/* This is sample program for Ninf-G, calculate PI with object handle */
#include "grpc.h"

char *func_name = "pi_object/pi_trial";
char *config_file = "client.conf";

int
main(int argc, char *argv[])
{
    grpc_object_handle_t_np *handles;
    grpc_sessionid_t *ids = NULL;
    grpc_error_t result = GRPC_NO_ERROR;
    char **hosts = NULL;
    double pi;
    long *count = NULL;
    long times, sum;
    int n;
    int i, j;

    if (argc < 3){
        fprintf(stderr, "USAGE: %s TIMES HOSTNAME\n", argv[0]);
        fprintf(stderr, "USAGE: %s TIMES HOSTNAME1 HOSTNAME2...\n", argv[0]);
        exit(2);
    }

    n = argc - 2;
    hosts = (char **)malloc(sizeof(char *) * n);
    if (hosts == NULL) {
        fprintf(stderr, "malloc: Can't allocate the storage for hostname.\n");
        exit(2);
    }
    for (i = 2, j = 0; j < n; i++, j++) {
        hosts[j] = NULL;
        hosts[j] = strdup(argv[i]);
        if (*hosts == NULL) {
            fprintf(stderr,
                 "strdup: Can't allocate the storage for hostname.\n");
            exit(2);
        }
    }

    times = atol(argv[1]) / n;

    handles = (grpc_object_handle_t_np *)malloc(
        sizeof(grpc_object_handle_t_np) * n);
    if (handles == NULL) {
        fprintf(stderr, "malloc: Can't allocate the storage for handles.\n");
        exit(2);
    }

    count = (long *)malloc(sizeof(long) * n);
    if (count == NULL) {
        fprintf(stderr, "malloc: Can't allocate the storage.\n");
        exit(2);
    }

    ids = (grpc_sessionid_t *)malloc(sizeof(grpc_sessionid_t) * n);
    if (ids == NULL) {
        fprintf(stderr, "malloc: Can't allocate the storage.\n");
        exit(2);
    }

    /* Initialize */
    result = grpc_initialize(config_file);
    if (result != GRPC_NO_ERROR){
        fprintf(stderr, "grpc_initialize() error. (%s)\n",
            grpc_error_string(result));
        exit(2);
    }

    /* Initialize Object handles */
    for (i = 0; i < n; i++) {
        result = grpc_object_handle_init_np(&handles[i], hosts[i],
            func_name);
        if (result != GRPC_NO_ERROR) {
            fprintf(stderr, "grpc_object_handle_init_np() error. (%s)\n",
                grpc_error_string(result));
            exit(2);
        }      
    }

    /* Asynchronous call */
    for (i = 0; i < n; i++) {
        result = grpc_invoke_async_np(&handles[i], "pi_trial",
            &ids[i], i, times, &count[i]);
        if (result != GRPC_NO_ERROR){
            fprintf(stderr, "grpc_invoke_async_np() error. (%s)\n",
                grpc_error_string(result));
            exit(2);
        }
    }

    /* wait for session */
    result = grpc_wait_all();
    if (result != GRPC_NO_ERROR){
        fprintf(stderr, "grpc_wait_all() error. (%s)\n",
            grpc_error_string(result));
        exit(2);
    }

    /* Destruct Function handles */
    for (i = 0; i < n; i++) {
        result = grpc_object_handle_destruct_np(&handles[i]);
        if (result != GRPC_NO_ERROR) {
            fprintf(stderr, "grpc_object_handle_destruct_np() error. (%s)\n",
                grpc_error_string(result));
            exit(2);
        }
    }

    /* Compute and display pi. */
    for (i = 0, sum = 0; i < n; i++) {
        sum += count[i];
    }
    pi = 4.0 * (sum / ((double) times * n));
    printf("PI = %f\n", pi);

    /* Finalize */
    result = grpc_finalize();
    if (result != GRPC_NO_ERROR) {
        fprintf(stderr, "grpc_finalize() error. (%s)\n",
            grpc_error_string(result));
        exit(2);
    }

    for (i = 0; i < n; i++) {
        free(hosts[i]);
    }
    free(hosts);
    free(handles);
    free(count);
    free(ids);

    return 0;
}