#include "a_train.h"
#include <stdio.h>
#include <stdlib.h>
#include <string.h>

struct car* add_car(struct car* first,const char* target) {
    struct car* newcar = calloc(1,sizeof(struct car));
    strcpy(newcar->value, target);
     if (first == NULL) {
        return newcar;
    }
    struct car* this = first;  
    while (this->next != NULL) {  
        this = this->next;  
    }
    this->next = newcar;
    return first;
}

void print_train(struct car* first) {
    struct car* this = first;
    while (this != NULL) {
        printf("%s\n", this->value);
        this = this->next;
    }
}

void cancel_train(struct car* first) {
    struct car* this = first;
    while (this != NULL) {
        struct car* next_car = this->next;  
        free(this);                         
        this = next_car;                    
   }
}


struct car* clear_train(struct car* first, const char* name) {
    struct car* this = first;
    struct car* prev = NULL;

    while (this != NULL) {
        if (strcmp(this->value, name) == 0) {
            if (prev == NULL) {
                struct car* temp = this->next;
                free(this);
                return clear_train(temp, name);
            } else {
                prev->next = this->next;
                free(this);
                return first;
            }
        }
        prev = this;
        this = this->next;
    }
    return first;
}