#include <iostream>
#include <fstream>
#include <cstring>
#include <unistd.h>
#include <signal.h>
#include <chrono>

using namespace std;

void handler(int signo, siginfo_t *info, void *context)
{
	if(signo == SIGTERM)
	{
		cout <<"["<< getpid()<<"] "<<"received SIGTERM\n";
		exit(0);
	}
}

int main(int argc, char **argv)
{
	auto startmain = chrono::high_resolution_clock::now();
	struct sigaction sa;
	memset(&sa, 0, sizeof(struct sigaction));
	sa.sa_sigaction = &handler;
	if (sigaction(SIGTERM, &sa, NULL) == -1)
	{
		perror("sigaction");
		return EXIT_FAILURE;
	}
	
	pid_t pgid = getpgid(getpid());

	if(argc != 5)
	{
		cout <<"usage: ./partitioner.out <path-to-file> <pattern> <search-start-position> <search-end-position>\nprovided arguments:\n";
		for(int i = 0; i < argc; i++)
			cout << argv[i] << "\n";
		return -1;
	}
	
	char *file_to_search_in = argv[1];
	char *pattern_to_search_for = argv[2];
	int len = sizeof(pattern_to_search_for);
	int search_start_position = atoi(argv[3]);
	int search_end_position = atoi(argv[4]);
	
	int find = 0;
	pid_t pid = getpid();
	ifstream file(file_to_search_in, ios::binary);
	int len2 = search_end_position - search_start_position;
	string buffer;
	buffer.resize(len2);
	file.seekg(search_start_position);
	file.read(&buffer[0], len2);

	//TODO
	auto a = buffer.find(pattern_to_search_for);
	if(a != string::npos) {
		cout << "[" << pid << "]" << " found at" << " " << a + search_start_position << endl;
		killpg(pgid,SIGTERM);
	}
	else {
		 cout << "[" << pid << "]" << " didn't find\n";
	}

	auto endmain = std::chrono::high_resolution_clock::now();
	chrono::duration<double> mainduration = endmain - startmain;
	cout << mainduration.count() << endl;
	return 0;
}