/*
 * Copyright (C) 2013 Google Inc. All rights reserved.
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 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are
 * met:
 *
 *     * Redistributions of source code must retain the above copyright
 * notice, this list of conditions and the following disclaimer.
 *     * 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.
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 * contributors may be used to endorse or promote products derived from
 * this software without specific prior written permission.
 *
 * 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
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 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */

#include "config.h"

#include <algorithm>
#include <cstdlib>

#include "platform/SharedBuffer.h"
#include "platform/TestingPlatformSupport.h"
#include "public/platform/WebDiscardableMemory.h"

#include "wtf/ArrayBuffer.h"
#include "wtf/RefPtr.h"
#include "wtf/Vector.h"
#include <gtest/gtest.h>

using namespace WebCore;

namespace {

TEST(SharedBufferTest, getAsArrayBuffer)
{
    char testData0[] = "Hello";
    char testData1[] = "World";
    char testData2[] = "Goodbye";

    RefPtr<SharedBuffer> sharedBuffer = SharedBuffer::create(testData0, strlen(testData0));
    sharedBuffer->append(testData1, strlen(testData1));
    sharedBuffer->append(testData2, strlen(testData2));

    RefPtr<ArrayBuffer> arrayBuffer = sharedBuffer->getAsArrayBuffer();

    char expectedConcatenation[] = "HelloWorldGoodbye";
    ASSERT_EQ(strlen(expectedConcatenation), arrayBuffer->byteLength());
    EXPECT_EQ(0, memcmp(expectedConcatenation, arrayBuffer->data(), strlen(expectedConcatenation)));
}

TEST(SharedBufferTest, getAsArrayBufferLargeSegments)
{
    Vector<char> vector0(0x4000);
    for (size_t i = 0; i < vector0.size(); ++i)
        vector0[i] = 'a';
    Vector<char> vector1(0x4000);
    for (size_t i = 0; i < vector1.size(); ++i)
        vector1[i] = 'b';
    Vector<char> vector2(0x4000);
    for (size_t i = 0; i < vector2.size(); ++i)
        vector2[i] = 'c';

    RefPtr<SharedBuffer> sharedBuffer = SharedBuffer::adoptVector(vector0);
    sharedBuffer->append(vector1);
    sharedBuffer->append(vector2);

    RefPtr<ArrayBuffer> arrayBuffer = sharedBuffer->getAsArrayBuffer();

    ASSERT_EQ(0x4000U + 0x4000U + 0x4000U, arrayBuffer->byteLength());
    int position = 0;
    for (int i = 0; i < 0x4000; ++i) {
        EXPECT_EQ('a', static_cast<char*>(arrayBuffer->data())[position]);
        ++position;
    }
    for (int i = 0; i < 0x4000; ++i) {
        EXPECT_EQ('b', static_cast<char*>(arrayBuffer->data())[position]);
        ++position;
    }
    for (int i = 0; i < 0x4000; ++i) {
        EXPECT_EQ('c', static_cast<char*>(arrayBuffer->data())[position]);
        ++position;
    }
}

TEST(SharedBufferTest, copy)
{
    Vector<char> testData(10000);
    std::generate(testData.begin(), testData.end(), &std::rand);

    unsigned length = testData.size();
    RefPtr<SharedBuffer> sharedBuffer = SharedBuffer::create(testData.data(), length);
    sharedBuffer->append(testData.data(), length);
    sharedBuffer->append(testData.data(), length);
    sharedBuffer->append(testData.data(), length);
    // sharedBuffer must contain data more than segmentSize (= 0x1000) to check copy().
    ASSERT_EQ(length * 4, sharedBuffer->size());

    RefPtr<SharedBuffer> clone = sharedBuffer->copy();
    ASSERT_EQ(length * 4, clone->size());
    ASSERT_EQ(0, memcmp(clone->data(), sharedBuffer->data(), clone->size()));

    clone->append(testData.data(), length);
    ASSERT_EQ(length * 5, clone->size());
}

TEST(SharedBufferTest, constructorWithSizeOnly)
{
    unsigned length = 10000;
    RefPtr<SharedBuffer> sharedBuffer = SharedBuffer::create(length);
    ASSERT_EQ(length, sharedBuffer->size());

    // The internal flat buffer should have been resized to |length| therefore getSomeData() should
    // directly return the full size.
    const char* data;
    ASSERT_EQ(length, sharedBuffer->getSomeData(data, 0));
}

TEST(SharedBufferTest, createPurgeable)
{
    Vector<char> testData(30000);
    std::generate(testData.begin(), testData.end(), &std::rand);

    TestingPlatformSupport::Config config;
    config.hasDiscardableMemorySupport = true;
    TestingPlatformSupport platformWithDiscardableMemorySupport(config);

    unsigned length = testData.size();
    RefPtr<SharedBuffer> sharedBuffer = SharedBuffer::createPurgeable(testData.data(), length);
    ASSERT_EQ(length, sharedBuffer->size());
    // Merge the segments into a single vector.
    const char* data = sharedBuffer->data();
    ASSERT_EQ(0, memcmp(data, testData.data(), length));

    // Do another append + merge the segments again.
    size_t previousTestDataSize = testData.size();
    testData.resize(2 * previousTestDataSize);
    std::generate(testData.begin() + previousTestDataSize, testData.end(), &std::rand);
    sharedBuffer->append(testData.data() + previousTestDataSize, previousTestDataSize);
    ASSERT_EQ(0, memcmp(data, testData.data(), length));
}

} // namespace