#include <iostream>
#include <fstream>
#include <string>

//takes in an fstream, a filename, two ints
void temp(std::fstream &fs, const std::string &filename, int count)
{
    using namespace std;
    int start, delta;

    //input start
    cout << "Input the start point of deletion. Starts at 1, ends at " << count << endl;
    cin >> start;
    if(start < 1 || start > count) { cout << "You died" <<endl; return; }

    //input delta
    cout << "Input how many messages you want to delete from the start point;"
    << " Write 1 to delete only the one at the start; 0 to not delete anything; max value is " << count+1-start << endl;
    cin >> delta;
    if(delta < 0 || delta > count+1-start) { cout << "You died" << endl; return; }
    if(delta == 0) return;




    std::string fs_filename = filename + "_temp.txt"
    std::string line;
    while(getline(fs, line)) if(line.find('\r') != std::string::npos) line.erase(line.end()-1, line.end());
    fs.clear(); fs.seekg(0);



    if(!fs.is_open())
    {
        std::cout << "error" << std::endl;
        return;
    }

    auto print_ = [&fs]()
    {
        int counter = 0; fs.clear(); fs.seekg(0);

        std::string line;
        while(getline(fs, line)) std::cout << ++counter << ". "<< line << '\n';

        fs.clear(); fs.seekg(0);
    };

    //print_();

    //make a fstemp file
    std::fstream fstemp(fs_filename, std::fstream::out);
    int counter(0);



    fstemp.close(); fstemp.open(filename, std::fstream::in | std::fstream::out);

    while(getline(fs, line)) {
        if(++counter >= line_to_delete)
            fstemp << line << '\n';
    }

    fs.close(); fs.open(filename, std::fstream::out);

    while(getline(fstemp, line))
    {
        //std::cout << line;
        fs << line;
        //STILL couts nothing
    }
    //print_(); //prints nothing

    //test_temp.txt is empty after running it
    //test.txt has expected output
    std::remove(fs_filename.c_str());
    return;
}

int main()
{
    std::string filename = "test";
    filename += ".txt";
    std::fstream fs(filename, std::fstream::in | std::fstream::out);


    temp(fs, filename);
}