/*
  Copyright 2011-2020 David Robillard <d@drobilla.net>

  Permission to use, copy, modify, and/or distribute this software for any
  purpose with or without fee is hereby granted, provided that the above
  copyright notice and this permission notice appear in all copies.

  THIS SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
  WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
  MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
  ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
  WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
  ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
  OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
*/

#ifndef ZIX_TREE_H
#define ZIX_TREE_H

#include "zix/allocator.h"
#include "zix/attributes.h"
#include "zix/common.h"

#include <stdbool.h>
#include <stddef.h>

#ifdef __cplusplus
extern "C" {
#endif

/**
   @addtogroup zix
   @{
   @name Tree
   @{
*/

/// A balanced binary search tree
typedef struct ZixTreeImpl ZixTree;

/// An iterator over a @ref ZixTree
typedef struct ZixTreeNodeImpl ZixTreeIter;

/// Create a new (empty) tree
ZIX_API
ZixTree* ZIX_ALLOCATED
zix_tree_new(const ZixAllocator* ZIX_NULLABLE allocator,
             bool                             allow_duplicates,
             ZixComparator ZIX_NONNULL        cmp,
             void* ZIX_NULLABLE               cmp_data,
             ZixDestroyFunc ZIX_NULLABLE      destroy,
             const void* ZIX_NULLABLE         destroy_user_data);

/// Free `t`
ZIX_API
void
zix_tree_free(ZixTree* ZIX_NULLABLE t);

/// Return the number of elements in `t`
ZIX_PURE_API
size_t
zix_tree_size(const ZixTree* ZIX_NONNULL t);

/// Insert the element `e` into `t` and point `ti` at the new element
ZIX_API
ZixStatus
zix_tree_insert(ZixTree* ZIX_NONNULL t,
                void* ZIX_NULLABLE   e,
                ZixTreeIter* ZIX_NULLABLE* ZIX_NULLABLE ti);

/// Remove the item pointed at by `ti` from `t`
ZIX_API
ZixStatus
zix_tree_remove(ZixTree* ZIX_NONNULL t, ZixTreeIter* ZIX_NONNULL ti);

/**
   Set `ti` to an element equal to `e` in `t`.

   If no such item exists, `ti` is set to NULL.
*/
ZIX_API
ZixStatus
zix_tree_find(const ZixTree* ZIX_NONNULL t,
              const void* ZIX_NULLABLE   e,
              ZixTreeIter* ZIX_NULLABLE* ZIX_NONNULL ti);

/// Return the data associated with the given tree item
ZIX_PURE_API
void* ZIX_NULLABLE
zix_tree_get(const ZixTreeIter* ZIX_NULLABLE ti);

/// Return an iterator to the first (smallest) element in `t`
ZIX_PURE_API
ZixTreeIter* ZIX_NULLABLE
zix_tree_begin(ZixTree* ZIX_NONNULL t);

/// Return an iterator the the element one past the last element in `t`
ZIX_CONST_API
ZixTreeIter* ZIX_NULLABLE
zix_tree_end(ZixTree* ZIX_NONNULL t);

/// Return true iff `i` is an iterator to the end of its tree
ZIX_CONST_API
bool
zix_tree_iter_is_end(const ZixTreeIter* ZIX_NULLABLE i);

/// Return an iterator to the last (largest) element in `t`
ZIX_PURE_API
ZixTreeIter* ZIX_NULLABLE
zix_tree_rbegin(ZixTree* ZIX_NONNULL t);

/// Return an iterator the the element one before the first element in `t`
ZIX_CONST_API
ZixTreeIter* ZIX_NULLABLE
zix_tree_rend(ZixTree* ZIX_NONNULL t);

/// Return true iff `i` is an iterator to the reverse end of its tree
ZIX_CONST_API
bool
zix_tree_iter_is_rend(const ZixTreeIter* ZIX_NULLABLE i);

/// Return an iterator that points to the element one past `i`
ZIX_PURE_API
ZixTreeIter* ZIX_NULLABLE
zix_tree_iter_next(ZixTreeIter* ZIX_NULLABLE i);

/// Return an iterator that points to the element one before `i`
ZIX_PURE_API
ZixTreeIter* ZIX_NULLABLE
zix_tree_iter_prev(ZixTreeIter* ZIX_NULLABLE i);

/**
   @}
   @}
*/

#ifdef __cplusplus
} /* extern "C" */
#endif

#endif /* ZIX_TREE_H */