#include <sys/time.h>
#include <sys/mman.h>

#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <time.h>
#include <string.h>
#include <assert.h>
#include <limits.h>


#include "litmus.h"
#include "common.h"

extern int main_job(void);
static char* progname;

static void usage(char *error) {
	fprintf(stderr, "Error: %s\n", error);
	fprintf(stderr,
		"Usage:\n"
		"	rt_spin [COMMON-OPTS] WCET PERIOD DURATION\n"
		"	rt_spin [COMMON-OPTS] -f FILE [-o COLUMN] WCET PERIOD\n"
		"	rt_spin -l\n"
		"\n"
		"COMMON-OPTS = [-w] [-s SCALE]\n"
		"              [-p PARTITION/CLUSTER [-z CLUSTER SIZE]] [-c CLASS] [-m CRITICALITY LEVEL]\n"
		"              [-X LOCKING-PROTOCOL] [-L CRITICAL SECTION LENGTH] [-Q RESOURCE-ID]\n"
		"\n"
		"WCET and PERIOD are milliseconds, DURATION is seconds.\n"
		"CRITICAL SECTION LENGTH is in milliseconds.\n");
	exit(EXIT_FAILURE);
}

static int job(double exec_time, double program_end, int lock_od, double cs_length)
{
	if (wctime() > program_end)
		return 0;
	else {
		main_job();
		sleep_next_period();
		return 1;
	}
}

#define OPTSTR "p:c:wves:q:X:L:Q:vh:m:i:b:"
int main(int argc, char** argv)
{
	int ret;
	lt_t wcet;
	lt_t period;
	lt_t hyperperiod;
	lt_t budget;
	double wcet_ms, period_ms, hyperperiod_ms, budget_ms;
	unsigned int priority = LITMUS_NO_PRIORITY;
	int migrate = 0;
	int cluster = 0;
	int opt;
	int wait = 0;
	int want_enforcement = 0;
	double duration = 0, start = 0;
	double scale = 1.0;
	task_class_t class = RT_CLASS_HARD;
	struct rt_task param;
	struct mc2_task mc2_param;
	struct reservation_config config;
	int res_type = PERIODIC_POLLING;

	int verbose = 0;
	unsigned int job_no;

	/* locking */
	int lock_od = -1;
	int resource_id = 0;
	const char *lock_namespace = "./rtspin-locks";
	int protocol = -1;
	double cs_length = 1; /* millisecond */

	progname = argv[0];

	/* default for reservation */
	config.id = 0;
	config.priority = LITMUS_NO_PRIORITY; /* use EDF by default */
	config.cpu = -1;
	
	mc2_param.crit = CRIT_LEVEL_C;
	
	hyperperiod_ms = 1000;
	budget_ms = 10;
	
	while ((opt = getopt(argc, argv, OPTSTR)) != -1) {
		switch (opt) {
		case 'w':
			wait = 1;
			break;
		case 'p':
			cluster = atoi(optarg);
			migrate = 1;
			config.cpu = cluster;
			break;
		case 'q':
			priority = atoi(optarg);
			if (!litmus_is_valid_fixed_prio(priority))
				usage("Invalid priority.");
			break;
		case 'c':
			class = str2class(optarg);
			if (class == -1)
				usage("Unknown task class.");
			break;
		case 'e':
			want_enforcement = 1;
			break;
		case 's':
			scale = atof(optarg);
			break;
		case 'X':
			protocol = lock_protocol_for_name(optarg);
			if (protocol < 0)
				usage("Unknown locking protocol specified.");
			break;
		case 'L':
			cs_length = atof(optarg);
			if (cs_length <= 0)
				usage("Invalid critical section length.");
			break;
		case 'Q':
			resource_id = atoi(optarg);
			if (resource_id <= 0 && strcmp(optarg, "0"))
				usage("Invalid resource ID.");
			break;
		case 'v':
			verbose = 1;
			break;
		case 'm':
			mc2_param.crit = atoi(optarg);
			if (mc2_param.crit < CRIT_LEVEL_A || mc2_param.crit == NUM_CRIT_LEVELS) {
				usage("Invalid criticality level.");
			}
			res_type = PERIODIC_POLLING;
			break;
		case 'h':
			hyperperiod_ms = atof(optarg);
			break;
		case 'b':
			budget_ms = atof(optarg);
			break;
		case 'i':
			config.priority = atoi(optarg);
			break;
		case ':':
			usage("Argument missing.");
			break;
		case '?':
		default:
			usage("Bad argument.");
			break;
		}
	}

	if (mc2_param.crit > CRIT_LEVEL_A && config.priority != LITMUS_NO_PRIORITY)
		usage("Bad criticailty level or priority");

	if (argc - optind < 3)
		usage("Arguments missing.");

	wcet_ms   = atof(argv[optind + 0]);
	period_ms = atof(argv[optind + 1]);

	wcet   = ms2ns(wcet_ms);
	period = ms2ns(period_ms);
	budget = ms2ns(budget_ms);
	hyperperiod = ms2ns(hyperperiod_ms);
	
	if (wcet <= 0)
		usage("The worst-case execution time must be a "
				"positive number.");
	if (period <= 0)
		usage("The period must be a positive number.");
	if (wcet > period) {
		usage("The worst-case execution time must not "
				"exceed the period.");
	}

	duration  = atof(argv[optind + 2]);

	if (migrate) {
		ret = be_migrate_to_domain(cluster);
		if (ret < 0)
			bail_out("could not migrate to target partition or cluster.");
	}

	/* reservation config */
	config.id = gettid();
	
	if (hyperperiod%period != 0 ) {
		;//bail_out("hyperperiod must be multiple of period");
	}
	
	config.polling_params.budget = budget;
	config.polling_params.period = period;
	config.polling_params.offset = 0;
	config.polling_params.relative_deadline = 0;
	if (config.polling_params.budget > config.polling_params.period) {
		usage("The budget must not exceed the period.");
	}
	
	/* create a reservation */
	ret = reservation_create(res_type, &config);
	if (ret < 0) {
		bail_out("failed to create reservation.");
	}
	
	init_rt_task_param(&param);
	param.exec_cost = wcet;
	param.period = period;
	param.priority = priority;
	param.cls = class;
	param.release_policy = TASK_PERIODIC;
	param.budget_policy = (want_enforcement) ?
			PRECISE_ENFORCEMENT : NO_ENFORCEMENT;
	if (migrate) {
		param.cpu = gettid();
	}
	ret = set_rt_task_param(gettid(), &param);
	
	if (ret < 0)
		bail_out("could not setup rt task params");
	
	mc2_param.res_id = gettid();
	ret = set_mc2_task_param(gettid(), &mc2_param);
//printf("SET_MC2_TASK\n");
	if (ret < 0)
		bail_out("could not setup mc2 task params");

	init_litmus();
//printf("CALL\n");
	//set_page_color(config.cpu);
//printf("CALL\n");

//printf("INIT_LITMUS\n");
	start = wctime();
	ret = task_mode(LITMUS_RT_TASK);
//printf("TASK_MODE\n");
	if (ret != 0)
		bail_out("could not become RT task");

	if (protocol >= 0) {
		lock_od = litmus_open_lock(protocol, resource_id, lock_namespace, &cluster);
		if (lock_od < 0) {
			perror("litmus_open_lock");
			usage("Could not open lock.");
		}
	}


	if (wait) {
//printf("BEFORE WAIT\n");
		ret = wait_for_ts_release();
		if (ret != 0)
			bail_out("wait_for_ts_release()");
		start = wctime();
	}

	do {
		if (verbose) {
			get_job_no(&job_no);
			printf("rtspin/%d:%u @ %.4fms\n", gettid(),
				job_no, (wctime() - start) * 1000);
		}
	} while (job(wcet_ms * 0.001 * scale, start + duration,
		   lock_od, cs_length * 0.001));

printf("BEFORE BACK_TASK\n");
	ret = task_mode(BACKGROUND_TASK);
	if (ret != 0)
		bail_out("could not become regular task (huh?)");

	reservation_destroy(gettid(), config.cpu);
	
	return 0;
}