#include "list_ops.h"
#include "test-framework/unity.h"
#include <stdlib.h>
#include <stdbool.h>
#include <string.h>

list_t *new_list(size_t length, list_element_t elements[]) {
    list_t *list = malloc(sizeof(list_t) + length * sizeof(list_element_t));
    list->length = length;
    if (!list) {
        return NULL; 
    }
    for (size_t i = 0; i < length; i++) {
        list->elements[i] = elements[i];
    }
    return list;
}

list_t *append_list(list_t *list1, list_t *list2)
{
    size_t length = list1->length + list2->length;
    list_t *list3 = new_list(list1->length + list2->length,list1->elements);
    list3->length = length;
    for (size_t i = list1->length; i < list3->length; i++)
        list3->elements[i] = list2->elements[i - list1->length];
    return list3;
}

list_t *filter_list(list_t *list, bool (*predicate)(list_element_t)) {
   list_element_t filter[list->length];
   size_t filter_length = 0;
   for(size_t i = 0; i < list->length;i++){
     if(predicate(list->elements[i])){
       filter[filter_length++] = list->elements[i];
   	}
   }
   list_t *result = new_list(filter_length,filter);
    if (result == NULL) {
        return NULL; 
    }
   for(size_t i = 0;i < list->length;i++)
   		result->elements[i] = filter[i];
   return result;
}

size_t length_list(list_t *list) {
    return list->length;
}

list_t *map_list(list_t *list, list_element_t (*mapper)(list_element_t)) {
    list_t *result = new_list(list->length, list->elements);
     if (result == NULL) {
        return NULL; 
    }
	for (size_t i = 0; i < list->length; i++) {
        result->elements[i] = mapper(list->elements[i]);
    }

    return result;
}



list_element_t foldl_list(list_t *list, list_element_t initial, list_element_t (*folder)(list_element_t, list_element_t)) {
    list_element_t result = initial;
    for (size_t i = 0; i < list->length; i++) {
        result = folder(result, list->elements[i]);
    }
    
    return result;
}

list_element_t foldr_list(list_t *list, list_element_t initial, list_element_t (*folder)(list_element_t, list_element_t)) {
    list_element_t result = initial;
    for (size_t i = list->length; i > 0; i--) {
        result = folder(list->elements[i - 1], result);
    }
    
    return result;
}

list_t *reverse_list(list_t *list) {
    list_t *list2 = malloc(list->length); 
     if (NULL == list2) {
        return NULL; 
    }
    for (size_t i = 0; i < list->length; i++) {
        list2->elements[i] = list->elements[list->length - i - 1];
    }

    return list2;
}

void delete_list(list_t *list) {
    if (list != NULL) {
        free(list);
    }
}