#include "a_station.h"
#include <stdlib.h>
#include <string.h>

struct station* create_station(){
   struct station* station = (struct station*)calloc(1,sizeof(struct station));
   station->tracks = (struct car**)calloc(STATION_SIZE, sizeof(struct car*));
   station->track_count = STATION_SIZE;
   return station;
}

void destroy_station(struct station* station){
	if (station == NULL) return;

        for (int i = 0; i < station->track_count; i++) {
        struct car* current = station->tracks[i];

        
        while (current != NULL) {
            struct car* next = current->next;
            free(current);
            current = next;
        }
    }

    
    free(station->tracks);

    
    free(station);
}

int select_track(struct station* station, const char* target){
    	unsigned int hash = 0;

    // Jednoduché hashovanie: sčítame všetky znaky
    for (int i = 0; target[i] != '\0'; i++) {
        hash += (unsigned char)target[i];
    }

    // Prevedieme hash na index v poli
    return hash % station->track_count;
}

void add_target_capacity(struct station* station,const char* target, int capacity){
	int track = select_track(station, target);
	struct car* current = station->tracks[track];

	    // 1. Ak je spojkový zoznam prázdny
	if (current == NULL) {
		struct car* new_car = calloc(1, sizeof(struct car));
		strcpy(new_car->value, target);
		new_car->capacity = capacity;
		new_car->next = NULL;
		station->tracks[track] = new_car;
		return;
	    }

	    // 2. Prejdeme zoznam
	    struct car* prev = NULL;
	    while (current != NULL) {
		if (strcmp(current->value, target) == 0) {
		    current->capacity += capacity;  
		    return;
		}
		prev = current;
		current = current->next;
	    }

	    // 3. Ak záznam neexistuje → pridáme nový na koniec
	    struct car* new_car = calloc(1, sizeof(struct car));
	    strcpy(new_car->value, target);
	    new_car->capacity = capacity;
	    new_car->next = NULL;

	    prev->next = new_car;
}

int get_target_capacity(struct station* station,const char* target){
    int track = select_track(station, target);
    struct car* current = station->tracks[track];

    while (current != NULL) {
        if (strcmp(current->value, target) == 0) {
            return current->capacity;
        }
        current = current->next;
    }
    return 0;
}

int count_targets(struct station* station){
	int count = 0;

	for (int i = 0; i < station->track_count; i++) {
		struct car* current = station->tracks[i];
		while (current != NULL) {
	    		count++;
	    		current = current->next;
		}
	}

	return count;
}

int count_capacity(struct station* station){
	int total = 0;
	for (int i = 0; i < station->track_count; i++) {
		struct car* current = station->tracks[i];
		while (current != NULL) {
			total += current->capacity;
			current = current->next;
        }
    }

    return total;
}