/*

 * Copyright © 2012 Siarhei Siamashka <siarhei.siamashka@gmail.com>

 *

 * Permission is hereby granted, free of charge, to any person obtaining a

 * copy of this software and associated documentation files (the "Software"),

 * to deal in the Software without restriction, including without limitation

 * the rights to use, copy, modify, merge, publish, distribute, sublicense,

 * and/or sell copies of the Software, and to permit persons to whom the

 * Software is furnished to do so, subject to the following conditions:

 *

 * The above copyright notice and this permission notice (including the next

 * paragraph) shall be included in all copies or substantial portions of the

 * Software.

 *

 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR

 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,

 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL

 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER

 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING

 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER

 * DEALINGS IN THE SOFTWARE.

 */

#include "utils.h"

#include <assert.h>

#include <stdlib.h>

#include <stdio.h>

#include <math.h>

#ifdef HAVE_FLOAT128

#define pixman_fixed_to_float128(x) (((__float128)(x)) / 65536.0Q)

typedef struct { __float128 v[3]; } pixman_vector_f128_t;

typedef struct { __float128 m[3][3]; } pixman_transform_f128_t;

pixman_bool_t

pixman_transform_point_f128 (const pixman_transform_f128_t *t,

                             const pixman_vector_f128_t    *v,

                             pixman_vector_f128_t          *result)

{

    int i;

    for (i = 0; i < 3; i++)

    {

        result->v[i] = t->m[i][0] * v->v[0] +

                       t->m[i][1] * v->v[1] +

                       t->m[i][2] * v->v[2];

    }

    if (result->v[2] != 0)

    {

        result->v[0] /= result->v[2];

        result->v[1] /= result->v[2];

        result->v[2] = 1;

        return TRUE;

    }

    else

    {

        return FALSE;

    }

}

pixman_bool_t does_it_fit_fixed_48_16 (__float128 x)

{

    if (x >= 65536.0Q * 65536.0Q * 32768.0Q)

        return FALSE;

    if (x <= -65536.0Q * 65536.0Q * 32768.0Q)

        return FALSE;

    return TRUE;

}

#endif

static inline uint32_t

byteswap32 (uint32_t x)

{

    return ((x & ((uint32_t)0xFF << 24)) >> 24) |

           ((x & ((uint32_t)0xFF << 16)) >>  8) |

           ((x & ((uint32_t)0xFF <<  8)) <<  8) |

           ((x & ((uint32_t)0xFF <<  0)) << 24);

}

static inline uint64_t

byteswap64 (uint64_t x)

{

    return ((x & ((uint64_t)0xFF << 56)) >> 56) |

           ((x & ((uint64_t)0xFF << 48)) >> 40) |

           ((x & ((uint64_t)0xFF << 40)) >> 24) |

           ((x & ((uint64_t)0xFF << 32)) >>  8) |

           ((x & ((uint64_t)0xFF << 24)) <<  8) |

           ((x & ((uint64_t)0xFF << 16)) << 24) |

           ((x & ((uint64_t)0xFF <<  8)) << 40) |

           ((x & ((uint64_t)0xFF <<  0)) << 56);

}

static void

byteswap_transform (pixman_transform_t *t)

{

    int i, j;

    if (is_little_endian ())

        return;

    for (i = 0; i < 3; i++)

        for (j = 0; j < 3; j++)

            t->matrix[i][j] = byteswap32 (t->matrix[i][j]);

}

static void

byteswap_vector_48_16 (pixman_vector_48_16_t *v)

{

    int i;

    if (is_little_endian ())

        return;

    for (i = 0; i < 3; i++)

        v->v[i] = byteswap64 (v->v[i]);

}

uint32_t

test_matrix (int testnum, int verbose)

{

    uint32_t crc32 = 0;

    int i, j, k;

    pixman_bool_t is_affine;

    prng_srand (testnum);

    for (i = 0; i < 100; i++)

    {

        pixman_bool_t           transform_ok;

        pixman_transform_t      ti;

        pixman_vector_48_16_t   vi, result_i;

#ifdef HAVE_FLOAT128

        pixman_transform_f128_t tf;

        pixman_vector_f128_t    vf, result_f;

#endif

        prng_randmemset (&ti, sizeof(ti), 0);

        prng_randmemset (&vi, sizeof(vi), 0);

        byteswap_transform (&ti);

        byteswap_vector_48_16 (&vi;;

        for (j = 0; j < 3; j++)

        {

            /* make sure that "vi" contains 31.16 fixed point data */

            vi.v[j] >>= 17;

            /* and apply random shift */

            if (prng_rand_n (3) == 0)

                vi.v[j] >>= prng_rand_n (46);

        }

        if (prng_rand_n (2))

        {

            /* random shift for the matrix */

            for (j = 0; j < 3; j++)

                for (k = 0; k < 3; k++)

                    ti.matrix[j][k] >>= prng_rand_n (30);

        }

        if (prng_rand_n (2))

        {

            /* affine matrix */

            ti.matrix[2][0] = 0;

            ti.matrix[2][1] = 0;

            ti.matrix[2][2] = pixman_fixed_1;

        }

        if (prng_rand_n (2))

        {

            /* cartesian coordinates */

            vi.v[2] = pixman_fixed_1;

        }

        is_affine = (ti.matrix[2][0] == 0 && ti.matrix[2][1] == 0 &&

                     ti.matrix[2][2] == pixman_fixed_1 &&

                     vi.v[2] == pixman_fixed_1);

        transform_ok = TRUE;

        if (is_affine && prng_rand_n (2))

            pixman_transform_point_31_16_affine (&ti, &vi, &result_i);

        else

            transform_ok = pixman_transform_point_31_16 (&ti, &vi, &result_i);

#ifdef HAVE_FLOAT128

        /* compare with a reference 128-bit floating point implementation */

        for (j = 0; j < 3; j++)

        {

            vf.v[j] = pixman_fixed_to_float128 (vi.v[j]);

            for (k = 0; k < 3; k++)

            {

                tf.m[j][k] = pixman_fixed_to_float128 (ti.matrix[j][k]);

            }

        }

        if (pixman_transform_point_f128 (&tf, &vf, &result_f))

        {

            if (transform_ok ||

                (does_it_fit_fixed_48_16 (result_f.v[0]) &&

                 does_it_fit_fixed_48_16 (result_f.v[1]) &&

                 does_it_fit_fixed_48_16 (result_f.v[2])))

            {

                for (j = 0; j < 3; j++)

                {

                    double diff = fabs (result_f.v[j] -

                                        pixman_fixed_to_float128 (result_i.v[j]));

                    if (is_affine && diff > (0.51 / 65536.0))

                    {

                        printf ("%d:%d: bad precision for affine (%.12f)\n",

                               testnum, i, diff);

                        abort ();

                    }

                    else if (diff > (0.71 / 65536.0))

                    {

                        printf ("%d:%d: bad precision for projective (%.12f)\n",

                               testnum, i, diff);

                        abort ();

                    }

                }

            }

        }

#endif

        byteswap_vector_48_16 (&result_i);

        crc32 = compute_crc32 (crc32, &result_i, sizeof (result_i));

    }

    return crc32;

}

int

main (int argc, const char *argv[])

{

    return fuzzer_test_main ("matrix", 20000,

			     0xBEBF98C3,

			     test_matrix, argc, argv);

}