/*
 * (C) Copyright 2005- ECMWF.
 *
 * This software is licensed under the terms of the Apache Licence Version 2.0
 * which can be obtained at http://www.apache.org/licenses/LICENSE-2.0.
 *
 * In applying this licence, ECMWF does not waive the privileges and immunities granted to it by
 * virtue of its status as an intergovernmental organisation nor does it submit to any jurisdiction.
 */
/*
 * Test for ECC-604: GRIB decoding/encoding sequentially and parallel with POSIX threads
 */
#include <time.h>
#include <pthread.h>
#include <unistd.h>

#include "grib_api.h"

/* These are passed in via argv */
static size_t NUM_THREADS         = 0;
static size_t FILES_PER_ITERATION = 0;
static char* INPUT_FILE           = NULL;
int opt_dump                      = 0; /* If 1 then dump handle to /dev/null */
int opt_clone                     = 0; /* If 1 then clone source handle */
int opt_write                     = 0; /* If 1 write handle to file */

static int encode_values(grib_handle* h, char* output_file)
{
    double* values = NULL;
    long numberOfDataPoints = 0;
    GRIB_CHECK(grib_get_long(h, "numberOfDataPoints", &numberOfDataPoints), 0);
    size_t size = numberOfDataPoints;

    values = (double*)malloc(size * sizeof(double));
    for (size_t i = 0; i < size; ++i) {
        double v = i;
        if (i % size == 0) v = 0;
        values[i] = v;
    }
    GRIB_CHECK(grib_set_long(h, "bitsPerValue", 16), 0);
    GRIB_CHECK(grib_set_double_array(h, "values", values, size), 0);
    free(values);
    if (opt_dump) {
        FILE* devnull = fopen("/dev/null", "w");
        grib_dump_content(h, devnull, "wmo", 0, NULL);
    }
    return GRIB_SUCCESS;
}

void do_encode(void* data);

/* Structure for passing data to threads */
struct v
{
    size_t number;
    char* data;
};

void* runner(void* ptr); /* the thread */

int main(int argc, char** argv)
{
    size_t i;
    int thread_counter = 0;
    int parallel = 1, index = 0, c = 0;
    const char* prog = argv[0];
    char* mode;
    if (argc < 5 || argc > 7) {
        fprintf(stderr, "Usage:\n\t%s [options] seq sample numRuns numIter\nOr\n\t%s [options] par sample numThreads numIter\n", prog, prog);
        fprintf(stderr, "Options:\n\t-d: do a dump\n\t-c: clone\n");
        return 1;
    }

    while ((c = getopt(argc, argv, "dcw")) != -1) {
        switch (c) {
            case 'd':
                opt_dump = 1;
                break;
            case 'c':
                opt_clone = 1;
                break;
            case 'w':
                opt_write = 1;
                break;
        }
    }
    index               = optind;
    mode                = argv[index];
    INPUT_FILE          = argv[index + 1]; /* Has to be the name of a sample file (without tmpl extension) */
    NUM_THREADS         = atol(argv[index + 2]);
    FILES_PER_ITERATION = atol(argv[index + 3]);

    if (strcmp(mode, "seq") == 0) {
        parallel = 0;
    }
    if (parallel) {
        printf("Running parallel in %zu threads. %zu iterations (prod=%zu)\n", NUM_THREADS, FILES_PER_ITERATION, NUM_THREADS * FILES_PER_ITERATION);
        printf("Options: dump=%d, clone=%d, write=%d\n", opt_dump, opt_clone, opt_write);
    }
    else {
        printf("Running sequentially in %zu runs. %zu iterations\n", NUM_THREADS, FILES_PER_ITERATION);
    }

    {
        pthread_t* workers = (pthread_t*)malloc(NUM_THREADS * sizeof(pthread_t));
        for (i = 0; i < NUM_THREADS; i++) {
            struct v* data = (struct v*)malloc(sizeof(struct v));
            data->number   = i;
            data->data     = NULL;

            if (parallel) {
                /* Now we will create the thread passing it data as an argument */
                pthread_create(&workers[thread_counter], NULL, runner, data);
                thread_counter++;
            }
            else {
                do_encode(data);
            }
        }

        if (parallel) {
            for (i = 0; i < NUM_THREADS; i++) {
                pthread_join(workers[i], NULL);
            }
        }
        free(workers);
    }

    return 0;
}

void* runner(void* ptr)
{
    do_encode(ptr);
    free(ptr);
    pthread_exit(0);
}

void do_encode(void* ptr)
{
    /* Cast argument to struct v pointer */
    struct v* data = (struct v*)ptr;
    size_t i;
    char output_file[50];
    time_t ltime;
    struct tm result;
    char stime[32];
    grib_handle* hs = NULL;

    hs = grib_handle_new_from_samples(0, INPUT_FILE);

    for (i = 0; i < FILES_PER_ITERATION; i++) {
        grib_handle* h = NULL;
        if (opt_clone) {
            h = grib_handle_clone(hs);
        } else {
            h = hs;
        }
        if (opt_write) {
            snprintf(output_file, 50, "output/output_file_%zu-%zu.grib", data->number, i);
            encode_values(h, output_file);
        }
        else {
            encode_values(h, NULL);
        }
        if (opt_clone)
            grib_handle_delete(h);
    }

    ltime = time(NULL);
    localtime_r(&ltime, &result);
    strftime(stime, 32, "%H:%M:%S", &result); /* Try to get milliseconds here too*/
    /* asctime_r(&result, stime); */

    printf("%s: Worker %zu finished.\n", stime, data->number);
    grib_handle_delete(hs);
}