/*
 * Copyright 2017 Google Inc.
 *
 * Use of this source code is governed by a BSD-style license that can be
 * found in the LICENSE file.
 */

#include "gm/gm.h"
#include "include/codec/SkCodec.h"
#include "include/core/SkBitmap.h"
#include "include/core/SkCanvas.h"
#include "include/core/SkColor.h"
#include "include/core/SkColorSpace.h"
#include "include/core/SkData.h"
#include "include/core/SkImage.h"
#include "include/core/SkImageInfo.h"
#include "include/core/SkRefCnt.h"
#include "include/core/SkSize.h"
#include "include/core/SkString.h"
#include "include/gpu/GrDirectContext.h"
#include "src/core/SkImagePriv.h"
#include "tools/Resources.h"

#include <initializer_list>
#include <memory>

sk_sp<SkImage> make_raster_image(const char* path) {
    sk_sp<SkData> resourceData = GetResourceAsData(path);
    std::unique_ptr<SkCodec> codec = SkCodec::MakeFromData(resourceData);

    SkBitmap bitmap;
    bitmap.allocPixels(codec->getInfo());

    codec->getPixels(codec->getInfo(), bitmap.getPixels(), bitmap.rowBytes());
    return SkImage::MakeFromBitmap(bitmap);
}

sk_sp<SkImage> make_color_space(
        sk_sp<SkImage> orig, sk_sp<SkColorSpace> colorSpace, GrDirectContext* direct) {
    sk_sp<SkImage> xform = orig->makeColorSpace(colorSpace, direct);

    // Assign an sRGB color space on the xformed image, so we can see the effects of the xform
    // when we draw.
    sk_sp<SkColorSpace> srgb = SkColorSpace::MakeSRGB();
    if (colorSpace->gammaIsLinear()) {
        srgb = SkColorSpace::MakeSRGBLinear();
    }
    return xform->reinterpretColorSpace(std::move(srgb));
}

DEF_SIMPLE_GM_CAN_FAIL(makecolorspace, canvas, errorMsg, 128 * 3, 128 * 4) {
    sk_sp<SkColorSpace> wideGamut = SkColorSpace::MakeRGB(SkNamedTransferFn::kSRGB,
                                                          SkNamedGamut::kAdobeRGB);
    sk_sp<SkColorSpace> wideGamutLinear = wideGamut->makeLinearGamma();

    // Lazy images
    sk_sp<SkImage> opaqueImage = GetResourceAsImage("images/mandrill_128.png");
    sk_sp<SkImage> premulImage = GetResourceAsImage("images/color_wheel.png");
    if (!opaqueImage || !premulImage) {
        *errorMsg = "Failed to load images. Did you forget to set the resourcePath?";
        return skiagm::DrawResult::kFail;
    }
    auto direct = GrAsDirectContext(canvas->recordingContext());
    canvas->drawImage(opaqueImage, 0.0f, 0.0f);
    canvas->drawImage(make_color_space(opaqueImage, wideGamut, direct), 128.0f, 0.0f);
    canvas->drawImage(make_color_space(opaqueImage, wideGamutLinear, direct), 256.0f, 0.0f);
    canvas->drawImage(premulImage, 0.0f, 128.0f);
    canvas->drawImage(make_color_space(premulImage, wideGamut, direct), 128.0f, 128.0f);
    canvas->drawImage(make_color_space(premulImage, wideGamutLinear, direct), 256.0f, 128.0f);
    canvas->translate(0.0f, 256.0f);

    // Raster images
    opaqueImage = make_raster_image("images/mandrill_128.png");
    premulImage = make_raster_image("images/color_wheel.png");
    canvas->drawImage(opaqueImage, 0.0f, 0.0f);
    canvas->drawImage(make_color_space(opaqueImage, wideGamut, direct), 128.0f, 0.0f);
    canvas->drawImage(make_color_space(opaqueImage, wideGamutLinear, direct), 256.0f, 0.0f);
    canvas->drawImage(premulImage, 0.0f, 128.0f);
    canvas->drawImage(make_color_space(premulImage, wideGamut, direct), 128.0f, 128.0f);
    canvas->drawImage(make_color_space(premulImage, wideGamutLinear, direct), 256.0f, 128.0f);
    return skiagm::DrawResult::kOk;
}

DEF_SIMPLE_GM_BG(makecolortypeandspace, canvas, 128 * 3, 128 * 4, SK_ColorWHITE) {
    sk_sp<SkImage> images[] = {
        GetResourceAsImage("images/mandrill_128.png"),
        GetResourceAsImage("images/color_wheel.png"),
    };
    auto rec2020 = SkColorSpace::MakeRGB(SkNamedTransferFn::kSRGB, SkNamedGamut::kRec2020);

    // Use the lazy images on the first iteration, and concrete (raster/GPU) images on the second
    auto direct = GrAsDirectContext(canvas->recordingContext());
    for (bool lazy : {true, false}) {
        for (int j = 0; j < 2; ++j) {
            const SkImage* image = images[j].get();
            if (!image) {
                // Can happen on bots that abandon the GPU context
                continue;
            }

            // Unmodified
            canvas->drawImage(image, 0, 0);

            // Change the color type/space of the image in a couple ways. In both cases, codec
            // may fail, because we refude to decode transparent sources to opaque color types.
            // Guard against that, to avoid cascading failures in DDL.

            // 565 in a wide color space (should be visibly quantized). Fails with the color_wheel,
            // because of the codec issues mentioned above.
            auto image565 = image->makeColorTypeAndColorSpace(kRGB_565_SkColorType,
                                                              rec2020, direct);
            if (!lazy || image565->makeRasterImage()) {
                canvas->drawImage(image565, 128, 0);
            }

            // Grayscale in the original color space. This fails in even more cases, due to the
            // above opaque issue, and because Ganesh doesn't support drawing to gray, at all.
            auto imageGray = image->makeColorTypeAndColorSpace(kGray_8_SkColorType,
                                                               image->refColorSpace(),
                                                               direct);
            if (!lazy || imageGray->makeRasterImage()) {
                canvas->drawImage(imageGray, 256, 0);
            }

            images[j] = direct ? image->makeTextureImage(direct) : image->makeRasterImage();

            canvas->translate(0, 128);
        }
    }
}

DEF_SIMPLE_GM_CAN_FAIL(reinterpretcolorspace, canvas, errorMsg, 128 * 3, 128 * 3) {
    // We draw a 3x3 grid. The three rows are lazy (encoded), raster, and GPU (or another copy of
    // raster so all configs look similar). In each row, we draw three variants:
    // - The original image (should look normal).
    // - The image, reinterpreted as being in the color-spin space. The pixel data isn't changed,
    //   so in untagged configs, this looks like the first column. In tagged configs, this has the
    //   the effect of rotating the colors (RGB -> GBR).
    // - The image converted to the color-spin space, then reinterpreted as being sRGB. In all
    //   configs, this appears to be spun backwards (RGB -> BRG), and tests the composition of
    //   these two APIs.

    // In all cases, every column should be identical. In tagged configs, the 'R' in the columns
    // should be Red, Green, Blue.

    sk_sp<SkColorSpace> srgb = SkColorSpace::MakeSRGB();
    sk_sp<SkColorSpace> spin = srgb->makeColorSpin();
    sk_sp<SkImage> image = GetResourceAsImage("images/color_wheel.png");
    if (!image) {
        *errorMsg = "Failed to load image. Did you forget to set the resourcePath?";
        return skiagm::DrawResult::kFail;
    }

    // Lazy images
    canvas->drawImage(image, 0.0f, 0.0f);
    canvas->drawImage(image->reinterpretColorSpace(spin), 128.0f, 0.0f);
    canvas->drawImage(image->makeColorSpace(spin, nullptr)->reinterpretColorSpace(srgb),
                      256.0f, 0.0f);

    canvas->translate(0.0f, 128.0f);

    // Raster images
    image = image->makeRasterImage();
    canvas->drawImage(image, 0.0f, 0.0f);
    canvas->drawImage(image->reinterpretColorSpace(spin), 128.0f, 0.0f);
    canvas->drawImage(image->makeColorSpace(spin, nullptr)->reinterpretColorSpace(srgb),
                      256.0f, 0.0f);

    canvas->translate(0.0f, 128.0f);

    // GPU images
    auto direct = GrAsDirectContext(canvas->recordingContext());
    if (auto gpuImage = image->makeTextureImage(direct)) {
        image = gpuImage;
    }

    canvas->drawImage(image, 0.0f, 0.0f);
    canvas->drawImage(image->reinterpretColorSpace(spin), 128.0f, 0.0f);
    canvas->drawImage(image->makeColorSpace(spin, direct)->reinterpretColorSpace(srgb),
                      256.0f, 0.0f);

    return skiagm::DrawResult::kOk;
}