#include <iostream>
#include <fstream>
#include <cstring>
#include <unistd.h>
#include <signal.h>
#include <string>
#include <cstring>
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)
{
	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());
	//cout << pgid<< endl;
	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 search_start_position = atoi(argv[3]);
	int search_end_position = atoi(argv[4]);
	//TODO
	ifstream inputFile(file_to_search_in);
	//cout << file_to_search_in  <<"\n";
	//cout << pattern_to_search_for <<"\n";
	string pattern = pattern_to_search_for;
	//cout << pattern;
	int len = pattern.length();
		//cout << fork() << endl;
	if ( !inputFile.is_open()){
		cerr << "Error opening the file" << endl;
		return 1;
	}
	
	//string line;
	//cout << "File Content: " << endl;
	int i=search_start_position;
	char ch;
	string pat="";
	inputFile.seekg(search_start_position);
	while (inputFile.get(ch) and i<=search_end_position){
		i++;
		if(pat.length() < len){
			pat = pat + ch;
			continue;
		}
		pat.erase(0,1);
		pat = pat+ ch;
		//pid_t pid = fork();
		//cout <<pat<<endl;
		if (pat == pattern){
			cout<< "[" << getpid() <<"] found at " << i - len << endl;
			killpg(pgid,SIGTERM);
			return 0;
			//break;
		}
	}
		
	cout <<"[" <<getpid() <<"] didn't find\n";
	return 1;
}