/*
  Copyright 2011 David Robillard <http://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.
*/

#include "zix/sorted_array.h"

#include "zix/common.h"

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

// #define ZIX_SORTED_ARRAY_DUMP 1

struct ZixSortedArrayImpl {
	void*         array;
	ZixComparator cmp;
	void*         cmp_data;
	size_t        elem_size;
	size_t        num_elems;
	bool          allow_duplicates;
};

#ifdef ZIX_SORTED_ARRAY_DUMP
static void
zix_sorted_array_print(ZixSortedArray* a)
{
	for (size_t i = 0; i < a->num_elems; ++i) {
		printf(" %ld", *(intptr_t*)((char*)a->array + (i * a->elem_size)));
	}
	printf("\n");
}
#    define DUMP(a) zix_sorted_array_print(a)
#else
#    define DUMP(a)
#endif

ZixSortedArray*
zix_sorted_array_new(bool          allow_duplicates,
                     ZixComparator cmp,
                     void*         cmp_data,
                     size_t        elem_size)
{
	ZixSortedArray* a = (ZixSortedArray*)malloc(sizeof(ZixSortedArray));
	a->array            = NULL;
	a->cmp              = cmp;
	a->cmp_data         = cmp_data;
	a->elem_size        = elem_size;
	a->num_elems        = 0;
	a->allow_duplicates = allow_duplicates;
	return a;
}

void
zix_sorted_array_free(ZixSortedArray* a)
{
	free(a->array);
	free(a);
}

size_t
zix_sorted_array_size(const ZixSortedArray* a)
{
	return a->num_elems;
}

ZixStatus
zix_sorted_array_insert(ZixSortedArray*     a,
                        const void*         e,
                        ZixSortedArrayIter* ai)
{
	if (a->num_elems == 0) {
		assert(!a->array);
		a->array = malloc(a->elem_size);
		memcpy(a->array, e, a->elem_size);
		++a->num_elems;
		*ai = a->array;
		return ZIX_STATUS_SUCCESS;
	}

	zix_sorted_array_find(a, e, ai);
	assert(*ai);
	const size_t i = (size_t)((char*)*ai - (char*)a->array) / a->elem_size;

	a->array = realloc(a->array, ++a->num_elems * a->elem_size);
	memmove((char*)a->array + ((i + 1) * a->elem_size),
	        (char*)a->array + (i * a->elem_size),
	        (a->num_elems - i - 1) * a->elem_size);
	memcpy((char*)a->array + (i * a->elem_size),
	       e,
	       a->elem_size);

	*ai = (char*)a->array + (i * a->elem_size);
	DUMP(t);
	return ZIX_STATUS_SUCCESS;
}

ZixStatus
zix_sorted_array_remove(ZixSortedArray* a, ZixSortedArrayIter ai)
{
	const size_t i = (size_t)((char*)ai - (char*)a->array) / a->elem_size;
	memmove((char*)a->array + (i * a->elem_size),
	        (char*)a->array + ((i + 1) * a->elem_size),
	        (a->num_elems - i - 1) * a->elem_size);
	--a->num_elems;
	DUMP(a);
	return ZIX_STATUS_SUCCESS;
}

static inline void*
zix_sorted_array_index_unchecked(const ZixSortedArray* a, size_t index)
{
	return (char*)a->array + (a->elem_size * index);
}

void*
zix_sorted_array_index(const ZixSortedArray* a, size_t index)
{
	if (index >= a->num_elems) {
		return NULL;
	}

	return zix_sorted_array_index_unchecked(a, index);
}

ZixStatus
zix_sorted_array_find(const ZixSortedArray* a,
                      const void*           e,
                      ZixSortedArrayIter*   ai)
{
	intptr_t lower = 0;
	intptr_t upper = a->num_elems - 1;
	while (upper >= lower) {
		const intptr_t i      = lower + ((upper - lower) / 2);
		void* const    elem_i = zix_sorted_array_index_unchecked(a, i);
		const int      cmp    = a->cmp(elem_i, e, a->cmp_data);

		if (cmp == 0) {
			*ai = elem_i;
			return ZIX_STATUS_SUCCESS;
		}

		if (cmp > 0) {
			upper = i - 1;
		} else {
			lower = i + 1;
		}
	}

	*ai = zix_sorted_array_index_unchecked(a, lower);
	return ZIX_STATUS_NOT_FOUND;
}

void*
zix_sorted_array_get_data(ZixSortedArrayIter ai)
{
	return ai;
}

ZixSortedArrayIter
zix_sorted_array_begin(ZixSortedArray* a)
{
	return a->array;
}

ZixSortedArrayIter
zix_sorted_array_end(ZixSortedArray* a)
{
	return (char*)a->array + (a->elem_size * a->num_elems);
}

bool
zix_sorted_array_iter_is_end(ZixSortedArray* a, ZixSortedArrayIter i)
{
	return i != zix_sorted_array_end(a);
}

ZixSortedArrayIter
zix_sorted_array_iter_next(ZixSortedArray* a, ZixSortedArrayIter i)
{
	return (char*)i + a->elem_size;
}