//
// Author: David Muto
// https://gist.github.com/pseudomuto/6334796#file-list-c
//
//  Modified by:
//         Michael E. Tryby
//         US EPA ORD
//
// Accessed on: April 9, 2019
//


#include <stdlib.h>
#include <string.h>
#include <assert.h>

#include "list.h"


list_t *create_list(int elementSize, freeFunction freeFn)
{
	list_t *list;
	list = (list_t *)calloc(1, sizeof(list_t));

    assert(elementSize > 0);
    list->logicalLength = 0;
    list->elementSize = elementSize;
    list->head = list->tail = NULL;
	list->freeFn = freeFn;
	return list;
}

void delete_list(list_t *list)
{
    listNode *current;
    while(list->head != NULL) {
        current = list->head;
        list->head = current->next;

		if (list->freeFn) {
			list->freeFn(current->data);
		}

        free(current->data);
        free(current);
    }

	free(list);
}

void prepend_list(list_t *list, void *element)
{
    listNode *node = malloc(sizeof(listNode));
    node->data = malloc(list->elementSize);
    memcpy(node->data, element, list->elementSize);

    node->next = list->head;
    list->head = node;

    // first node?
    if(!list->tail) {
        list->tail = list->head;
    }

    list->logicalLength++;
}

void append_list(list_t *list, void *element)
{
    listNode *node = malloc(sizeof(listNode));
    node->data = malloc(list->elementSize);
    node->next = NULL;

    memcpy(node->data, element, list->elementSize);

    if(list->logicalLength == 0) {
        list->head = list->tail = node;
    } else {
        list->tail->next = node;
        list->tail = node;
    }

    list->logicalLength++;
}

void for_each_list(list_t *list, listIterator iterator)
{
    assert(iterator != NULL);

    listNode *node = list->head;
    bool result = true;
    while(node != NULL && result) {
        result = iterator(node->data);
        node = node->next;
    }
}

void head_list(list_t *list, void **element, bool removeFromList)
{
    assert(list->head != NULL);
    
	listNode *node = list->head;

	*element = (void *)malloc(list->elementSize);
    memcpy(*element, node->data, list->elementSize);

    if(removeFromList) {
        list->head = node->next;
        list->logicalLength--;

		if (list->freeFn) {
			list->freeFn(node->data);
		}

        free(node->data);
        free(node);
    }
}

void tail_list(list_t *list, void *element)
{
    assert(list->tail != NULL);
    listNode *node = list->tail;
    memcpy(element, node->data, list->elementSize);
}

int size_list(list_t *list)
{
    return list->logicalLength;
}