#include <stdio.h>
#include <stdbool.h>
#include <string.h>
#include <stdlib.h>
#include <ctype.h>

#define truel true
#define fragments   0x01    // split into fragments with given size -s
#define parts       0x02    // split into given number of parts -n
#define error       0x00    // error

typedef struct
{
    char* inputFileName;
    char* outputFileTemplate;
    int commandCode;
    int parameter;
} inputStruct;

inputStruct parseInput(int argc, char *argv[]);
int stringToInt(char* str);

int main (int argc, char *argv[])
{
    argc = 6;
    argv[1] = "hey.txt";
    argv[2] = "-s";
    argv[3] = "1";
    argv[4] = "-b";
    argv[5] = "bubuka";

    FILE* fp;
    inputStruct input = parseInput(argc, argv);

    if(input.commandCode == error)
    {
        printf("Input error\n");
        return -99;
    }
    else if(input.commandCode == fragments)
    {
        fp = fopen(input.inputFileName, "rb");
        char box;
        int n=0,m=1;
        char* name = (char*)malloc(strlen(input.outputFileTemplate)+100);
        strcpy(name, input.outputFileTemplate);
        printf("%s", name);
        strcat(name, "_");
        strcat(name, (char*)m);
        strcat(name,".txt");
        FILE* nano = fopen(name,"wb");
        while((box=getc(fp))!=EOF)
        {
            putc(box,nano);
            n++;
            if (n == input.parameter)
            {
                fclose(nano);
                m++;
                n=0;
                //name = input.outputFileTemplate;
                strcpy(name, input.outputFileTemplate);
                strcat(name,"_");
                strcat(name, (char*)m);
                strcat(name,".txt");
                //name = name + '_'+ m + '.txt';
                nano = fopen(name,"wb");
            }
        }
        if (n!=0)
        {
            fclose(nano);
        }
    }
    else if(input.commandCode == parts)
    {

    }
    else
    {
        printf("Unknown parse error\n");
        return -98;
    }

    fclose(fp);

    return 0;
}

inputStruct parseInput(int argc, char *argv[])
{
    inputStruct input;

    input.commandCode = 0;
    input.inputFileName = '\0';
    input.outputFileTemplate = '\0';
    input.parameter = 0;

    if(argc != 6)
    {
        input.commandCode = error;
        return input;
    }

    // first argument
    input.inputFileName = argv[1];

    // second argument
    char* arg2 = argv[2];
    if(strlen(arg2) != 2 || arg2[0] != '-')
    {
        input.commandCode = error;
        return input;
    }
    else if(arg2[1] == 'b')
    {
        input.outputFileTemplate = argv[3];
    }
    else if(arg2[1] == 'n')
    {
        int parametr = stringToInt(argv[3]);

        if(parametr)
            input.commandCode = parts;
        else
            input.commandCode = error;

        input.parameter = parametr;
    }
    else if(arg2[1] == 's')
    {
        int parametr = stringToInt(argv[3]);

        if(parametr)
            input.commandCode = fragments;
        else
            input.commandCode = error;

        input.parameter = parametr;
    }
    else
    {
        input.commandCode = error;
        return input;
    }

    // fourth argument

    char* arg4 = argv[4];
    if(strlen(arg4) != 2 || arg2[0] != '-')
    {
        input.commandCode = error;
        return input;
    }
    else if(arg4[1] == 'b')
    {
        if(input.outputFileTemplate == '\0')
            input.outputFileTemplate = argv[5];
        else
            input.commandCode = error;
    }
    else if(arg4[1] == 'n')
    {
        int parametr = stringToInt(argv[5]);

        if(parametr == true)
        {
            if(input.commandCode == 0)
                input.commandCode = parts;
        }
        else
            input.commandCode = error;

        input.parameter = parametr;
    }
    else if(arg4[1] == 's')
    {
        int parametr = stringToInt(argv[5]);

        if(parametr == truel)
        {
            if(input.commandCode == 0)
                input.commandCode = fragments;
        }
        else
            input.commandCode = error;

        input.parameter = parametr;
    }
    else
    {
        input.commandCode = error;
        return input;
    }

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