#include "a_train.h"

struct car* add_car(struct car* first, const char* target) {
    struct car* newcar = malloc(sizeof(struct car));
    if (!newcar) return first;

    strncpy(newcar->value, target, SIZE - 1);
    newcar->value[SIZE - 1] = '\0';
    newcar->next = NULL;

    if (first == NULL) {
        return newcar;
    }

    struct car* last = first;
    while (last->next)
        last = last->next;

    last->next = newcar;
    return first;
}

void print_train(const struct car* first) {
    for (const struct car* c = first; c; c = c->next)
        printf("%s\n", c->value);
}

void cancel_train(struct car* first) {
    while (first) {
        struct car* tmp = first->next;
        free(first);
        first = tmp;
    }
}

struct car* clear_train(struct car* first, const char* target) {
    // Odstráni vozne zo začiatku
    while (first && strcmp(first->value, target) == 0) {
        struct car* tmp = first->next;
        free(first);
        first = tmp;
    }

    if (!first) return NULL;

    struct car* prev = first;
    while (prev->next) {
        if (strcmp(prev->next->value, target) == 0) {
            struct car* del = prev->next;
            prev->next = del->next;
            free(del);
        } else {
            prev = prev->next;
        }
    }
    return first;
}