/*
 * The copyright in this software is being made available under the 2-clauses
 * BSD License, included below. This software may be subject to other third
 * party and contributor rights, including patent rights, and no such rights
 * are granted under this license.
 *
 * Copyright (c) 2002-2014, Universite catholique de Louvain (UCL), Belgium
 * Copyright (c) 2002-2014, Professor Benoit Macq
 * Copyright (c) 2001-2003, David Janssens
 * Copyright (c) 2002-2003, Yannick Verschueren
 * Copyright (c) 2003-2007, Francois-Olivier Devaux
 * Copyright (c) 2003-2014, 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;
}

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;
}
