/*
 * Copyright (c) 2004-2005 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) 2013-2019 University of Houston. All rights reserved.
 * Copyright (c) 2015-2018 Research Organization for Information Science
 *                         and Technology (RIST). All rights reserved.
 * Copyright (c) 2016-2017 IBM Corporation. All rights reserved.
 * $COPYRIGHT$
 *
 * Additional copyrights may follow
 *
 * $HEADER$
 */


#include "ompi_config.h"
#include "sharedfp_individual.h"

#include "mpi.h"
#include "ompi/constants.h"
#include "ompi/mca/sharedfp/sharedfp.h"
#include "ompi/mca/sharedfp/base/base.h"
#include "ompi/file/file.h"


int mca_sharedfp_individual_file_open (struct ompi_communicator_t *comm,
				       const char* filename,
				       int amode,
				       struct opal_info_t *info,
				       ompio_file_t *fh)
{
    int err = 0;
    char * datafilename;	/*The array size would change as it is based on the current path*/
    char * metadatafilename;	/*The array size would change as it is based on the current path*/
    ompio_file_t * datafilehandle;
    ompio_file_t * metadatafilehandle;
    mca_sharedfp_individual_header_record* headnode = NULL;
    struct mca_sharedfp_base_data_t* sh;
    size_t len=0;

    sh = (struct mca_sharedfp_base_data_t*) malloc ( sizeof(struct mca_sharedfp_base_data_t));
    if ( NULL == sh ){
        opal_output(0, "mca_sharedfp_individual_file_open: Error, unable to malloc "
		    "f_sharedfp_ptr struct\n");
        return OMPI_ERR_OUT_OF_RESOURCE;
    }


    /*Populate the sh file structure based on the implementation*/
    sh->global_offset = 0;			/* Global Offset*/
    sh->selected_module_data = NULL;

    /* Assign the metadatalinked list to sh->handle */
    sh->selected_module_data = (mca_sharedfp_individual_header_record *)mca_sharedfp_individual_insert_headnode();

    /*--------------------------------------------------------*/
    /* Open an individual data file for each process          */
    /* NOTE: Open the data file without shared file pointer   */
    /*--------------------------------------------------------*/
    if ( mca_sharedfp_individual_verbose ) {
       opal_output(ompi_sharedfp_base_framework.framework_output,
                "mca_sharedfp_individual_file_open: open data file.\n");
    }

    /* data filename created by appending .data.$rank to the original filename*/
    len = strlen (filename ) + 64;
    datafilename = (char*)malloc( len );
    if ( NULL == datafilename ) {
        opal_output(0, "mca_sharedfp_individual_file_open: unable to allocate memory\n");
        free ( sh );
        return OMPI_ERR_OUT_OF_RESOURCE;
    }
    snprintf(datafilename, len, "%s%s%d",filename,".data.",fh->f_rank);


    datafilehandle = (ompio_file_t *)malloc(sizeof(ompio_file_t));
    if ( NULL == datafilehandle ) {
        opal_output(0, "mca_sharedfp_individual_file_open: unable to allocate memory\n");
        free ( sh );
        free ( datafilename );
        return OMPI_ERR_OUT_OF_RESOURCE;
    }
    err = mca_common_ompio_file_open(MPI_COMM_SELF, datafilename,
                                     MPI_MODE_RDWR | MPI_MODE_CREATE | MPI_MODE_DELETE_ON_CLOSE,
                                     &(MPI_INFO_NULL->super), datafilehandle, false);
    if ( OMPI_SUCCESS != err) {
       opal_output(ompi_sharedfp_base_framework.framework_output,
                   "mca_sharedfp_individual_file_open: Error during datafile file open. Continuing anyway. \n");
        free (sh);
	free (datafilename);
        free (datafilehandle);

        // We reset the error code here to OMPI_SUCCESS since the individual component can act as
        // a dummy component, in case no sharedfp operations are used by the code. Invoking any write/read
        // operations will however lead to an error, since the sharedfp_data pointer will be NULL.
        sh = NULL;
        err = OMPI_SUCCESS;
        goto exit;
    }

    /*----------------------------------------------------------*/
    /* Open an individual metadata file for each of the process */
    /* NOTE: Open the meta file without shared file pointer     */
    /*----------------------------------------------------------*/
    if ( mca_sharedfp_individual_verbose ) {
        opal_output(ompi_sharedfp_base_framework.framework_output,
                "mca_sharedfp_individual_file_open: metadata file.\n");
    }

    /* metadata filename created by appending .metadata.$rank to the original filename*/
    metadatafilename = (char*) malloc ( len );
    if ( NULL == metadatafilename ) {
        free (sh);
	free (datafilename);
        mca_common_ompio_file_close ( datafilehandle);
        free (datafilehandle);
        opal_output(0, "mca_sharedfp_individual_file_open: Error during memory allocation\n");

        sh=NULL;
        err = OMPI_ERR_OUT_OF_RESOURCE;
        goto exit;
    }
    snprintf ( metadatafilename, len, "%s%s%d", filename, ".metadata.",fh->f_rank);

    metadatafilehandle = (ompio_file_t *)malloc(sizeof(ompio_file_t));
    if ( NULL == metadatafilehandle ) {
        free (sh);
        free (datafilename);
        mca_common_ompio_file_close ( datafilehandle);
        free (datafilehandle);
        free (metadatafilename);
        opal_output(0, "mca_sharedfp_individual_file_open: Error during memory allocation\n");

        sh = NULL;
        err = OMPI_ERR_OUT_OF_RESOURCE;
        goto exit;
    }
    err = mca_common_ompio_file_open ( MPI_COMM_SELF,metadatafilename,
                                       MPI_MODE_RDWR | MPI_MODE_CREATE | MPI_MODE_DELETE_ON_CLOSE,
                                       &(MPI_INFO_NULL->super), metadatafilehandle, false);
    if ( OMPI_SUCCESS != err) {
       opal_output(ompi_sharedfp_base_framework.framework_output,
                   "mca_sharedfp_individual_file_open: Error during metadatafile file open. Continuing anyway. \n");
        free (sh);
        free (datafilename);
        mca_common_ompio_file_close ( datafilehandle);
        free (datafilehandle);
        free (metadatafilename);
        free (metadatafilehandle);

        // We reset the error code here to OMPI_SUCCESS since the individual component can act as
        // a dummy component, in case no sharedfp operations are used by the code. Invoking any write/read
        // operations will however lead to an error, since the sharedfp_data pointer will be NULL.
        sh = NULL;
        err = OMPI_SUCCESS;
        goto exit;
    }

    /*save the datafilehandle and metadatahandle in the sharedfp individual module data structure*/
    headnode = (mca_sharedfp_individual_header_record*)(sh->selected_module_data);
    if ( headnode) {
        headnode->datafilehandle     = datafilehandle;
        headnode->metadatafilehandle = metadatafilehandle;
        headnode->datafilename       = datafilename;
        headnode->metadatafilename   = metadatafilename;
    }


exit:
    /*save the sharedfp individual module data structure in the ompio filehandle structure*/
    fh->f_sharedfp_data = sh;

    return err;
}

int mca_sharedfp_individual_file_close (ompio_file_t *fh)
{
    mca_sharedfp_individual_header_record* headnode = NULL;
    struct mca_sharedfp_base_data_t *sh;
    int err = OMPI_SUCCESS;

    if ( NULL == fh->f_sharedfp_data ){
        return OMPI_SUCCESS;
    }
    sh = fh->f_sharedfp_data;

    /* Merge data from individual files to final output file */
    err = mca_sharedfp_individual_collaborate_data (sh, fh);

    headnode = (mca_sharedfp_individual_header_record*)(sh->selected_module_data);
    if (headnode)  {
        /*Close datafile*/
        if (headnode->datafilehandle)  {
            /*TODO: properly deal with returned error code*/
            err = mca_common_ompio_file_close(headnode->datafilehandle);
            /* NOTE: No need to manually delete the file,
	    ** the amode should have been set to delete on close
	    */
        }
        if(headnode->datafilename){
            free(headnode->datafilename);
        }

        /*Close metadatafile*/
        if (headnode->metadatafilehandle)  {
            /*TODO: properly deal with returned error code*/
            err = mca_common_ompio_file_close(headnode->metadatafilehandle);
            /* NOTE: No need to manually delete the file,
	    ** the amode should have been set to delete on close
	    */
        }
        if(headnode->metadatafilename){
            free(headnode->metadatafilename);
        }
    }

    /*free shared file pointer data struct*/
    free(sh);
    fh->f_sharedfp_data=NULL;

    return err;
}


mca_sharedfp_individual_header_record* mca_sharedfp_individual_insert_headnode ( void )
{
    mca_sharedfp_individual_header_record *headnode = NULL;
    if ( !headnode )  {
	/*Allocate a headnode*/
	headnode = (mca_sharedfp_individual_header_record*)malloc(sizeof(mca_sharedfp_individual_header_record));
	if (!headnode)
	    return NULL;
    }

    headnode->numofrecords = 0;			/* No records in the linked list */
    headnode->numofrecordsonfile = 0;		/* No records in the metadatafile for this file */

    headnode->datafile_offset = 0;
    headnode->metadatafile_offset = 0;

    headnode->metafile_start_offset = 0;
    headnode->datafile_start_offset = 0;

    headnode->metadatafilehandle = 0;
    headnode->datafilehandle     = 0;
    headnode->next   = NULL;

    return headnode;
}