/*
 * This file Copyright (C) 2007-2014 Mnemosyne LLC
 *
 * It may be used under the GNU GPL versions 2 or 3
 * or any future license endorsed by Mnemosyne LLC.
 *
 */

#pragma once

#ifndef __TRANSMISSION__
#error only libtransmission should #include this header.
#endif

/**
 * @addtogroup utils Utilities
 * @{
 */

#include "transmission.h" /* inline */

/** @brief simple list structure similar to glib's GList */
typedef struct tr_list
{
    void* data;
    struct tr_list* next;
    struct tr_list* prev;
}
tr_list;

typedef int (* TrListCompareFunc)(void const* a, void const* b);
typedef void (* TrListForeachFunc)(void*);

/**
 * @brief return the number of items in the list
 * @return the number of items in the list
 */
int tr_list_size(tr_list const* list);

/**
 * @brief free the specified list and set its pointer to NULL
 * @param list pointer to the list to be freed
 * @param func optional function to invoke on each item in the list
 */
void tr_list_free(tr_list** list, TrListForeachFunc data_free_func);

/**
 * @brief append an item to the specified list
 * @param list pointer to the list
 * @param item the item to append
 */
void tr_list_append(tr_list** list, void* data);

/**
 * @brief prepend an item to the specified list
 * @param list pointer to the list
 * @param item the item to prepend
 */
void tr_list_prepend(tr_list** list, void* data);

/**
 * @brief remove the next item in the list
 * @return the next item in the list, or NULL if the list is empty
 * @param list pointer to the list
 */
void* tr_list_pop_front(tr_list** list);

/**
 * @brief remove the list's node that contains the specified data pointer
 * @param list pointer to the list
 * @param data data to remove
 * @return the removed data pointer, or NULL if no match was found
 */
void* tr_list_remove_data(tr_list** list, void const* data);

/**
 * @brief remove the list's node that compares equal to "b" when compared with "compare_func"
 * @param list pointer to the list
 * @param b the comparison key
 * @param compare_func the comparison function. The arguments passed to it will be the list's pointers and the comparison key "b"
 * @return the removed data pointer, or NULL if no match was found
 */
void* tr_list_remove(tr_list** list, void const* b, TrListCompareFunc compare_func);

/**
 * @brief find the list node whose data that compares equal to "b" when compared with "compare_func"
 * @param list pointer to the list
 * @param b the comparison key
 * @param compare_func the comparison function. The arguments passed to it will be the list's pointers and the comparison key "b"
 * @return the matching list node, or NULL if not match was found
 */
tr_list* tr_list_find(tr_list* list, void const* b, TrListCompareFunc compare_func);

/**
 * @brief Insert in an ordered list
 * @param list pointer to the list
 * @param item the item to be inserted
 * @param compare the comparison function.
 */
void tr_list_insert_sorted(tr_list** list, void* data, TrListCompareFunc compare);

/* @} */