/*
 * Copyright (c) 2002-2007, Communications and Remote Sensing Laboratory, Universite catholique de Louvain (UCL), Belgium
 * Copyright (c) 2002-2007, Professor Benoit Macq
 * Copyright (c) 2001-2003, David Janssens
 * Copyright (c) 2002-2003, Yannick Verschueren
 * Copyright (c) 2003-2007, Francois-Olivier Devaux and Antonin Descampe
 * Copyright (c) 2005, Herve Drolon, FreeImage Team
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS `AS IS'
 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 * POSSIBILITY OF SUCH DAMAGE.
 */

#include "opj_includes.h"

/* 
==========================================================
   Tag-tree coder interface
==========================================================
*/

opj_tgt_tree_t *tgt_create(int numleafsh, int numleafsv) {
	int nplh[32];
	int nplv[32];
	opj_tgt_node_t *node = NULL;
	opj_tgt_node_t *parentnode = NULL;
	opj_tgt_node_t *parentnode0 = NULL;
	opj_tgt_tree_t *tree = NULL;
	int i, j, k;
	int numlvls;
	int n;

	tree = (opj_tgt_tree_t *) opj_malloc(sizeof(opj_tgt_tree_t));
	if(!tree) return NULL;
	tree->numleafsh = numleafsh;
	tree->numleafsv = numleafsv;

	numlvls = 0;
	nplh[0] = numleafsh;
	nplv[0] = numleafsv;
	tree->numnodes = 0;
	do {
		n = nplh[numlvls] * nplv[numlvls];
		nplh[numlvls + 1] = (nplh[numlvls] + 1) / 2;
		nplv[numlvls + 1] = (nplv[numlvls] + 1) / 2;
		tree->numnodes += n;
		++numlvls;
	} while (n > 1);
	
	/* ADD */
	if (tree->numnodes == 0) {
		opj_free(tree);
		return NULL;
	}

	tree->nodes = (opj_tgt_node_t*) opj_calloc(tree->numnodes, sizeof(opj_tgt_node_t));
	if(!tree->nodes) {
		opj_free(tree);
		return NULL;
	}

	node = tree->nodes;
	parentnode = &tree->nodes[tree->numleafsh * tree->numleafsv];
	parentnode0 = parentnode;
	
	for (i = 0; i < numlvls - 1; ++i) {
		for (j = 0; j < nplv[i]; ++j) {
			k = nplh[i];
			while (--k >= 0) {
				node->parent = parentnode;
				++node;
				if (--k >= 0) {
					node->parent = parentnode;
					++node;
				}
				++parentnode;
			}
			if ((j & 1) || j == nplv[i] - 1) {
				parentnode0 = parentnode;
			} else {
				parentnode = parentnode0;
				parentnode0 += nplh[i];
			}
		}
	}
	node->parent = 0;
	
	tgt_reset(tree);
	
	return tree;
}

/**
 * Reinitialises a tag-tree from an exixting one.
 *
 * @param	p_tree				the tree to reinitialize.
 * @param	p_num_leafs_h		the width of the array of leafs of the tree
 * @param	p_num_leafs_v		the height of the array of leafs of the tree
 * @return	a new tag-tree if successful, NULL otherwise
*/
opj_tgt_tree_t *tgt_init(opj_tgt_tree_t * p_tree,OPJ_UINT32 p_num_leafs_h, OPJ_UINT32 p_num_leafs_v)
{
	OPJ_INT32 l_nplh[32];
	OPJ_INT32 l_nplv[32];
	opj_tgt_node_t *l_node = 00;
	opj_tgt_node_t *l_parent_node = 00;
	opj_tgt_node_t *l_parent_node0 = 00;
	OPJ_UINT32 i;
	OPJ_INT32 j,k;
	OPJ_UINT32 l_num_levels;
	OPJ_UINT32 n;
	OPJ_UINT32 l_node_size;

	if
		(! p_tree)
	{
		return 00;
	}
	if
		((p_tree->numleafsh != p_num_leafs_h) || (p_tree->numleafsv != p_num_leafs_v))
	{
		p_tree->numleafsh = p_num_leafs_h;
		p_tree->numleafsv = p_num_leafs_v;

		l_num_levels = 0;
		l_nplh[0] = p_num_leafs_h;
		l_nplv[0] = p_num_leafs_v;
		p_tree->numnodes = 0;
		do
		{
			n = l_nplh[l_num_levels] * l_nplv[l_num_levels];
			l_nplh[l_num_levels + 1] = (l_nplh[l_num_levels] + 1) / 2;
			l_nplv[l_num_levels + 1] = (l_nplv[l_num_levels] + 1) / 2;
			p_tree->numnodes += n;
			++l_num_levels;
		}
		while (n > 1);

		/* ADD */
		if
			(p_tree->numnodes == 0)
		{
			tgt_destroy(p_tree);
            return 00;
		}
		l_node_size = p_tree->numnodes * sizeof(opj_tgt_node_t);
		if
			(l_node_size > p_tree->nodes_size)
		{
			p_tree->nodes = (opj_tgt_node_t*) opj_realloc(p_tree->nodes, l_node_size);
			if
				(! p_tree->nodes)
			{
				tgt_destroy(p_tree);
				return 00;
			}
			memset(((char *) p_tree->nodes) + p_tree->nodes_size, 0 , l_node_size - p_tree->nodes_size);
			p_tree->nodes_size = l_node_size;
		}
		l_node = p_tree->nodes;
		l_parent_node = &p_tree->nodes[p_tree->numleafsh * p_tree->numleafsv];
		l_parent_node0 = l_parent_node;

		for
			(i = 0; i < l_num_levels - 1; ++i)
		{
			for
				(j = 0; j < l_nplv[i]; ++j)
			{
				k = l_nplh[i];
				while
					(--k >= 0)
				{
					l_node->parent = l_parent_node;
					++l_node;
					if (--k >= 0)
					{
						l_node->parent = l_parent_node;
						++l_node;
					}
					++l_parent_node;
				}
				if ((j & 1) || j == l_nplv[i] - 1)
				{
					l_parent_node0 = l_parent_node;
				}
				else
				{
					l_parent_node = l_parent_node0;
					l_parent_node0 += l_nplh[i];
				}
			}
		}
		l_node->parent = 0;
	}
	tgt_reset(p_tree);

	return p_tree;
}

void tgt_destroy(opj_tgt_tree_t *tree) {
	opj_free(tree->nodes);
	opj_free(tree);
}

void tgt_reset(opj_tgt_tree_t *tree) {
	int i;

	if (NULL == tree)
		return;
	
	for (i = 0; i < tree->numnodes; i++) {
		tree->nodes[i].value = 999;
		tree->nodes[i].low = 0;
		tree->nodes[i].known = 0;
	}
}

void tgt_setvalue(opj_tgt_tree_t *tree, int leafno, int value) {
	opj_tgt_node_t *node;
	node = &tree->nodes[leafno];
	while (node && node->value > value) {
		node->value = value;
		node = node->parent;
	}
}

void tgt_encode(opj_bio_t *bio, opj_tgt_tree_t *tree, int leafno, int threshold) {
	opj_tgt_node_t *stk[31];
	opj_tgt_node_t **stkptr;
	opj_tgt_node_t *node;
	int low;

	stkptr = stk;
	node = &tree->nodes[leafno];
	while (node->parent) {
		*stkptr++ = node;
		node = node->parent;
	}
	
	low = 0;
	for (;;) {
		if (low > node->low) {
			node->low = low;
		} else {
			low = node->low;
		}
		
		while (low < threshold) {
			if (low >= node->value) {
				if (!node->known) {
					bio_write(bio, 1, 1);
					node->known = 1;
				}
				break;
			}
			bio_write(bio, 0, 1);
			++low;
		}
		
		node->low = low;
		if (stkptr == stk)
			break;
		node = *--stkptr;
	}
}

int tgt_decode(opj_bio_t *bio, opj_tgt_tree_t *tree, int leafno, int threshold) {
	opj_tgt_node_t *stk[31];
	opj_tgt_node_t **stkptr;
	opj_tgt_node_t *node;
	int low;

	stkptr = stk;
	node = &tree->nodes[leafno];
	while (node->parent) {
		*stkptr++ = node;
		node = node->parent;
	}
	
	low = 0;
	for (;;) {
		if (low > node->low) {
			node->low = low;
		} else {
			low = node->low;
		}
		while (low < threshold && low < node->value) {
			if (bio_read(bio, 1)) {
				node->value = low;
			} else {
				++low;
			}
		}
		node->low = low;
		if (stkptr == stk) {
			break;
		}
		node = *--stkptr;
	}
	
	return (node->value < threshold) ? 1 : 0;
}