void write_data_to_file(void* data, FILE * data_file, int last_written_byte_position, int bytes_number_to_write, const string& current_file, int id) {
    long int start_position = ftell(data_file);
    fwrite(((void*)((char*)data + last_written_byte_position)), 1, bytes_number_to_write, data_file);
    long int end_position = ftell(data_file);
    save_file_name_and_reading_positions(id, current_file, start_position, end_position);
}

bool write_data(int id, void* data, int current_data_size) {
    FILE * data_file = NULL;
    string current_file;
    int last_written_byte_position = 0;
    while (current_data_size != 0) {
        if (data_file == NULL) {
            current_file = get_new_file_path();
        }
        data_file = fopen(current_file.c_str(), "a+b");
        unsigned int file_free_space = get_file_free_space(current_file);
        if (file_free_space == 0) {
            current_file = get_new_file_path();
            data_file = fopen(current_file.c_str(), "a+b");
        }
        int bytes_number_to_write;
        if (current_data_size > file_free_space) {
            bytes_number_to_write = file_free_space;
            write_data_to_file(data, data_file, last_written_byte_position, bytes_number_to_write, current_file, id);
            last_written_byte_position += bytes_number_to_write;
        }
        else {
            bytes_number_to_write = current_data_size;
            write_data_to_file(data, data_file, last_written_byte_position, bytes_number_to_write, current_file, id);
        }
        current_data_size -= bytes_number_to_write;
        is_data_size_invalid(current_data_size);
        fclose(data_file);
        data_file = NULL;
    }
    return true;
}

#define CATCH_CONFIG_MAIN
#include "/Users/TwITe/Documents/Visual Studio 2017/Projects/Database/database_lib.h"
#include "/Users/TwITe/Documents/Visual Studio 2017/Projects/catch.hpp"

TEST_CASE("Data was succesfully writed to files", "[data_store]") {
    int arr[5]{ 0, 1, 2, 3, 4 };
    REQUIRE((write_data(1, arr, 20)) == true);
}