/*
 * Copyright (c) 2011      Cisco Systems, Inc.  All rights reserved.
 * Copyright (c) 2011-2013 Los Alamos National Security, LLC. All
 *                         rights reserved.
 * Copyright (c) 2014      Intel, Inc. All rights reserved.
 * $COPYRIGHT$
 * 
 * Additional copyrights may follow
 * 
 * $HEADER$
 *
 * These symbols are in a file by themselves to provide nice linker
 * semantics.  Since linkers generally pull in symbols by object
 * files, keeping these symbols as the only symbols in this file
 * prevents utility programs such as "ompi_info" from having to import
 * entire components just to query their version and parameters.
 */

#include "orte_config.h"
#include "orte/constants.h"

#include "opal/runtime/opal_params.h"
#include "opal/mca/pmix/pmix.h"
#include "opal/mca/pmix/base/base.h"

#include "orte/util/proc_info.h"

#include "orte/mca/ess/ess.h"
#include "orte/mca/ess/pmi/ess_pmi.h"

extern orte_ess_base_module_t orte_ess_pmi_module;

static int pmi_component_open(void);
static int pmi_component_close(void);
static int pmi_component_query(mca_base_module_t **module, int *priority);

/*
 * Instantiate the public struct with all of our public information
 * and pointers to our public functions in it
 */
orte_ess_base_component_t mca_ess_pmi_component = {
    {
        ORTE_ESS_BASE_VERSION_3_0_0,

        /* Component name and version */
        "pmi",
        ORTE_MAJOR_VERSION,
        ORTE_MINOR_VERSION,
        ORTE_RELEASE_VERSION,

        /* Component open and close functions */
        pmi_component_open,
        pmi_component_close,
        pmi_component_query
    },
    {
        /* The component is checkpoint ready */
        MCA_BASE_METADATA_PARAM_CHECKPOINT
    }
};

static int pmi_component_open(void)
{

    if (OPAL_SUCCESS != mca_base_framework_open(&opal_pmix_base_framework, 0)) {
        return ORTE_ERROR;
    }

    if (OPAL_SUCCESS != opal_pmix_base_select()) {
        return ORTE_ERROR;
    }

    return ORTE_SUCCESS;
}

static int pmi_component_query(mca_base_module_t **module, int *priority)
{
    /* we are available anywhere PMI is available, but not for HNP itself */
    if (!ORTE_PROC_IS_HNP && NULL != opal_pmix.init &&
        OPAL_SUCCESS == opal_pmix.init()) {
        /* if PMI is available, use it */
        *priority = 35;
        *module = (mca_base_module_t *)&orte_ess_pmi_module;
        return ORTE_SUCCESS;
    }

    /* we can't run */
    *priority = -1;
    *module = NULL;
    return ORTE_ERROR;
}


static int pmi_component_close(void)
{
    if (NULL != opal_pmix.finalize) {
        opal_pmix.finalize();  // balances query
    }
    return mca_base_framework_close(&opal_pmix_base_framework);
}