/*
 * Copyright (C) 2011 Thomas Preud'homme <thomas.preud-homme@lip6.fr>
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to deal
 * in the Software without restriction, including without limitation the rights
 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 * copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in
 * all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
 * SOFTWARE.
 */

#include <sys/time.h>
#include <stdio.h>
#include <stdlib.h>
#include <limits.h>
#include <errno.h>


#define TIMEINF(t1, t2) ((t1.tv_sec < t2.tv_sec) || (t1.tv_usec < t2.tv_usec))
#define STRTOL_OVERFLOW(n) (((n == LONG_MIN) || (n == LONG_MAX)) && \
			    (errno == ERANGE))

long busy_usecs = 42;
long total_time_usecs = 42;
unsigned int seed;

void node(long entry_input, long *entry_output)
{
	//struct timeval cur_time, end_time;
	//long long usecs;
	long entry;
	static long inc = 0;

	entry = entry_input + inc++;
	/*gettimeofday(&cur_time, 0);
	usecs = busy_usecs + cur_time.tv_usec + cur_time.tv_sec * 1000000;
	end_time.tv_usec = usecs % 1000000;
	end_time.tv_sec = usecs / 1000000;
	while (TIMEINF(cur_time, end_time))
		gettimeofday(&cur_time, 0);*/
	*entry_output = entry;
}

int main(int argc, char *argv[])
{
	unsigned int i, j, seed;
	char **arg_p;
	long entries_1[8], entries_2[8], entries_3[8], entries_4[8], entries_5[8], entries_6[8];
	//long entries_7[8], entries_8[8], entries_9[8], entries_10[8];
	long entries_input[8], entries_output[8];
	long nb_entries, result;

	argc--;
	arg_p = argv;
	while(arg_p++, argc--)
	{
		if ((*arg_p)[0] == '-')
		{
			if ((!(*arg_p)[1]) || (*arg_p)[2])
			{
				printf("Unsupported option: %s\n", *arg_p);
				return -1;
			}
			switch((*arg_p)[1])
			{
				char *endptr;

				case 't':
					argc--, arg_p++;
					busy_usecs = strtol(*arg_p, &endptr,
							       10);
					if ((endptr == *arg_p) ||
					    (STRTOL_OVERFLOW(busy_usecs)))
					{
						fprintf(stderr, "Invalid time: "
								"%s\n", *arg_p);
						return -1;
					}
					break;

				case 'T':
					argc--, arg_p++;
					total_time_usecs = strtol(*arg_p,
								  &endptr, 10);
					if ((endptr == *arg_p) ||
					    (STRTOL_OVERFLOW(total_time_usecs)))
					{
						fprintf(stderr, "Invalid time: "
								"%s\n", *arg_p);
						return -1;
					}
					break;

				default:
					printf("Unsupported option: %s\n", *arg_p);
					return -1;
			}
		}
	}

	nb_entries = total_time_usecs / busy_usecs;
	printf("total_time_usecs: %ld, busy_usecs: %ld, nb_entries: %ld\n", total_time_usecs, busy_usecs, nb_entries);
	seed = 42;
	result = 0;

#pragma omp parallel num_threads (1) default (none) \
	shared (nb_entries, entries_output, seed, result) \
	private (entries_input, entries_1, entries_2, entries_3, entries_4, entries_5, entries_6, i, j)
	//private (entries_input, entries_1, entries_2, entries_3, entries_4, entries_5, entries_6, entries_7, entries_8, entries_9, entries_10, i, j)
	{
#pragma omp single
		{
			long random = rand_r(&seed);
			long inc;

			inc = random;
			for (i = 0; i < nb_entries; i += 64 / sizeof(long))
			{

#pragma omp task output (entries_input) shared (inc) private (j)
				{
					for (j = 0; j < 64 / sizeof(long); j++)
						entries_input[j] = inc++;
				}
#pragma omp task input (entries_input) output (entries_1) private (j)
				for (j = 0; j < 64 / sizeof(long); j++)
					node(entries_input[j], &entries_1[j]);


#pragma omp task input (entries_1) output (entries_2) private (j)
				for (j = 0; j < 64 / sizeof(long); j++)
					node(entries_1[j], &entries_2[j]);
#pragma omp task input (entries_2) output (entries_3) private (j)
				for (j = 0; j < 64 / sizeof(long); j++)
					node(entries_2[j], &entries_3[j]);


#pragma omp task input (entries_3) output (entries_4) private (j)
				for (j = 0; j < 64 / sizeof(long); j++)
					node(entries_3[j], &entries_4[j]);
#pragma omp task input (entries_4) output (entries_5) private (j)
				for (j = 0; j < 64 / sizeof(long); j++)
					node(entries_4[j], &entries_5[j]);


#pragma omp task input (entries_5) output (entries_6) private (j)
				for (j = 0; j < 64 / sizeof(long); j++)
					node(entries_5[j], &entries_6[j]);
#if 0
#pragma omp task input (entries_6) output (entries_7) private (j)
				for (j = 0; j < 64 / sizeof(long); j++)
					node(entries_6[j], &entries_7[j]);


#pragma omp task input (entries_7) output (entries_8) private (j)
				for (j = 0; j < 64 / sizeof(long); j++)
					node(entries_7[j], &entries_8[j]);
#pragma omp task input (entries_8) output (entries_9) private (j)
				for (j = 0; j < 64 / sizeof(long); j++)
					node(entries_8[j], &entries_9[j]);


#pragma omp task input (entries_9) output (entries_10) private (j)
				for (j = 0; j < 64 / sizeof(long); j++)
					node(entries_9[j], &entries_10[j]);
#endif
#pragma omp task input (entries_6) shared (result, entries_output) private (j)
				for (j = 0; j < 64 / sizeof(long); j++)
				{
					node(entries_6[j], &entries_output[j]);
					result += entries_output[j];
				}
			}
		}
	}
	printf("result: %ld\n", result);
	return 0;
}