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

static unsigned long vytvor_hash(const char* nazov){
    unsigned long h=0;int z;
    while((z=*nazov++))h=h*31+z;
    return h;
}

struct station* create_station(){
    struct station* stanica=malloc(sizeof(struct station));
    if(!stanica)return NULL;
    stanica->tracks=calloc(STATION_SIZE,sizeof(struct car*));
    if(!stanica->tracks){free(stanica);return NULL;}
    stanica->track_count=STATION_SIZE;
    return stanica;
}

void destroy_station(struct station* stanica){
    if(!stanica)return;
    for(int i=0;i<stanica->track_count;i++){
        struct car* a=stanica->tracks[i];
        while(a){
            struct car* d=a->next;
            free(a);
            a=d;
        }
    }
    free(stanica->tracks);
    free(stanica);
}

int select_track(struct station* stanica,const char* nazov){
    if(!stanica||!nazov)return 0;
    unsigned long h=vytvor_hash(nazov);
    return (int)(h%stanica->track_count);
}

void add_target_capacity(struct station* stanica,const char* nazov,int pocet){
    if(!stanica||!nazov)return;
    int cislo=select_track(stanica,nazov);
    struct car* a=stanica->tracks[cislo];
    struct car* p=NULL;
    while(a){
        if(strcmp(a->value,nazov)==0){
            a->capacity+=pocet;
            return;
        }
        p=a;a=a->next;
    }
    struct car* novy=malloc(sizeof(struct car));
    if(!novy)return;
    strncpy(novy->value,nazov,TARGET_SIZE-1);
    novy->value[TARGET_SIZE-1]='\0';
    novy->capacity=pocet;
    novy->next=NULL;
    if(p==NULL)stanica->tracks[cislo]=novy;
    else p->next=novy;
}

int get_target_capacity(struct station* stanica,const char* nazov){
    if(!stanica||!nazov)return 0;
    int cislo=select_track(stanica,nazov);
    struct car* a=stanica->tracks[cislo];
    while(a){
        if(strcmp(a->value,nazov)==0)return a->capacity;
        a=a->next;
    }
    return 0;
}

int count_targets(struct station* stanica){
    if(!stanica)return 0;
    int pocet=0;
    for(int i=0;i<stanica->track_count;i++){
        struct car* a=stanica->tracks[i];
        while(a){pocet++;a=a->next;}
    }
    return pocet;
}

int count_capacity(struct station* stanica){
    if(!stanica)return 0;
    int suma=0;
    for(int i=0;i<stanica->track_count;i++){
        struct car* a=stanica->tracks[i];
        while(a){suma+=a->capacity;a=a->next;}
    }
    return suma;
}