/*
 *  Copyright (c) 2012 The WebM project authors. All Rights Reserved.
 *
 *  Use of this source code is governed by a BSD-style license
 *  that can be found in the LICENSE file in the root of the source
 *  tree. An additional intellectual property rights grant can be found
 *  in the file PATENTS.  All contributing project authors may
 *  be found in the AUTHORS file in the root of the source tree.
 */

extern "C"
{
#include "vp8/encoder/boolhuff.h"
#include "vp8/decoder/dboolhuff.h"
}

#include <math.h>
#include <stddef.h>
#include <stdint.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/types.h>

#include "third_party/googletest/src/include/gtest/gtest.h"

typedef unsigned char uint8_t;

namespace
{
const int num_tests = 10;

class ACMRandom
{
public:
    ACMRandom(int seed) { Reset(seed);}

    void Reset(int seed) { srand(seed); }

    uint8_t Rand8(void) { return (rand() >> 8) & 0xff; }

    int PseudoUniform(int range) { return (rand() >> 8) % range; }

    int operator()(int n) { return PseudoUniform(n); }

    static int DeterministicSeed(void) { return 0xbaba; }
};
}

TEST(VP8, TestBitIO)
{
    ACMRandom rnd(ACMRandom::DeterministicSeed());
    for (int n = 0; n < num_tests; ++n)
    {
        for (int method = 0; method <= 7; ++method)
        {   // we generate various proba
            const int bits_to_test = 1000;

            uint8_t probas[bits_to_test];

            for (int i = 0; i < bits_to_test; ++i)
            {
                const int parity = i & 1;
                probas[i] =
                        (method == 0) ? 0 :
                        (method == 1) ? 255 :
                        (method == 2) ? 128 :
                        (method == 3) ? rnd.Rand8() :
                        (method == 4) ? (parity ? 0 : 255) :
                        // alternate between low and high proba:
                        (method == 5) ? (parity ? rnd(128) : 255 - rnd(128)) :
                        (method == 6) ?
                                (parity ? rnd(64) : 255 - rnd(64)) :
                                (parity ? rnd(32) : 255 - rnd(32));
            }
            for (int bit_method = 0; bit_method <= 3; ++bit_method)
            {
                const int random_seed = 6432;
                const int buffer_size = 10000;
                ACMRandom bit_rnd(random_seed);
                BOOL_CODER bw;
                uint8_t bw_buffer[buffer_size];
                vp8_start_encode(&bw, bw_buffer, bw_buffer + buffer_size);

                int bit = (bit_method == 0) ? 0 : (bit_method == 1) ? 1 : 0;
                for (int i = 0; i < bits_to_test; ++i)
                {
                    if (bit_method == 2)
                    {
                        bit = (i & 1);
                    }
                    else if (bit_method == 3)
                    {
                        bit = bit_rnd(2);
                    }
                    vp8_encode_bool(&bw, bit, (int) probas[i]);
                }

                vp8_stop_encode(&bw);

                BOOL_DECODER br;
                vp8dx_start_decode(&br, bw_buffer, buffer_size);
                bit_rnd.Reset(random_seed);
                for (int i = 0; i < bits_to_test; ++i)
                {
                    if (bit_method == 2)
                    {
                        bit = (i & 1);
                    }
                    else if (bit_method == 3)
                    {
                        bit = bit_rnd(2);
                    }
                    GTEST_ASSERT_EQ(vp8dx_decode_bool(&br, probas[i]), bit)
                      << "pos: "
                      << i << " / " << bits_to_test << " bit_method: "
                      << bit_method << " method: " << method;
                }

            }
        }
    }
}

int main(int argc, char **argv)
{
    ::testing::InitGoogleTest(&argc, argv);
    return RUN_ALL_TESTS();
}