#include "cn-cbor/cn-cbor.h"
#include <stdlib.h>

#define INIT_CB(v) \
  if (errp) {errp->err = CN_CBOR_NO_ERROR;} \
  (v) = CN_CALLOC_CONTEXT(); \
  if (!(v)) { if (errp) {errp->err = CN_CBOR_ERR_OUT_OF_MEMORY;} return false; }

#define CBOR_CONTEXT_PARAM , context

#define CN_CALLOC(ctx) ((ctx) && (ctx)->calloc_func) ? \
    (ctx)->calloc_func(1, sizeof(cn_cbor), (ctx)->context) : \
    calloc(1, sizeof(cn_cbor));

#define CN_CALLOC_CONTEXT() CN_CALLOC(context)


/***
* Replace the i-th element in the array.
* Extend the array if necessary so it has enough elements.
*
* @param[in]    cn_cbor *		Array to use
* @param[in]	const cn_cbor *	New item to be placed in the array
* @param[in]	int				Zero based index to be used
* @param[in]	context	*		Context based allocation structure
* @param[in,out] cn_cbor_errback * CBOR error return on failure
* returns	    bool			Did we succeed?
*/

bool cn_cbor_array_replace(cn_cbor * cb_array, cn_cbor * cb_value, int index, CBOR_CONTEXT_COMMA cn_cbor_errback *errp)
{
	int i;
	cn_cbor * cb_temp;
	cn_cbor * cb_temp2;

	if (!cb_array || !cb_value || cb_array->type != CN_CBOR_ARRAY) {
		if (errp != NULL) errp->err = CN_CBOR_ERR_INVALID_PARAMETER;
		return false;
	}

	if (index == 0) {
		if (cb_array->length > 0) {
			cb_temp = cb_array->first_child;

			cb_value->parent = cb_array;
			cb_value->next = cb_temp->next;
			if (cb_array->last_child == cb_temp) {
				cb_array->last_child = cb_value;
			}
			cb_array->first_child = cb_value;
			cb_temp->parent = NULL;
			cb_temp->next = NULL;
			cn_cbor_free(cb_temp CBOR_CONTEXT_PARAM);
			return true;
		}
		return cn_cbor_array_append(cb_array, cb_value, errp);
	}

	if (cb_array->first_child == NULL) {
		INIT_CB(cb_temp2);
		cb_array->first_child = cb_array->last_child = cb_temp2;
		cb_temp2->parent = cb_array;
		cb_array->length = 1;
		cb_temp2->type = CN_CBOR_INVALID;
	}

	cb_temp = cb_array->first_child;
	for (i = 1; i < index; i++) {
		if (cb_temp->next == NULL) {
			INIT_CB(cb_temp2);
			cb_temp2->type = CN_CBOR_INVALID;
			cb_temp->next = cb_temp2;
			cb_temp2->parent = cb_array;
			cb_array->last_child = cb_temp2;
			cb_array->length += 1;
		}

		cb_temp = cb_temp->next;
	}

	if (cb_temp->next == NULL) {
		cb_temp->next = cb_value;
		cb_value->parent = cb_array;
		cb_array->last_child = cb_value;
		cb_array->length += 1;
		return true;
	}

	cb_temp2 = cb_temp->next;
	cb_value->next = cb_temp2->next;
	cb_temp->next = cb_value;
	cb_value->parent = cb_array;
	if (cb_array->last_child == cb_temp2) {
		cb_array->last_child = cb_value;
	}

	cb_temp2->next = NULL;
	cb_temp2->parent = NULL;
	cn_cbor_free(cb_temp2 CBOR_CONTEXT_PARAM);

	return true;
}