/*
 * Copyright 2021 The Android Open Source Project
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

#undef LOG_TAG
#define LOG_TAG "Planner"
// #define LOG_NDEBUG 0
#define ATRACE_TAG ATRACE_TAG_GRAPHICS

#include <android-base/properties.h>
#include <android-base/stringprintf.h>
#include <compositionengine/impl/OutputCompositionState.h>
#include <compositionengine/impl/planner/CachedSet.h>
#include <math/HashCombine.h>
#include <renderengine/DisplaySettings.h>
#include <renderengine/RenderEngine.h>
#include <ui/DebugUtils.h>
#include <ui/HdrRenderTypeUtils.h>
#include <utils/Trace.h>

namespace android::compositionengine::impl::planner {

const bool CachedSet::sDebugHighlighLayers =
        base::GetBoolProperty(std::string("debug.sf.layer_caching_highlight"), false);

std::string durationString(std::chrono::milliseconds duration) {
    using namespace std::chrono_literals;

    std::string result;

    if (duration >= 1h) {
        const auto hours = std::chrono::duration_cast<std::chrono::hours>(duration);
        base::StringAppendF(&result, "%d hr ", static_cast<int>(hours.count()));
        duration -= hours;
    }
    if (duration >= 1min) {
        const auto minutes = std::chrono::duration_cast<std::chrono::minutes>(duration);
        base::StringAppendF(&result, "%d min ", static_cast<int>(minutes.count()));
        duration -= minutes;
    }
    base::StringAppendF(&result, "%.3f sec ", duration.count() / 1000.0f);

    return result;
}

CachedSet::Layer::Layer(const LayerState* state, std::chrono::steady_clock::time_point lastUpdate)
      : mState(state), mHash(state->getHash()), mLastUpdate(lastUpdate) {}

CachedSet::CachedSet(const LayerState* layer, std::chrono::steady_clock::time_point lastUpdate)
      : mFingerprint(layer->getHash()), mLastUpdate(lastUpdate) {
    addLayer(layer, lastUpdate);
}

CachedSet::CachedSet(Layer layer)
      : mFingerprint(layer.getHash()),
        mLastUpdate(layer.getLastUpdate()),
        mBounds(layer.getDisplayFrame()),
        mVisibleRegion(layer.getVisibleRegion()) {
    mLayers.emplace_back(std::move(layer));
}

void CachedSet::addLayer(const LayerState* layer,
                         std::chrono::steady_clock::time_point lastUpdate) {
    mLayers.emplace_back(layer, lastUpdate);

    Region boundingRegion;
    boundingRegion.orSelf(mBounds);
    boundingRegion.orSelf(layer->getDisplayFrame());
    mBounds = boundingRegion.getBounds();
    mVisibleRegion.orSelf(layer->getVisibleRegion());
}

NonBufferHash CachedSet::getNonBufferHash() const {
    if (mLayers.size() == 1) {
        return mFingerprint;
    }

    // TODO(b/182614524): We sometimes match this with LayerState hashes. Determine if that is
    // necessary (and therefore we need to match implementations).
    size_t hash = 0;
    android::hashCombineSingle(hash, mBounds);
    android::hashCombineSingle(hash, mOutputDataspace);
    android::hashCombineSingle(hash, mOrientation);
    return hash;
}

size_t CachedSet::getComponentDisplayCost() const {
    size_t displayCost = 0;

    for (const Layer& layer : mLayers) {
        displayCost += static_cast<size_t>(layer.getDisplayFrame().width() *
                                           layer.getDisplayFrame().height());
    }

    return displayCost;
}

size_t CachedSet::getCreationCost() const {
    if (mLayers.size() == 1) {
        return 0;
    }

    // Reads
    size_t creationCost = getComponentDisplayCost();

    // Write - assumes that the output buffer only gets written once per pixel
    creationCost += static_cast<size_t>(mBounds.width() * mBounds.height());

    return creationCost;
}

size_t CachedSet::getDisplayCost() const {
    return static_cast<size_t>(mBounds.width() * mBounds.height());
}

bool CachedSet::hasBufferUpdate() const {
    for (const Layer& layer : mLayers) {
        if (layer.getFramesSinceBufferUpdate() == 0) {
            return true;
        }
    }
    return false;
}

bool CachedSet::hasReadyBuffer() const {
    return mTexture && mDrawFence->getStatus() == Fence::Status::Signaled;
}

std::vector<CachedSet> CachedSet::decompose() const {
    std::vector<CachedSet> layers;

    std::transform(mLayers.begin(), mLayers.end(), std::back_inserter(layers),
                   [](Layer layer) { return CachedSet(std::move(layer)); });

    return layers;
}

void CachedSet::updateAge(std::chrono::steady_clock::time_point now) {
    LOG_ALWAYS_FATAL_IF(mLayers.size() > 1, "[%s] This should only be called on single-layer sets",
                        __func__);

    if (mLayers[0].getFramesSinceBufferUpdate() == 0) {
        mLastUpdate = now;
        mAge = 0;
    }
}

void CachedSet::render(renderengine::RenderEngine& renderEngine, TexturePool& texturePool,
                       const OutputCompositionState& outputState,
                       bool deviceHandlesColorTransform) {
    ATRACE_CALL();
    if (outputState.powerCallback) {
        outputState.powerCallback->notifyCpuLoadUp();
    }
    const Rect& viewport = outputState.layerStackSpace.getContent();
    const ui::Dataspace& outputDataspace = outputState.dataspace;
    const ui::Transform::RotationFlags orientation =
            ui::Transform::toRotationFlags(outputState.framebufferSpace.getOrientation());

    renderengine::DisplaySettings displaySettings{
            .physicalDisplay = outputState.framebufferSpace.getContent(),
            .clip = viewport,
            .outputDataspace = outputDataspace,
            .colorTransform = outputState.colorTransformMatrix,
            .deviceHandlesColorTransform = deviceHandlesColorTransform,
            .orientation = orientation,
            .targetLuminanceNits = outputState.displayBrightnessNits,
    };

    LayerFE::ClientCompositionTargetSettings
            targetSettings{.clip = Region(viewport),
                           .needsFiltering = false,
                           .isSecure = outputState.isSecure,
                           .isProtected = false,
                           .viewport = viewport,
                           .dataspace = outputDataspace,
                           .realContentIsVisible = true,
                           .clearContent = false,
                           .blurSetting =
                                   LayerFE::ClientCompositionTargetSettings::BlurSetting::Enabled,
                           .whitePointNits = outputState.displayBrightnessNits,
                           .treat170mAsSrgb = outputState.treat170mAsSrgb};

    std::vector<renderengine::LayerSettings> layerSettings;
    renderengine::LayerSettings highlight;
    for (const auto& layer : mLayers) {
        if (auto clientCompositionSettings =
                    layer.getState()->getOutputLayer()->getLayerFE().prepareClientComposition(
                            targetSettings)) {
            layerSettings.push_back(std::move(*clientCompositionSettings));
        }
    }

    renderengine::LayerSettings blurLayerSettings;
    if (mBlurLayer) {
        auto blurSettings = targetSettings;
        blurSettings.blurSetting =
                LayerFE::ClientCompositionTargetSettings::BlurSetting::BackgroundBlurOnly;

        auto blurLayerSettings =
                mBlurLayer->getOutputLayer()->getLayerFE().prepareClientComposition(blurSettings);
        // This mimics Layer::prepareClearClientComposition
        blurLayerSettings->skipContentDraw = true;
        blurLayerSettings->name = std::string("blur layer");
        // Clear out the shadow settings
        blurLayerSettings->shadow = {};
        layerSettings.push_back(std::move(*blurLayerSettings));
    }

    if (mHolePunchLayer) {
        auto& layerFE = mHolePunchLayer->getOutputLayer()->getLayerFE();

        auto holePunchSettings = layerFE.prepareClientComposition(targetSettings);
        // This mimics Layer::prepareClearClientComposition
        holePunchSettings->source.buffer.buffer = nullptr;
        holePunchSettings->source.solidColor = half3(0.0f, 0.0f, 0.0f);
        holePunchSettings->disableBlending = true;
        holePunchSettings->alpha = 0.0f;
        holePunchSettings->name =
                android::base::StringPrintf("hole punch layer for %s", layerFE.getDebugName());

        // Add a solid background as the first layer in case there is no opaque
        // buffer behind the punch hole
        renderengine::LayerSettings holePunchBackgroundSettings;
        holePunchBackgroundSettings.alpha = 1.0f;
        holePunchBackgroundSettings.name = std::string("holePunchBackground");
        holePunchBackgroundSettings.geometry.boundaries = holePunchSettings->geometry.boundaries;
        holePunchBackgroundSettings.geometry.positionTransform =
                holePunchSettings->geometry.positionTransform;
        layerSettings.emplace(layerSettings.begin(), std::move(holePunchBackgroundSettings));

        layerSettings.push_back(std::move(*holePunchSettings));
    }

    if (sDebugHighlighLayers) {
        highlight = {
                .geometry =
                        renderengine::Geometry{
                                .boundaries = FloatRect(0.0f, 0.0f,
                                                        static_cast<float>(mBounds.getWidth()),
                                                        static_cast<float>(mBounds.getHeight())),
                        },
                .source =
                        renderengine::PixelSource{
                                .solidColor = half3(0.25f, 0.0f, 0.5f),
                        },
                .alpha = half(0.05f),
        };

        layerSettings.emplace_back(highlight);
    }

    auto texture = texturePool.borrowTexture();
    LOG_ALWAYS_FATAL_IF(texture->get()->getBuffer()->initCheck() != OK);

    base::unique_fd bufferFence;
    if (texture->getReadyFence()) {
        // Bail out if the buffer is not ready, because there is some pending GPU work left.
        if (texture->getReadyFence()->getStatus() != Fence::Status::Signaled) {
            return;
        }
        bufferFence.reset(texture->getReadyFence()->dup());
    }

    auto fenceResult = renderEngine
                               .drawLayers(displaySettings, layerSettings, texture->get(),
                                           std::move(bufferFence))
                               .get();

    if (fenceStatus(fenceResult) == NO_ERROR) {
        mDrawFence = std::move(fenceResult).value_or(Fence::NO_FENCE);
        mOutputSpace = outputState.framebufferSpace;
        mTexture = texture;
        mTexture->setReadyFence(mDrawFence);
        mOutputSpace.setOrientation(outputState.framebufferSpace.getOrientation());
        mOutputDataspace = outputDataspace;
        mOrientation = orientation;
        mSkipCount = 0;
    } else {
        mTexture.reset();
    }
}

bool CachedSet::requiresHolePunch() const {
    // In order for the hole punch to be beneficial, the layer must be updating
    // regularly, meaning  it should not have been merged with other layers.
    if (getLayerCount() != 1) {
        return false;
    }

    // There is no benefit to a hole punch unless the layer has a buffer.
    if (!mLayers[0].getBuffer()) {
        return false;
    }

    if (hasKnownColorShift()) {
        return false;
    }

    const auto& layerFE = mLayers[0].getState()->getOutputLayer()->getLayerFE();
    const auto* compositionState = layerFE.getCompositionState();
    if (compositionState->forceClientComposition) {
        return false;
    }

    if (compositionState->blendMode != hal::BlendMode::NONE) {
        return false;
    }

    return layerFE.hasRoundedCorners();
}

bool CachedSet::hasBlurBehind() const {
    return std::any_of(mLayers.cbegin(), mLayers.cend(),
                       [](const Layer& layer) { return layer.getState()->hasBlurBehind(); });
}

namespace {
bool contains(const Rect& outer, const Rect& inner) {
    return outer.left <= inner.left && outer.right >= inner.right && outer.top <= inner.top &&
            outer.bottom >= inner.bottom;
}
}; // namespace

void CachedSet::addHolePunchLayerIfFeasible(const CachedSet& holePunchLayer, bool isFirstLayer) {
    // Verify that this CachedSet is opaque where the hole punch layer
    // will draw.
    const Rect& holePunchBounds = holePunchLayer.getBounds();
    for (const auto& layer : mLayers) {
        // The first layer is considered opaque because nothing is behind it.
        // Note that isOpaque is always false for a layer with rounded
        // corners, even if the interior is opaque. In theory, such a layer
        // could be used for a hole punch, but this is unlikely to happen in
        // practice.
        const auto* outputLayer = layer.getState()->getOutputLayer();
        if (contains(outputLayer->getState().displayFrame, holePunchBounds) &&
            (isFirstLayer || outputLayer->getLayerFE().getCompositionState()->isOpaque)) {
            mHolePunchLayer = holePunchLayer.getFirstLayer().getState();
            return;
        }
    }
}

void CachedSet::addBackgroundBlurLayer(const CachedSet& blurLayer) {
    mBlurLayer = blurLayer.getFirstLayer().getState();
}

compositionengine::OutputLayer* CachedSet::getHolePunchLayer() const {
    return mHolePunchLayer ? mHolePunchLayer->getOutputLayer() : nullptr;
}

compositionengine::OutputLayer* CachedSet::getBlurLayer() const {
    return mBlurLayer ? mBlurLayer->getOutputLayer() : nullptr;
}

bool CachedSet::hasKnownColorShift() const {
    return std::any_of(mLayers.cbegin(), mLayers.cend(), [](const Layer& layer) {
        auto dataspace = layer.getState()->getDataspace();

        // Layers are never dimmed when rendering a cached set, meaning that we may ask HWC to
        // dim a cached set. But this means that we can never cache any HDR layers so that we
        // don't accidentally dim those layers.
        const auto hdrType = getHdrRenderType(dataspace, layer.getState()->getPixelFormat(),
                                              layer.getState()->getHdrSdrRatio());
        if (hdrType != HdrRenderType::SDR) {
            return true;
        }

        // Layers that have dimming disabled pretend that they're HDR.
        if (!layer.getState()->isDimmingEnabled()) {
            return true;
        }

        if ((dataspace & HAL_DATASPACE_STANDARD_MASK) == HAL_DATASPACE_STANDARD_BT601_625) {
            // RenderEngine does not match some DPUs, so skip
            // to avoid flickering/color differences.
            return true;
        }
        return false;
    });
}

bool CachedSet::hasProtectedLayers() const {
    return std::any_of(mLayers.cbegin(), mLayers.cend(),
                       [](const Layer& layer) { return layer.getState()->isProtected(); });
}

bool CachedSet::cachingHintExcludesLayers() const {
    const bool shouldExcludeLayers =
            std::any_of(mLayers.cbegin(), mLayers.cend(), [](const Layer& layer) {
                return layer.getState()->getCachingHint() == gui::CachingHint::Disabled;
            });

    LOG_ALWAYS_FATAL_IF(shouldExcludeLayers && getLayerCount() > 1,
                        "CachedSet is invalid: should be excluded but contains %zu layers",
                        getLayerCount());
    return shouldExcludeLayers;
}

void CachedSet::dump(std::string& result) const {
    const auto now = std::chrono::steady_clock::now();

    const auto lastUpdate =
            std::chrono::duration_cast<std::chrono::milliseconds>(now - mLastUpdate);
    base::StringAppendF(&result, "  + Fingerprint %016zx, last update %sago, age %zd\n",
                        mFingerprint, durationString(lastUpdate).c_str(), mAge);
    {
        const auto b = mTexture ? mTexture->get()->getBuffer().get() : nullptr;
        base::StringAppendF(&result, "    Override buffer: %p\n", b);
    }
    base::StringAppendF(&result, "    HolePunchLayer: %p\t%s\n", mHolePunchLayer,
                        mHolePunchLayer
                                ? mHolePunchLayer->getOutputLayer()->getLayerFE().getDebugName()
                                : "");

    if (mLayers.size() == 1) {
        base::StringAppendF(&result, "    Layer [%s]\n", mLayers[0].getName().c_str());
        if (const sp<GraphicBuffer> buffer = mLayers[0].getState()->getBuffer().promote()) {
            base::StringAppendF(&result, "    Buffer %p", buffer.get());
            base::StringAppendF(&result, "    Format %s",
                                decodePixelFormat(buffer->getPixelFormat()).c_str());
        }
        base::StringAppendF(&result, "    Protected [%s]\n",
                            mLayers[0].getState()->isProtected() ? "true" : "false");
    } else {
        result.append("    Cached set of:\n");
        for (const Layer& layer : mLayers) {
            base::StringAppendF(&result, "      Layer [%s]\n", layer.getName().c_str());
            if (const sp<GraphicBuffer> buffer = layer.getState()->getBuffer().promote()) {
                base::StringAppendF(&result, "       Buffer %p", buffer.get());
                base::StringAppendF(&result, "    Format[%s]",
                                    decodePixelFormat(buffer->getPixelFormat()).c_str());
            }
            base::StringAppendF(&result, "       Protected [%s]\n",
                                layer.getState()->isProtected() ? "true" : "false");
        }
    }

    base::StringAppendF(&result, "    Creation cost: %zd\n", getCreationCost());
    base::StringAppendF(&result, "    Display cost: %zd\n", getDisplayCost());
}

} // namespace android::compositionengine::impl::planner