/*
 * Copyright (c) 2004-2008 The Trustees of Indiana University and Indiana
 *                         University Research and Technology
 *                         Corporation.  All rights reserved.
 * Copyright (c) 2004-2005 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) 2008      UT-Battelle, LLC
 * Copyright (c) 2011      Los Alamos National Security, LLC.
 *                         All rights reserved.
 * $COPYRIGHT$
 * 
 * Additional copyrights may follow
 * 
 * $HEADER$
 */

#include "orte_config.h"

#include "opal/mca/base/base.h"
#include "opal/util/output.h"
#include "opal/mca/base/mca_base_param.h"
#include "orte/constants.h"
#include "orte/util/proc_info.h"
#include "ras_alps.h"

#include <ctype.h>

/*
 * Local variables
 */
static int param_priority;
static int param_read_attempts;


/*
 * Local functions
 */
static int ras_alps_open(void);
static int orte_ras_alps_component_query(mca_base_module_t **module, int *priority);
unsigned long int orte_ras_alps_res_id;


orte_ras_base_component_t mca_ras_alps_component = {
    /* First, the mca_base_component_t struct containing meta
       information about the component itself */

    {
        ORTE_RAS_BASE_VERSION_2_0_0,
        
        /* Component name and version */
        "alps",
        ORTE_MAJOR_VERSION,
        ORTE_MINOR_VERSION,
        ORTE_RELEASE_VERSION,
        
        /* Component open and close functions */
        ras_alps_open,
        NULL,
        orte_ras_alps_component_query
    },
    {
        /* The component is checkpoint ready */
        MCA_BASE_METADATA_PARAM_CHECKPOINT
    }
};

/* simple function used to strip off characters on and after a period. NULL
 * will be returned upon failure.  Otherwise, a "prepped" string will be
 * returned.  The caller is responsible for freeing returned resources.
 * for example: if jid is 138295.sdb, then 138295 will be returned. 
 */
static char *
prep_job_id(const char *jid)
{
    char *tmp = strdup(jid);
    char *tmp2 = NULL;

    if (NULL == tmp) {
        /* out of resources */
        return NULL;
    }
    if (NULL != (tmp2 = strchr(tmp, '.'))) {
        *tmp2 = '\0';
    }
    return tmp;
}

/* this function replicates some of the id setting functionality found in
 * ras-alps-command.sh. we wanted the ability to just "mpirun" the application
 * without having to set an environment variable */
static unsigned long int 
get_res_id(void) {
    const char *apstat_cmd = "/usr/bin/apstat -r";
    char *id = NULL;
    char read_buf[512];
    FILE *apstat_fp = NULL;
    /* zero is considered to be an invalid res id */
    unsigned long jid = 0;

    if (NULL != (id = getenv("BATCH_PARTITION_ID"))) {
        return strtoul(id, NULL, 10);
    }
    if (NULL != (id = getenv("PBS_JOBID"))) {
        char *prepped_jid = prep_job_id(id);
        if (NULL == prepped_jid) {
            /* out of resources */
            return 0;
        }
        if (NULL == (apstat_fp = popen(apstat_cmd, "r"))) {
            /* popen failure */
            free(prepped_jid);
            return 0;
        }
        while (NULL != fgets(read_buf, 512, apstat_fp)) {
            /* does this line have the id that we care about? */
            if (NULL != strstr(read_buf, prepped_jid)) {
        /* the line is going to be in the form of something like:
        A 1450   571783 batch:138309     XT    80 - -   2000 conf,claim
         */
                char *t = read_buf;
                for (t = read_buf; !isdigit(*t) && *t; ++t) {
                    jid = strtoul(t, NULL, 10);
                }
                /* if we are here, then jid should be, given the example above,
                 * 1450 */
                break;
            }
        }
        fclose(apstat_fp);
        free(prepped_jid);
    }
    return jid;
}

static int ras_alps_open(void)
{
    param_priority = 
        mca_base_param_reg_int(&mca_ras_alps_component.base_version,
                               "priority",
                               "Priority of the alps ras component",
                               false, false, 75, NULL);

    param_read_attempts = 
        mca_base_param_reg_int(&mca_ras_alps_component.base_version,
                               "appinfo_read_attempts",
                               "Maximum number of attempts to read ALPS appinfo file",
                               false, false, 10, NULL);

    return ORTE_SUCCESS;
}

static int orte_ras_alps_component_query(mca_base_module_t **module, int *priority)
{
    char *jid_str = NULL;
    /* default to an invalid value */
    orte_ras_alps_res_id = 0;

    /* if we are not an HNP, then we must not be selected */
    if (!ORTE_PROC_IS_HNP) {
        *module = NULL;
        return ORTE_ERROR;
    }
    
    /* Are we running under a ALPS job? */
    /* BASIL_RESERVATION_ID is the equivalent of OMPI_ALPS_RESID
     * on some systems
     */
    if ((NULL == (jid_str = getenv("OMPI_ALPS_RESID"))) &&
        (NULL == (jid_str = getenv("BASIL_RESERVATION_ID")))) {
            orte_ras_alps_res_id = get_res_id();
    }
    else {
        orte_ras_alps_res_id = strtoul(jid_str, NULL, 10);
    }
    if (0 != orte_ras_alps_res_id) {
        mca_base_param_lookup_int(param_priority, priority);
        opal_output_verbose(1, orte_ras_base.ras_output,
                             "ras:alps: available for selection");
        *module = (mca_base_module_t *) &orte_ras_alps_module;
        return ORTE_SUCCESS;
    }

    /* Sadly, no */

    opal_output(orte_ras_base.ras_output,
                "ras:alps: NOT available for selection -- OMPI_ALPS_RESID or BASIL_RESERVATION_ID not set?");
    *module = NULL;
    return ORTE_ERROR;
}

int orte_ras_alps_get_appinfo_attempts( int *attempts ) {

    mca_base_param_lookup_int(param_read_attempts, attempts);
    opal_output_verbose(1, orte_ras_base.ras_output,
                         "ras:alps:orte_ras_alps_get_appinfo_attempts: %d", *attempts);
    return ORTE_SUCCESS;
}