;

static void opal_proc_construct(opal_proc_t* proc)
{
    proc->proc_arch = opal_local_arch;
    proc->proc_convertor = NULL;
    proc->proc_flags = 0;
    proc->proc_name = *OPAL_NAME_INVALID;
}

static void opal_proc_destruct(opal_proc_t* proc)
{
    proc->proc_flags     = 0;
    proc->proc_name      = *OPAL_NAME_INVALID;
    proc->proc_hostname  = NULL;
    proc->proc_convertor = NULL;
}

OBJ_CLASS_INSTANCE(opal_proc_t, opal_list_item_t,
                   opal_proc_construct, opal_proc_destruct);

static int
opal_compare_opal_procs(const opal_process_name_t p1,
                        const opal_process_name_t p2)
{
    if( p1.jobid < p2.jobid ) {
        return  -1;
    }
    if( p1.jobid > p2.jobid ) {
        return  1;
    }
    if( p1.vpid <  p2.vpid ) {
        return -1;
    }
    if( p1.vpid >  p2.vpid ) {
        return 1;
    }
    return 0;
}

opal_compare_proc_fct_t opal_compare_proc = opal_compare_opal_procs;

opal_proc_t* opal_proc_local_get(void)
{
    return opal_proc_my_name;
}

int opal_proc_local_set(opal_proc_t* proc)
{
    if( proc != opal_proc_my_name ) {
        if( NULL != proc )
            OBJ_RETAIN(proc);
        if( &opal_local_proc != opal_proc_my_name )
            OBJ_RELEASE(opal_proc_my_name);
        if( NULL != proc ) {
            opal_proc_my_name = proc;
        } else {
            opal_proc_my_name = &opal_local_proc;
        }
    }
    return OPAL_SUCCESS;
}

/* this function is used to temporarily set the local
 * name while OPAL and upper layers are initializing,
 * thus allowing debug messages to be more easily
 * understood */
void opal_proc_set_name(opal_process_name_t *name)
{
    /* to protect alignment, copy the name across */
    memcpy(&opal_local_proc.proc_name, name, sizeof(opal_process_name_t));
}

/**
 * The following functions are surrogates for the RTE functionality, and are not supposed
 * to be called. Instead, the corresponding function pointer should be set by the upper layer
 * before the call to opal_init, to make them point to the correct accessors based on the
 * underlying RTE.
 */
static char*
opal_process_name_print_should_never_be_called(const opal_process_name_t procname)
{
    return "My Name is Nobody";
}

static char*
opal_vpid_print_should_never_be_called(const opal_vpid_t unused)
{
    return "My VPID";
}

static char*
opal_jobid_print_should_never_be_called(const opal_jobid_t unused)
{
    return "My JOBID";
}

static int opal_convert_string_to_process_name_should_never_be_called(opal_process_name_t *name,
                                                                      const char* name_string)
{
    return OPAL_ERR_NOT_SUPPORTED;
}

char* (*opal_process_name_print)(const opal_process_name_t) = opal_process_name_print_should_never_be_called;
char* (*opal_vpid_print)(const opal_vpid_t) = opal_vpid_print_should_never_be_called;
char* (*opal_jobid_print)(const opal_jobid_t) = opal_jobid_print_should_never_be_called;
int (*opal_convert_string_to_process_name)(opal_process_name_t *name, const char* name_string) = opal_convert_string_to_process_name_should_never_be_called;

char* opal_get_proc_hostname(const opal_proc_t *proc)
{
    int ret;

    /* if the proc is NULL, then we can't know */
    if (NULL == proc) {
        return "unknown";
    }

    /* if it is my own hostname we are after, then just hand back
     * the value in opal_process_info */
    if (proc == opal_proc_my_name) {
        return opal_process_info.nodename;
    }

    /* see if we already have the data - if so, pass it back */
    if (NULL != proc->proc_hostname) {
        return proc->proc_hostname;
    }

    /* if we don't already have it, then try to get it */
    OPAL_MODEX_RECV_VALUE(ret, OPAL_DSTORE_HOSTNAME, proc,
                          (char**)&(proc->proc_hostname), OPAL_STRING);
    if (OPAL_SUCCESS != ret) {
        OPAL_ERROR_LOG(ret);
        return "unknown";  // return something so the caller doesn't segfault
    }

    /* user is not allowed to release the data */
    return proc->proc_hostname;
}