/*
 *   Sweet is a small library for basic math and small matrix operations.
 *   Copyright 2014 Luc Girod.
 *
 * This library is free software: you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation, either
 * version 3 of the License, or (at your option) any later version.
 *
 * This library is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with this library.  If not, see <http://www.gnu.org/licenses/>.
 */

#include <stdlib.h>
#include "sweet_matrix_stack.h"

matrix_stack2
sweet_matrix_stack2_new ()
{
    matrix_stack2 m;
    m.position = 0;
    m.matrix[0] = sweet_matrix_identity2 ();
    return m; 
}

matrix_stack3
sweet_matrix_stack3_new ()
{
    matrix_stack3 m;
    m.position = 0;
    m.matrix[0] = sweet_matrix_identity3 ();
    return m; 
}

matrix_stack4
sweet_matrix_stack4_new ()
{
    matrix_stack4 m;
    m.position = 0;
    m.matrix[0] = sweet_matrix_identity4 ();
    return m; 
}

int
sweet_matrix_stack2_push (matrix_stack2 * ms)
{
    if (ms->position >= SWEET_MATRIX_STACK_SIZE) { return 1; }

    ms->matrix[ms->position + 1] = ms->matrix[ms->position];
    ms->position++;
    return 0;
}

int
sweet_matrix_stack3_push (matrix_stack3 * ms)
{
    if (ms->position >= SWEET_MATRIX_STACK_SIZE) { return 1; }

    ms->matrix[ms->position + 1] = ms->matrix[ms->position];
    ms->position++;
    return 0;
}

int
sweet_matrix_stack4_push (matrix_stack4 * ms)
{
    if (ms->position >= SWEET_MATRIX_STACK_SIZE) { return 1; }

    ms->matrix[ms->position + 1] = ms->matrix[ms->position];
    ms->position = ms->position++;
    return 0;
}


int
sweet_matrix_stack2_pop (matrix_stack2 * ms)
{
    if (ms->position <= 0) { return 1; }

    ms->position--;
    return 0;
}

int
sweet_matrix_stack3_pop (matrix_stack3 * ms)
{
    if (ms->position <= 0) { return 1; }

    ms->position--;
    return 0;
}

int
sweet_matrix_stack4_pop (matrix_stack4 * ms)
{
    if (ms->position <= 0) { return 1; }

    ms->position--;
    return 0;
}

void
sweet_matrix_stack2_mult (matrix_stack2 * ms, mat2 * m)
{
    sweet_matrix_product2 (ms->matrix + ms->position,
                           ms->matrix + ms->position, m);
}

void
sweet_matrix_stack3_mult (matrix_stack3 * ms, mat3 * m)
{
    sweet_matrix_product3 (ms->matrix + ms->position,
                           ms->matrix + ms->position, m);
}

void
sweet_matrix_stack4_mult (matrix_stack4 * ms, mat4 * m)
{
    sweet_matrix_product4 (ms->matrix + ms->position,
                           ms->matrix + ms->position, m);
}

void
sweet_matrix_stack2_identity (matrix_stack2 * ms)
{
    ms->matrix[ms->position] = sweet_matrix_identity2 ();
}

void
sweet_matrix_stack3_identity (matrix_stack3 * ms)
{
    ms->matrix[ms->position] = sweet_matrix_identity3 ();
}

void
sweet_matrix_stack4_identity (matrix_stack4 * ms)
{
    ms->matrix[ms->position] = sweet_matrix_identity4 ();
}

void
sweet_matrix_stack2_set (matrix_stack2 * ms, mat2 * m)
{
    ms->matrix[ms->position] = *m;
}

void
sweet_matrix_stack3_set (matrix_stack3 * ms, mat3 * m)
{
    ms->matrix[ms->position] = *m;
}

void
sweet_matrix_stack4_set (matrix_stack4 * ms, mat4 * m)
{
    ms->matrix[ms->position] = *m;
}

mat2 *
sweet_matrix_stack2_get_matrix_pointer (matrix_stack2 * ms)
{
    return (ms->matrix + ms->position);
}

mat3 *
sweet_matrix_stack3_get_matrix_pointer (matrix_stack3 * ms)
{
    return (ms->matrix + ms->position);
}

mat4 *
sweet_matrix_stack4_get_matrix_pointer (matrix_stack4 * ms)
{
    return (ms->matrix + ms->position);
}
    
mat2
sweet_matrix_stack2_get_matrix (matrix_stack2 * ms)
{
    return ms->matrix[ms->position];
}

mat3
sweet_matrix_stack3_get_matrix (matrix_stack3 * ms)
{
    return ms->matrix[ms->position];
}

mat4
sweet_matrix_stack4_get_matrix (matrix_stack4 * ms)
{
    return ms->matrix[ms->position];
}