#include <stdio.h>
#include <string.h>
#include <stdlib.h>
#include <unistd.h>
#include <sys/wait.h>

char **parse_cmdline(const char *cmdline);

int main()
{
    size_t size=0; // razmera na prochetenoto
    char *suffer = NULL;   // tuka she se zapishe tova koeto prochete getline
    while(1)
    {
        printf("$ ");

        ssize_t vladi = getline(&suffer,&size,stdin);//vrusta kolko e prochelo , - 1 pri EOF ili greshka

        if( feof(stdin) ) {break;}

        char** direction;  //tuka pazim kakvoot vurne parse_cmdline

        suffer[strlen(suffer)-1]='\0'; /// mahame noviq red koito getline procheti sushto osven tova koeto e napisano

        direction = parse_cmdline(suffer);

        pid_t pid = fork(); // prvai nov proces

        if(pid < 0)
        {
            perror("fork");
        }
        else if(pid == 0)
        {
            int execv_result = execv(direction[0], direction);// ako se izpulni zamenq koda na procesa sus tozi na koito execvame
            if(execv_result == -1)// ako ima greshka ne zamenq koda
            {
                perror(direction[0]);
                free(direction[0]);
                free(direction);
                free(suffer);
                exit(0);
            }
            exit(0);//nenuzen exit tui kato ne moze da bude dostignat. ako exec proraboti to koda she e zamenen a ako ne to exit po gore she se vikne predi tozi tuk
        }
        else
        {
            waitpid(pid, 0, 0);
        }
        free(direction[0]); // napraktika freevame char *array = malloc(size * sizeof(char)); ot parse_cmdline
        free(direction);

         if( feof(stdin) ) {break;}
    }
    free(suffer);
    return 0;
}

char **parse_cmdline(const char *cmdline)
{
    int size = strlen(cmdline);
    char *array = malloc(size * sizeof(char)); // trqq da e size + 1 shot strcpy slaga '\0' nakraq
    strcpy(array, cmdline);

    int argc = 0;
    char **array_of_strings = malloc(sizeof(char*));

    char *ptr = strtok(array, " ");

    while (ptr)
    {


        array_of_strings[argc] = ptr;


        ptr = strtok(NULL, " ");

        argc++;
        array_of_strings = realloc(array_of_strings, (argc+1) * sizeof(char*));// + 1 za posledniq element da e null
    }
    array_of_strings[argc] = NULL;// viz komentara po gore

    return array_of_strings;
}