#include <cstring>
#include <cstdlib>
#include <iostream>
#include <sstream>
#include <libgearman/gearman.h>
#include <libgearman/worker.h>

using namespace std;

void *fib_worker(gearman_job_st *job, void *cb_arg, size_t *result_size, gearman_return_t *ret_ptr);
long fib(long n);
static void usage(char *name);

int main(int argc, char *argv[])
{
	int c;
	char *host = "127.0.0.1";
	in_port_t port = 0;
	gearman_worker_st worker;

	while ((c = getopt(argc, argv, "h:p:")) != -1) {
		switch(c) {
			case 'h':
				host = optarg;
				break;
			case 'p':
				port = (in_port_t) atoi(optarg);
				break;
			default:
				usage(argv[0]);
				exit(1);
		}
	}

	if (argc != optind) {
		usage(argv[0]);
		exit(1);
	}

	gearman_worker_create(&worker);
	gearman_worker_add_server(&worker, host, port);
	gearman_worker_add_function(&worker, "fib", 10, fib_worker, NULL);
	while (1) {
		gearman_worker_work(&worker);
	}

	return 0;
}

void *fib_worker(gearman_job_st *job, void *cb_arg, size_t *result_size, gearman_return_t *ret_ptr) {
	char ch[256];
	ostringstream os;
	int size = gearman_job_workload_size(job);
	strncpy(ch, (char *) gearman_job_workload(job), size);
	ch[size] = 0;
	long n = atol(ch);
	os << fib(n);
	string s = os.str();
	//cout << ch << ": " << s << endl;
	*result_size = s.size();
	*ret_ptr = GEARMAN_SUCCESS;
	return strdup(s.c_str());
}

long fib(long n) {
    if (n < 2) {
		return 1;
    } else {
		return fib(n - 2) + fib(n - 1);
    }
}

static void usage(char *name) {
	cout << "Usage: " << name << " [-h <host>] [-p <port>] <string>" << endl;
	cout << "\t-h <host> - job server host" << endl;
	cout << "\t-p <port> - job server port" << endl;
}