/*
 * Copyright 2013 Google Inc.
 *
 * Use of this source code is governed by a BSD-style license that can be
 * found in the LICENSE file.
 */

#include "include/core/SkAnnotation.h"
#include "include/core/SkBitmap.h"
#include "include/core/SkBlendMode.h"
#include "include/core/SkCanvas.h"
#include "include/core/SkColor.h"
#include "include/core/SkColorFilter.h"
#include "include/core/SkData.h"
#include "include/core/SkDataTable.h"
#include "include/core/SkFont.h"
#include "include/core/SkFontArguments.h"
#include "include/core/SkFontMetrics.h"
#include "include/core/SkFontMgr.h"
#include "include/core/SkFontStyle.h"
#include "include/core/SkImage.h"
#include "include/core/SkImageFilter.h"
#include "include/core/SkImageInfo.h"
#include "include/core/SkMatrix.h"
#include "include/core/SkPaint.h"
#include "include/core/SkPath.h"
#include "include/core/SkPathEffect.h"
#include "include/core/SkPicture.h"
#include "include/core/SkPictureRecorder.h"
#include "include/core/SkPoint.h"
#include "include/core/SkPoint3.h"
#include "include/core/SkRRect.h"
#include "include/core/SkRect.h"
#include "include/core/SkRefCnt.h"
#include "include/core/SkRegion.h"
#include "include/core/SkSamplingOptions.h"
#include "include/core/SkScalar.h"
#include "include/core/SkSerialProcs.h"
#include "include/core/SkStream.h"
#include "include/core/SkString.h"
#include "include/core/SkSurface.h"
#include "include/core/SkTextBlob.h"
#include "include/core/SkTypeface.h"
#include "include/core/SkTypes.h"
#include "include/effects/SkDashPathEffect.h"
#include "include/effects/SkImageFilters.h"
#include "include/encode/SkPngEncoder.h"
#include "include/private/base/SkAlign.h"
#include "include/private/base/SkMalloc.h"
#include "include/private/base/SkTemplates.h"
#include "src/base/SkAutoMalloc.h"
#include "src/core/SkAnnotationKeys.h"
#include "src/core/SkImageFilter_Base.h"
#include "src/core/SkPicturePriv.h"
#include "src/core/SkReadBuffer.h"
#include "src/core/SkWriteBuffer.h"
#include "src/effects/colorfilters/SkColorFilterBase.h"
#include "tests/Test.h"
#include "tools/Resources.h"
#include "tools/ToolUtils.h"

#include <algorithm>
#include <array>
#include <cstdint>
#include <cstring>
#include <memory>
#include <utility>

using namespace skia_private;

static const uint32_t kArraySize = 64;
static const int kBitmapSize = 256;

class SerializationTest {
public:

template<typename T>
static void TestAlignment(T* testObj, skiatest::Reporter* reporter) {
    // Test memory read/write functions directly
    unsigned char dataWritten[1024];
    size_t bytesWrittenToMemory = testObj->writeToMemory(dataWritten);
    REPORTER_ASSERT(reporter, SkAlign4(bytesWrittenToMemory) == bytesWrittenToMemory);
    size_t bytesReadFromMemory = testObj->readFromMemory(dataWritten, bytesWrittenToMemory);
    REPORTER_ASSERT(reporter, SkAlign4(bytesReadFromMemory) == bytesReadFromMemory);
}
};

template<typename T> struct SerializationUtils {
    // Generic case for flattenables
    static void Write(SkWriteBuffer& writer, const T* flattenable) {
        writer.writeFlattenable(flattenable);
    }
    static void Read(SkReadBuffer& reader, T** flattenable) {
        *flattenable = (T*)reader.readFlattenable(T::GetFlattenableType());
    }
};

template<> struct SerializationUtils<SkMatrix> {
    static void Write(SkWriteBuffer& writer, const SkMatrix* matrix) {
        writer.writeMatrix(*matrix);
    }
    static void Read(SkReadBuffer& reader, SkMatrix* matrix) {
        reader.readMatrix(matrix);
    }
};

template<> struct SerializationUtils<SkPath> {
    static void Write(SkWriteBuffer& writer, const SkPath* path) {
        writer.writePath(*path);
    }
    static void Read(SkReadBuffer& reader, SkPath* path) {
        reader.readPath(path);
    }
};

template<> struct SerializationUtils<SkRegion> {
    static void Write(SkWriteBuffer& writer, const SkRegion* region) {
        writer.writeRegion(*region);
    }
    static void Read(SkReadBuffer& reader, SkRegion* region) {
        reader.readRegion(region);
    }
};

template<> struct SerializationUtils<SkString> {
    static void Write(SkWriteBuffer& writer, const SkString* string) {
        writer.writeString(string->c_str());
    }
    static void Read(SkReadBuffer& reader, SkString* string) {
        reader.readString(string);
    }
};

template<> struct SerializationUtils<unsigned char> {
    static void Write(SkWriteBuffer& writer, unsigned char* data, uint32_t arraySize) {
        writer.writeByteArray(data, arraySize);
    }
    static bool Read(SkReadBuffer& reader, unsigned char* data, uint32_t arraySize) {
        return reader.readByteArray(data, arraySize);
    }
};

template<> struct SerializationUtils<SkColor> {
    static void Write(SkWriteBuffer& writer, SkColor* data, uint32_t arraySize) {
        writer.writeColorArray(data, arraySize);
    }
    static bool Read(SkReadBuffer& reader, SkColor* data, uint32_t arraySize) {
        return reader.readColorArray(data, arraySize);
    }
};

template<> struct SerializationUtils<SkColor4f> {
    static void Write(SkWriteBuffer& writer, SkColor4f* data, uint32_t arraySize) {
        writer.writeColor4fArray(data, arraySize);
    }
    static bool Read(SkReadBuffer& reader, SkColor4f* data, uint32_t arraySize) {
        return reader.readColor4fArray(data, arraySize);
    }
};

template<> struct SerializationUtils<int32_t> {
    static void Write(SkWriteBuffer& writer, int32_t* data, uint32_t arraySize) {
        writer.writeIntArray(data, arraySize);
    }
    static bool Read(SkReadBuffer& reader, int32_t* data, uint32_t arraySize) {
        return reader.readIntArray(data, arraySize);
    }
};

template<> struct SerializationUtils<SkPoint> {
    static void Write(SkWriteBuffer& writer, SkPoint* data, uint32_t arraySize) {
        writer.writePointArray(data, arraySize);
    }
    static bool Read(SkReadBuffer& reader, SkPoint* data, uint32_t arraySize) {
        return reader.readPointArray(data, arraySize);
    }
};

template<> struct SerializationUtils<SkPoint3> {
    static void Write(SkWriteBuffer& writer, const SkPoint3* data) {
        writer.writePoint3(*data);
    }
    static void Read(SkReadBuffer& reader, SkPoint3* data) {
        reader.readPoint3(data);
    }
};

template<> struct SerializationUtils<SkScalar> {
    static void Write(SkWriteBuffer& writer, SkScalar* data, uint32_t arraySize) {
        writer.writeScalarArray(data, arraySize);
    }
    static bool Read(SkReadBuffer& reader, SkScalar* data, uint32_t arraySize) {
        return reader.readScalarArray(data, arraySize);
    }
};

template<typename T, bool testInvalid> struct SerializationTestUtils {
    static void InvalidateData(unsigned char* data) {}
};

template<> struct SerializationTestUtils<SkString, true> {
    static void InvalidateData(unsigned char* data) {
        data[3] |= 0x80; // Reverse sign of 1st integer
    }
};

template<typename T, bool testInvalid>
static void TestObjectSerializationNoAlign(T* testObj, skiatest::Reporter* reporter) {
    SkBinaryWriteBuffer writer({});
    SerializationUtils<T>::Write(writer, testObj);
    size_t bytesWritten = writer.bytesWritten();
    REPORTER_ASSERT(reporter, SkAlign4(bytesWritten) == bytesWritten);

    unsigned char dataWritten[1024];
    writer.writeToMemory(dataWritten);

    SerializationTestUtils<T, testInvalid>::InvalidateData(dataWritten);

    // Make sure this fails when it should (test with smaller size, but still multiple of 4)
    SkReadBuffer buffer(dataWritten, bytesWritten - 4);
    T obj;
    SerializationUtils<T>::Read(buffer, &obj);
    REPORTER_ASSERT(reporter, !buffer.isValid());

    // Make sure this succeeds when it should
    SkReadBuffer buffer2(dataWritten, bytesWritten);
    size_t offsetBefore = buffer2.offset();
    T obj2;
    SerializationUtils<T>::Read(buffer2, &obj2);
    size_t offsetAfter = buffer2.offset();
    // This should have succeeded, since there are enough bytes to read this
    REPORTER_ASSERT(reporter, buffer2.isValid() == !testInvalid);
    // Note: This following test should always succeed, regardless of whether the buffer is valid,
    // since if it is invalid, it will simply skip to the end, as if it had read the whole buffer.
    REPORTER_ASSERT(reporter, offsetAfter - offsetBefore == bytesWritten);
}

template<typename T>
static void TestObjectSerialization(T* testObj, skiatest::Reporter* reporter) {
    TestObjectSerializationNoAlign<T, false>(testObj, reporter);
    SerializationTest::TestAlignment(testObj, reporter);
}

template<typename T>
static T* TestFlattenableSerialization(T* testObj, bool shouldSucceed,
                                       skiatest::Reporter* reporter) {
    SkBinaryWriteBuffer writer({});
    SerializationUtils<T>::Write(writer, testObj);
    size_t bytesWritten = writer.bytesWritten();
    REPORTER_ASSERT(reporter, SkAlign4(bytesWritten) == bytesWritten);

    SkASSERT(bytesWritten <= 4096);
    unsigned char dataWritten[4096];
    writer.writeToMemory(dataWritten);

    // Make sure this fails when it should (test with smaller size, but still multiple of 4)
    SkReadBuffer buffer(dataWritten, bytesWritten - 4);
    T* obj = nullptr;
    SerializationUtils<T>::Read(buffer, &obj);
    REPORTER_ASSERT(reporter, !buffer.isValid());
    REPORTER_ASSERT(reporter, nullptr == obj);

    // Make sure this succeeds when it should
    SkReadBuffer buffer2(dataWritten, bytesWritten);
    const unsigned char* peekBefore = static_cast<const unsigned char*>(buffer2.skip(0));
    T* obj2 = nullptr;
    SerializationUtils<T>::Read(buffer2, &obj2);
    const unsigned char* peekAfter = static_cast<const unsigned char*>(buffer2.skip(0));
    if (shouldSucceed) {
        // This should have succeeded, since there are enough bytes to read this
        REPORTER_ASSERT(reporter, buffer2.isValid());
        REPORTER_ASSERT(reporter, static_cast<size_t>(peekAfter - peekBefore) == bytesWritten);
        REPORTER_ASSERT(reporter, obj2);
    } else {
        // If the deserialization was supposed to fail, make sure it did
        REPORTER_ASSERT(reporter, !buffer.isValid());
        REPORTER_ASSERT(reporter, nullptr == obj2);
    }

    return obj2; // Return object to perform further validity tests on it
}

template<typename T>
static void TestArraySerialization(T* data, skiatest::Reporter* reporter) {
    SkBinaryWriteBuffer writer({});
    SerializationUtils<T>::Write(writer, data, kArraySize);
    size_t bytesWritten = writer.bytesWritten();
    // This should write the length (in 4 bytes) and the array
    REPORTER_ASSERT(reporter, (4 + kArraySize * sizeof(T)) == bytesWritten);

    unsigned char dataWritten[2048];
    writer.writeToMemory(dataWritten);

    // Make sure this fails when it should
    SkReadBuffer buffer(dataWritten, bytesWritten);
    T dataRead[kArraySize];
    bool success = SerializationUtils<T>::Read(buffer, dataRead, kArraySize / 2);
    // This should have failed, since the provided size was too small
    REPORTER_ASSERT(reporter, !success);

    // Make sure this succeeds when it should
    SkReadBuffer buffer2(dataWritten, bytesWritten);
    success = SerializationUtils<T>::Read(buffer2, dataRead, kArraySize);
    // This should have succeeded, since there are enough bytes to read this
    REPORTER_ASSERT(reporter, success);
}

static void TestBitmapSerialization(const SkBitmap& validBitmap,
                                    const SkBitmap& invalidBitmap,
                                    bool shouldSucceed,
                                    skiatest::Reporter* reporter) {
    sk_sp<SkImage> validImage(validBitmap.asImage());
    sk_sp<SkImageFilter> validBitmapSource(SkImageFilters::Image(std::move(validImage),
                                                                 SkFilterMode::kNearest));
    sk_sp<SkImage> invalidImage(invalidBitmap.asImage());
    sk_sp<SkImageFilter> invalidBitmapSource(SkImageFilters::Image(std::move(invalidImage),
                                                                   SkFilterMode::kNearest));
    sk_sp<SkImageFilter> xfermodeImageFilter(
        SkImageFilters::Blend(SkBlendMode::kSrcOver,
                              std::move(invalidBitmapSource),
                              std::move(validBitmapSource), nullptr));

    sk_sp<SkImageFilter> deserializedFilter(
        TestFlattenableSerialization<SkImageFilter_Base>(
            (SkImageFilter_Base*)xfermodeImageFilter.get(), shouldSucceed, reporter));

    // Try to render a small bitmap using the invalid deserialized filter
    // to make sure we don't crash while trying to render it
    if (shouldSucceed) {
        SkBitmap bitmap;
        bitmap.allocN32Pixels(24, 24);
        SkCanvas canvas(bitmap);
        canvas.clear(0x00000000);
        SkPaint paint;
        paint.setImageFilter(deserializedFilter);
        canvas.clipRect(SkRect::MakeXYWH(0, 0, SkIntToScalar(24), SkIntToScalar(24)));
        canvas.drawImage(bitmap.asImage(), 0, 0, SkSamplingOptions(), &paint);
    }
}

static void TestColorFilterSerialization(skiatest::Reporter* reporter) {
    uint8_t table[256];
    for (int i = 0; i < 256; ++i) {
        table[i] = (i * 41) % 256;
    }
    auto filter = SkColorFilters::Table(table);
    sk_sp<SkColorFilter> copy(
        TestFlattenableSerialization(as_CFB(filter.get()), true, reporter));
}

static SkBitmap draw_picture(SkPicture& picture) {
     SkBitmap bitmap;
     bitmap.allocN32Pixels(SkScalarCeilToInt(picture.cullRect().width()),
                           SkScalarCeilToInt(picture.cullRect().height()));
     SkCanvas canvas(bitmap);
     picture.playback(&canvas);
     return bitmap;
}

static void compare_bitmaps(skiatest::Reporter* reporter,
                            const SkBitmap& b1, const SkBitmap& b2) {
    REPORTER_ASSERT(reporter, b1.width() == b2.width());
    REPORTER_ASSERT(reporter, b1.height() == b2.height());

    if ((b1.width() != b2.width()) ||
        (b1.height() != b2.height())) {
        return;
    }

    int pixelErrors = 0;
    for (int y = 0; y < b2.height(); ++y) {
        for (int x = 0; x < b2.width(); ++x) {
            if (b1.getColor(x, y) != b2.getColor(x, y))
                ++pixelErrors;
        }
    }
    REPORTER_ASSERT(reporter, 0 == pixelErrors);
}

static sk_sp<SkData> serialize_typeface_proc(SkTypeface* typeface, void* ctx) {
    // Write out typeface ID followed by entire typeface.
    SkDynamicMemoryWStream stream;
    sk_sp<SkData> data(typeface->serialize(SkTypeface::SerializeBehavior::kDoIncludeData));
    uint32_t typeface_id = typeface->uniqueID();
    stream.write(&typeface_id, sizeof(typeface_id));
    stream.write(data->data(), data->size());
    return stream.detachAsData();
}

static sk_sp<SkTypeface> deserialize_typeface_proc(const void* data, size_t length, void* ctx) {
    SkStream* stream;
    if (length < sizeof(stream)) {
        return nullptr;
    }
    memcpy(&stream, data, sizeof(stream));

    SkTypefaceID id;
    if (!stream->read(&id, sizeof(id))) {
        return nullptr;
    }

    sk_sp<SkTypeface> typeface = SkTypeface::MakeDeserialize(stream);
    return typeface;
}

static void serialize_and_compare_typeface(sk_sp<SkTypeface> typeface,
                                           const char* text,
                                           const SkSerialProcs* serial_procs,
                                           const SkDeserialProcs* deserial_procs,
                                           skiatest::Reporter* reporter) {
    // Create a font with the typeface.
    SkPaint paint;
    paint.setColor(SK_ColorGRAY);
    SkFont font(std::move(typeface), 30);

    // Paint some text.
    SkPictureRecorder recorder;
    SkIRect canvasRect = SkIRect::MakeWH(kBitmapSize, kBitmapSize);
    SkCanvas* canvas = recorder.beginRecording(SkIntToScalar(canvasRect.width()),
                                               SkIntToScalar(canvasRect.height()));
    canvas->drawColor(SK_ColorWHITE);
    canvas->drawString(text, 24, 32, font, paint);
    sk_sp<SkPicture> picture(recorder.finishRecordingAsPicture());

    // Serlialize picture and create its clone from stream.
    SkDynamicMemoryWStream stream;
    picture->serialize(&stream, serial_procs);
    std::unique_ptr<SkStream> inputStream(stream.detachAsStream());
    sk_sp<SkPicture> loadedPicture(SkPicture::MakeFromStream(inputStream.get(), deserial_procs));

    // Draw both original and clone picture and compare bitmaps -- they should be identical.
    SkBitmap origBitmap = draw_picture(*picture);
    SkBitmap destBitmap = draw_picture(*loadedPicture);
    compare_bitmaps(reporter, origBitmap, destBitmap);
}

static sk_sp<SkTypeface> makeDistortableWithNonDefaultAxes(skiatest::Reporter* reporter) {
    std::unique_ptr<SkStreamAsset> distortable(GetResourceAsStream("fonts/Distortable.ttf"));
    if (!distortable) {
        REPORT_FAILURE(reporter, "distortable", SkString());
        return nullptr;
    }

    const SkFontArguments::VariationPosition::Coordinate position[] = {
        { SkSetFourByteTag('w','g','h','t'), SK_ScalarSqrt2 },
    };
    SkFontArguments params;
    params.setVariationDesignPosition({position, std::size(position)});

    sk_sp<SkFontMgr> fm = SkFontMgr::RefDefault();

    sk_sp<SkTypeface> typeface = fm->makeFromStream(std::move(distortable), params);
    if (!typeface) {
        return nullptr;  // Not all SkFontMgr can makeFromStream().
    }

    int count = typeface->getVariationDesignPosition(nullptr, 0);
    if (count == -1) {
        return nullptr;  // The number of axes is unknown.
    }

    return typeface;
}

static void TestPictureTypefaceSerialization(const SkSerialProcs* serial_procs,
                                             const SkDeserialProcs* deserial_procs,
                                             skiatest::Reporter* reporter) {
    {
        // Load typeface from file to test CreateFromFile with index.
        auto typeface = MakeResourceAsTypeface("fonts/test.ttc", 1);
        if (!typeface) {
            INFOF(reporter, "Could not run fontstream test because test.ttc not found.");
        } else {
            serialize_and_compare_typeface(std::move(typeface), "A!", serial_procs, deserial_procs,
                                           reporter);
        }
    }

    {
        // Load typeface as stream to create with axis settings.
        auto typeface = makeDistortableWithNonDefaultAxes(reporter);
        if (!typeface) {
            INFOF(reporter, "Could not run fontstream test because Distortable.ttf not created.");
        } else {
            serialize_and_compare_typeface(std::move(typeface), "ab", serial_procs,
                                            deserial_procs, reporter);
        }
    }
}

SkString DumpTypeface(const SkTypeface& typeface) {
    int index;
    std::unique_ptr<SkStreamAsset> typefaceStream = typeface.openStream(&index);
    if (!typefaceStream) {
        return SkString("No Stream");
    }
    size_t length = typefaceStream->getLength();

    SkString s;
    s.appendf("Index: %d\n", index);
    s.appendf("Length: %zu\n", length);
    return s;
}
SkString DumpFontMetrics(const SkFontMetrics& metrics) {
    SkString m("Flags:\n");

    if (metrics.fFlags == 0) {
        m += "  No flags\n";
    } else {
        if (metrics.fFlags & SkFontMetrics::kUnderlineThicknessIsValid_Flag) {
            m += "  UnderlineThicknessIsValid\n";
        }
        if (metrics.fFlags & SkFontMetrics::kUnderlinePositionIsValid_Flag) {
            m += "  kUnderlinePositionIsValid\n";
        }
        if (metrics.fFlags & SkFontMetrics::kStrikeoutThicknessIsValid_Flag) {
            m += "  kStrikeoutThicknessIsValid\n";
        }
        if (metrics.fFlags & SkFontMetrics::kStrikeoutPositionIsValid_Flag) {
            m += "  kStrikeoutPositionIsValid\n";
        }
        if (metrics.fFlags & SkFontMetrics::kBoundsInvalid_Flag) {
            m += "  kBoundsInvalid\n";
        }
    }

    m.appendf("Top: %f\n", metrics.fTop);
    m.appendf("Ascent: %f\n", metrics.fAscent);
    m.appendf("Descent: %f\n", metrics.fDescent);
    m.appendf("Bottom: %f\n", metrics.fBottom);
    m.appendf("Leading: %f\n", metrics.fLeading);
    m.appendf("AvgCharWidth: %f\n", metrics.fAvgCharWidth);
    m.appendf("MaxCharWidth: %f\n", metrics.fMaxCharWidth);
    m.appendf("XMin: %f\n", metrics.fXMin);
    m.appendf("XMax: %f\n", metrics.fXMax);
    m.appendf("XHeight: %f\n", metrics.fXHeight);
    m.appendf("CapHeight: %f\n", metrics.fCapHeight);
    m.appendf("UnderlineThickness: %f\n", metrics.fUnderlineThickness);
    m.appendf("UnderlinePosition: %f\n", metrics.fUnderlinePosition);
    m.appendf("StrikeoutThickness: %f\n", metrics.fStrikeoutThickness);
    m.appendf("StrikeoutPosition: %f\n", metrics.fStrikeoutPosition);
    return m;
}
static void TestTypefaceSerialization(skiatest::Reporter* reporter, sk_sp<SkTypeface> typeface) {
    SkDynamicMemoryWStream typefaceWStream;
    typeface->serialize(&typefaceWStream);

    std::unique_ptr<SkStream> typefaceStream = typefaceWStream.detachAsStream();
    sk_sp<SkTypeface> cloneTypeface = SkTypeface::MakeDeserialize(typefaceStream.get());
    SkASSERT(cloneTypeface);

    SkString name, cloneName;
    typeface->getFamilyName(&name);
    cloneTypeface->getFamilyName(&cloneName);

    REPORTER_ASSERT(reporter, typeface->countGlyphs() == cloneTypeface->countGlyphs(),
        "Typeface: \"%s\" CloneTypeface: \"%s\"", name.c_str(), cloneName.c_str());
    REPORTER_ASSERT(reporter, typeface->fontStyle() == cloneTypeface->fontStyle(),
        "Typeface: \"%s\" CloneTypeface: \"%s\"", name.c_str(), cloneName.c_str());

    SkFont font(typeface, 12);
    SkFont clone(cloneTypeface, 12);
    SkFontMetrics fontMetrics, cloneMetrics;
    font.getMetrics(&fontMetrics);
    clone.getMetrics(&cloneMetrics);
    REPORTER_ASSERT(reporter, fontMetrics == cloneMetrics,
        "Typeface: \"%s\"\n-Metrics---\n%s-Data---\n%s\n\n"
        "CloneTypeface: \"%s\"\n-Metrics---\n%s-Data---\n%s",
        name.c_str(),
        DumpFontMetrics(fontMetrics).c_str(),
        DumpTypeface(*typeface).c_str(),
        cloneName.c_str(),
        DumpFontMetrics(cloneMetrics).c_str(),
        DumpTypeface(*cloneTypeface).c_str());
}
DEF_TEST(Serialization_Typeface, reporter) {
    SkFont font;
    TestTypefaceSerialization(reporter, font.refTypefaceOrDefault());
    TestTypefaceSerialization(reporter, ToolUtils::sample_user_typeface());
}

static void setup_bitmap_for_canvas(SkBitmap* bitmap) {
    bitmap->allocN32Pixels(kBitmapSize, kBitmapSize);
}

static sk_sp<SkImage> make_checkerboard_image() {
    SkBitmap bitmap;
    setup_bitmap_for_canvas(&bitmap);

    SkCanvas canvas(bitmap);
    canvas.clear(0x00000000);
    SkPaint darkPaint;
    darkPaint.setColor(0xFF804020);
    SkPaint lightPaint;
    lightPaint.setColor(0xFF244484);
    const int i = kBitmapSize / 8;
    const SkScalar f = SkIntToScalar(i);
    for (int y = 0; y < kBitmapSize; y += i) {
        for (int x = 0; x < kBitmapSize; x += i) {
            canvas.save();
            canvas.translate(SkIntToScalar(x), SkIntToScalar(y));
            canvas.drawRect(SkRect::MakeXYWH(0, 0, f, f), darkPaint);
            canvas.drawRect(SkRect::MakeXYWH(f, 0, f, f), lightPaint);
            canvas.drawRect(SkRect::MakeXYWH(0, f, f, f), lightPaint);
            canvas.drawRect(SkRect::MakeXYWH(f, f, f, f), darkPaint);
            canvas.restore();
        }
    }
    return bitmap.asImage();
}

static void draw_something(SkCanvas* canvas) {
    canvas->save();
    canvas->scale(0.5f, 0.5f);
    canvas->drawImage(make_checkerboard_image(), 0, 0);
    canvas->restore();

    SkPaint paint;
    paint.setAntiAlias(true);
    paint.setColor(SK_ColorRED);
    canvas->drawCircle(SkIntToScalar(kBitmapSize/2), SkIntToScalar(kBitmapSize/2), SkIntToScalar(kBitmapSize/3), paint);
    paint.setColor(SK_ColorBLACK);

    SkFont font;
    font.setSize(kBitmapSize/3);
    canvas->drawString("Picture", SkIntToScalar(kBitmapSize/2), SkIntToScalar(kBitmapSize/4), font, paint);
}

static sk_sp<SkImage> render(const SkPicture& p) {
    auto surf = SkSurfaces::Raster(SkImageInfo::MakeN32Premul(
            SkScalarRoundToInt(p.cullRect().width()), SkScalarRoundToInt(p.cullRect().height())));
    if (!surf) {
        return nullptr; // bounds are empty?
    }
    surf->getCanvas()->clear(SK_ColorWHITE);
    p.playback(surf->getCanvas());
    return surf->makeImageSnapshot();
}

DEF_TEST(Serialization, reporter) {
    // Test matrix serialization
    {
        SkMatrix matrix = SkMatrix::I();
        TestObjectSerialization(&matrix, reporter);
    }

    // Test point3 serialization
    {
        SkPoint3 point;
        TestObjectSerializationNoAlign<SkPoint3, false>(&point, reporter);
    }

    // Test path serialization
    {
        SkPath path;
        TestObjectSerialization(&path, reporter);
    }

    // Test region serialization
    {
        SkRegion region;
        TestObjectSerialization(&region, reporter);
    }

    // Test color filter serialization
    {
        TestColorFilterSerialization(reporter);
    }

    // Test string serialization
    {
        SkString string("string");
        TestObjectSerializationNoAlign<SkString, false>(&string, reporter);
        TestObjectSerializationNoAlign<SkString, true>(&string, reporter);
    }

    // Test rrect serialization
    {
        // SkRRect does not initialize anything.
        // An uninitialized SkRRect can be serialized,
        // but will branch on uninitialized data when deserialized.
        SkRRect rrect;
        SkRect rect = SkRect::MakeXYWH(1, 2, 20, 30);
        SkVector corners[4] = { {1, 2}, {2, 3}, {3,4}, {4,5} };
        rrect.setRectRadii(rect, corners);
        SerializationTest::TestAlignment(&rrect, reporter);
    }

    // Test readByteArray
    {
        unsigned char data[kArraySize] = { 1, 2, 3 };
        TestArraySerialization(data, reporter);
    }

    // Test readColorArray
    {
        SkColor data[kArraySize] = { SK_ColorBLACK, SK_ColorWHITE, SK_ColorRED };
        TestArraySerialization(data, reporter);
    }

    // Test readColor4fArray
    {
        SkColor4f data[kArraySize] = {
            SkColor4f::FromColor(SK_ColorBLACK),
            SkColor4f::FromColor(SK_ColorWHITE),
            SkColor4f::FromColor(SK_ColorRED),
            { 1.f, 2.f, 4.f, 8.f }
        };
        TestArraySerialization(data, reporter);
    }

    // Test readIntArray
    {
        int32_t data[kArraySize] = { 1, 2, 4, 8 };
        TestArraySerialization(data, reporter);
    }

    // Test readPointArray
    {
        SkPoint data[kArraySize] = { {6, 7}, {42, 128} };
        TestArraySerialization(data, reporter);
    }

    // Test readScalarArray
    {
        SkScalar data[kArraySize] = { SK_Scalar1, SK_ScalarHalf, SK_ScalarMax };
        TestArraySerialization(data, reporter);
    }

    // Test skipByteArray
    {
        // Valid case with non-empty array:
        {
            unsigned char data[kArraySize] = { 1, 2, 3 };
	    SkBinaryWriteBuffer writer({});
	    writer.writeByteArray(data, kArraySize);
	    SkAutoMalloc buf(writer.bytesWritten());
	    writer.writeToMemory(buf.get());

	    SkReadBuffer reader(buf.get(), writer.bytesWritten());
	    size_t len = ~0;
	    const void* arr = reader.skipByteArray(&len);
	    REPORTER_ASSERT(reporter, arr);
	    REPORTER_ASSERT(reporter, len == kArraySize);
	    REPORTER_ASSERT(reporter, memcmp(arr, data, len) == 0);
        }

        // Writing a zero length array (can be detected as valid by non-nullptr return):
        {
            SkBinaryWriteBuffer writer({});
            writer.writeByteArray(nullptr, 0);
            SkAutoMalloc buf(writer.bytesWritten());
            writer.writeToMemory(buf.get());

            SkReadBuffer reader(buf.get(), writer.bytesWritten());
            size_t len = ~0;
            const void* arr = reader.skipByteArray(&len);
            REPORTER_ASSERT(reporter, arr);
            REPORTER_ASSERT(reporter, len == 0);
        }

        // If the array can't be safely read, should return nullptr:
        {
            SkBinaryWriteBuffer writer({});
            writer.writeUInt(kArraySize);
            SkAutoMalloc buf(writer.bytesWritten());
            writer.writeToMemory(buf.get());

            SkReadBuffer reader(buf.get(), writer.bytesWritten());
            size_t len = ~0;
            const void* arr = reader.skipByteArray(&len);
            REPORTER_ASSERT(reporter, !arr);
            REPORTER_ASSERT(reporter, len == 0);
        }
    }

    // Test invalid deserializations
    {
        SkImageInfo info = SkImageInfo::MakeN32Premul(kBitmapSize, kBitmapSize);

        SkBitmap validBitmap;
        validBitmap.setInfo(info);

        // Create a bitmap with a really large height
        SkBitmap invalidBitmap;
        invalidBitmap.setInfo(info.makeWH(info.width(), 1000000000));

        // The deserialization should succeed, and the rendering shouldn't crash,
        // even when the device fails to initialize, due to its size
        TestBitmapSerialization(validBitmap, invalidBitmap, true, reporter);
    }

    // Test simple SkPicture serialization
    {
        SkPictureRecorder recorder;
        draw_something(recorder.beginRecording(SkIntToScalar(kBitmapSize),
                                               SkIntToScalar(kBitmapSize)));
        sk_sp<SkPicture> pict(recorder.finishRecordingAsPicture());

        // Serialize picture
        SkSerialProcs sProcs;
        sProcs.fImageProc = [](SkImage* img, void*) -> sk_sp<SkData> {
            return SkPngEncoder::Encode(nullptr, img, SkPngEncoder::Options{});
        };
        SkBinaryWriteBuffer writer(sProcs);

        SkPicturePriv::Flatten(pict, writer);
        size_t size = writer.bytesWritten();
        AutoTMalloc<unsigned char> data(size);
        writer.writeToMemory(static_cast<void*>(data.get()));

        // Deserialize picture
        SkReadBuffer reader(static_cast<void*>(data.get()), size);
        sk_sp<SkPicture> readPict(SkPicturePriv::MakeFromBuffer(reader));
        REPORTER_ASSERT(reporter, reader.isValid());
        REPORTER_ASSERT(reporter, readPict.get());
        sk_sp<SkImage> img0 = render(*pict);
        sk_sp<SkImage> img1 = render(*readPict);
        if (img0 && img1) {
            REPORTER_ASSERT(reporter, ToolUtils::equal_pixels(img0.get(), img1.get()));
        }
    }

    TestPictureTypefaceSerialization(nullptr, nullptr, reporter);

    SkSerialProcs serial_procs;
    serial_procs.fTypefaceProc = serialize_typeface_proc;
    SkDeserialProcs deserial_procs;
    deserial_procs.fTypefaceProc = deserialize_typeface_proc;
    TestPictureTypefaceSerialization(&serial_procs, &deserial_procs, reporter);
}

///////////////////////////////////////////////////////////////////////////////////////////////////

static sk_sp<SkPicture> copy_picture_via_serialization(SkPicture* src) {
    SkDynamicMemoryWStream wstream;
    src->serialize(&wstream, nullptr);  // default is fine, no SkImages to encode
    std::unique_ptr<SkStreamAsset> rstream(wstream.detachAsStream());
    return SkPicture::MakeFromStream(rstream.get());
}

struct AnnotationRec {
    const SkRect    fRect;
    const char*     fKey;
    sk_sp<SkData>   fValue;
};

class TestAnnotationCanvas : public SkCanvas {
    skiatest::Reporter*     fReporter;
    const AnnotationRec*    fRec;
    int                     fCount;
    int                     fCurrIndex;

public:
    TestAnnotationCanvas(skiatest::Reporter* reporter, const AnnotationRec rec[], int count)
        : SkCanvas(100, 100)
        , fReporter(reporter)
        , fRec(rec)
        , fCount(count)
        , fCurrIndex(0)
    {}

    ~TestAnnotationCanvas() override {
        REPORTER_ASSERT(fReporter, fCount == fCurrIndex);
    }

protected:
    void onDrawAnnotation(const SkRect& rect, const char key[], SkData* value) override {
        REPORTER_ASSERT(fReporter, fCurrIndex < fCount);
        REPORTER_ASSERT(fReporter, rect == fRec[fCurrIndex].fRect);
        REPORTER_ASSERT(fReporter, !strcmp(key, fRec[fCurrIndex].fKey));
        REPORTER_ASSERT(fReporter, value->equals(fRec[fCurrIndex].fValue.get()));
        fCurrIndex += 1;
    }
};

/*
 *  Test the 3 annotation types by recording them into a picture, serializing, and then playing
 *  them back into another canvas.
 */
DEF_TEST(Annotations, reporter) {
    SkPictureRecorder recorder;
    SkCanvas* recordingCanvas = recorder.beginRecording(SkRect::MakeWH(100, 100));

    const char* str0 = "rect-with-url";
    const SkRect r0 = SkRect::MakeWH(10, 10);
    sk_sp<SkData> d0(SkData::MakeWithCString(str0));
    SkAnnotateRectWithURL(recordingCanvas, r0, d0.get());

    const char* str1 = "named-destination";
    const SkRect r1 = SkRect::MakeXYWH(5, 5, 0, 0); // collapsed to a point
    sk_sp<SkData> d1(SkData::MakeWithCString(str1));
    SkAnnotateNamedDestination(recordingCanvas, {r1.x(), r1.y()}, d1.get());

    const char* str2 = "link-to-destination";
    const SkRect r2 = SkRect::MakeXYWH(20, 20, 5, 6);
    sk_sp<SkData> d2(SkData::MakeWithCString(str2));
    SkAnnotateLinkToDestination(recordingCanvas, r2, d2.get());

    const AnnotationRec recs[] = {
        { r0, SkAnnotationKeys::URL_Key(),                  std::move(d0) },
        { r1, SkAnnotationKeys::Define_Named_Dest_Key(),    std::move(d1) },
        { r2, SkAnnotationKeys::Link_Named_Dest_Key(),      std::move(d2) },
    };

    sk_sp<SkPicture> pict0(recorder.finishRecordingAsPicture());
    sk_sp<SkPicture> pict1(copy_picture_via_serialization(pict0.get()));

    TestAnnotationCanvas canvas(reporter, recs, std::size(recs));
    canvas.drawPicture(pict1);
}

DEF_TEST(WriteBuffer_storage, reporter) {
    enum {
        kSize = 32
    };
    int32_t storage[kSize/4];
    char src[kSize];
    sk_bzero(src, kSize);

    SkBinaryWriteBuffer writer(storage, kSize, {});
    REPORTER_ASSERT(reporter, writer.usingInitialStorage());
    REPORTER_ASSERT(reporter, writer.bytesWritten() == 0);
    writer.write(src, kSize - 4);
    REPORTER_ASSERT(reporter, writer.usingInitialStorage());
    REPORTER_ASSERT(reporter, writer.bytesWritten() == kSize - 4);
    writer.writeInt(0);
    REPORTER_ASSERT(reporter, writer.usingInitialStorage());
    REPORTER_ASSERT(reporter, writer.bytesWritten() == kSize);

    writer.reset(storage, kSize-4);
    REPORTER_ASSERT(reporter, writer.usingInitialStorage());
    REPORTER_ASSERT(reporter, writer.bytesWritten() == 0);
    writer.write(src, kSize - 4);
    REPORTER_ASSERT(reporter, writer.usingInitialStorage());
    REPORTER_ASSERT(reporter, writer.bytesWritten() == kSize - 4);
    writer.writeInt(0);
    REPORTER_ASSERT(reporter, !writer.usingInitialStorage());   // this is the change
    REPORTER_ASSERT(reporter, writer.bytesWritten() == kSize);
}

DEF_TEST(WriteBuffer_external_memory_textblob, reporter) {
    SkFont font;
    font.setTypeface(SkTypeface::MakeDefault());

    SkTextBlobBuilder builder;
    int glyph_count = 5;
    const auto& run = builder.allocRun(font, glyph_count, 1.2f, 2.3f);
    // allocRun() allocates only the glyph buffer.
    std::fill(run.glyphs, run.glyphs + glyph_count, 0);
    auto blob = builder.make();
    SkSerialProcs procs;
    AutoTMalloc<uint8_t> storage;
    size_t blob_size = 0u;
    size_t storage_size = 0u;

    blob_size = SkAlign4(blob->serialize(procs)->size());
    REPORTER_ASSERT(reporter, blob_size > 4u);
    storage_size = blob_size - 4;
    storage.realloc(storage_size);
    REPORTER_ASSERT(reporter, blob->serialize(procs, storage.get(), storage_size) == 0u);
    storage_size = blob_size;
    storage.realloc(storage_size);
    REPORTER_ASSERT(reporter, blob->serialize(procs, storage.get(), storage_size) != 0u);
}

DEF_TEST(WriteBuffer_external_memory_flattenable, reporter) {
    SkScalar intervals[] = {1.f, 1.f};
    auto path_effect = SkDashPathEffect::Make(intervals, 2, 0);
    size_t path_size = SkAlign4(path_effect->serialize()->size());
    REPORTER_ASSERT(reporter, path_size > 4u);
    AutoTMalloc<uint8_t> storage;

    size_t storage_size = path_size - 4;
    storage.realloc(storage_size);
    REPORTER_ASSERT(reporter, path_effect->serialize(storage.get(), storage_size) == 0u);

    storage_size = path_size;
    storage.realloc(storage_size);
    REPORTER_ASSERT(reporter, path_effect->serialize(storage.get(), storage_size) != 0u);
}

DEF_TEST(ReadBuffer_empty, reporter) {
    SkBinaryWriteBuffer writer({});
    writer.writeInt(123);
    writer.writeDataAsByteArray(SkData::MakeEmpty().get());
    writer.writeInt(321);

    size_t size = writer.bytesWritten();
    SkAutoMalloc storage(size);
    writer.writeToMemory(storage.get());

    SkReadBuffer reader(storage.get(), size);
    REPORTER_ASSERT(reporter, reader.readInt() == 123);
    auto data = reader.readByteArrayAsData();
    REPORTER_ASSERT(reporter, data->size() == 0);
    REPORTER_ASSERT(reporter, reader.readInt() == 321);
}