/*
 * Copyright (c) 2011      Cisco Systems, Inc.  All rights reserved.
 * Copyright (c) 2011      Los Alamos National Security, LLC. 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 <pmi.h>
#if WANT_CRAY_PMI2_EXT
#include <pmi2.h>
#endif

#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);

static bool started_by_me=false;

/*
 * 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_2_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)
{
    return ORTE_SUCCESS;
}

static bool pmi_startup(void)
{
#if WANT_CRAY_PMI2_EXT
    int spawned, size, rank, appnum;

    if (PMI2_Initialized()) {
        /* already initialized */
        return true;
    }
    /* if we can't startup PMI, we can't be used */
    if (PMI_SUCCESS != PMI2_Init(&spawned, &size, &rank, &appnum)) {
        return false;
    }
    /* flag that we started PMI */
    started_by_me = true;
    /* ignore the info - we'll pick it up elsewhere */
    return true;
#else
    PMI_BOOL initialized;

    if (PMI_SUCCESS != PMI_Initialized(&initialized)) {
        return false;
    }
    if (PMI_TRUE != initialized) {
        if (PMI_SUCCESS != PMI_Init(&initialized)) {
            return false;
        }
        /* flag that we started PMI */
        started_by_me = true;
    }
    return true;
#endif
}

static int pmi_component_query(mca_base_module_t **module, int *priority)
{
    /* for now, only use PMI when direct launched */
    if (!ORTE_PROC_IS_HNP &&
        NULL == orte_process_info.my_hnp_uri &&
        pmi_startup()) {
        /* if PMI is available, use it */
        *priority = 100;
        *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 WANT_CRAY_PMI2_EXT
    if (started_by_me && PMI2_Initialized()) {
        PMI2_Finalize();
    }
#else
    PMI_BOOL initialized;

    /* if we weren't selected, cleanup */
    if (started_by_me &&
        PMI_SUCCESS == PMI_Initialized(&initialized) &&
        PMI_TRUE == initialized) {
        PMI_Finalize();
    }
#endif

    return ORTE_SUCCESS;
}