/*
 * Copyright (C) 2016 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.
 */

#include "SkiaOpenGLPipeline.h"

#include "DeferredLayerUpdater.h"
#include "GlLayer.h"
#include "LayerDrawable.h"
#include "renderthread/EglManager.h"
#include "renderthread/Frame.h"
#include "renderstate/RenderState.h"
#include "SkiaPipeline.h"
#include "SkiaProfileRenderer.h"
#include "utils/TraceUtils.h"

#include <cutils/properties.h>
#include <strings.h>
#include <SkImagePriv.h>
#include <gl/GrGLTypes.h>

using namespace android::uirenderer::renderthread;

namespace android {
namespace uirenderer {
namespace skiapipeline {

SkiaOpenGLPipeline::SkiaOpenGLPipeline(RenderThread& thread)
        : SkiaPipeline(thread)
        , mEglManager(thread.eglManager()) {
}

MakeCurrentResult SkiaOpenGLPipeline::makeCurrent() {
    // TODO: Figure out why this workaround is needed, see b/13913604
    // In the meantime this matches the behavior of GLRenderer, so it is not a regression
    EGLint error = 0;
    if (!mEglManager.makeCurrent(mEglSurface, &error)) {
        return MakeCurrentResult::AlreadyCurrent;
    }
    return error ? MakeCurrentResult::Failed : MakeCurrentResult::Succeeded;
}

Frame SkiaOpenGLPipeline::getFrame() {
    LOG_ALWAYS_FATAL_IF(mEglSurface == EGL_NO_SURFACE,
                "drawRenderNode called on a context with no surface!");
    return mEglManager.beginFrame(mEglSurface);
}

bool SkiaOpenGLPipeline::draw(const Frame& frame, const SkRect& screenDirty,
        const SkRect& dirty,
        const FrameBuilder::LightGeometry& lightGeometry,
        LayerUpdateQueue* layerUpdateQueue,
        const Rect& contentDrawBounds, bool opaque,
        const BakedOpRenderer::LightInfo& lightInfo,
        const std::vector<sp<RenderNode>>& renderNodes,
        FrameInfoVisualizer* profiler) {

    mEglManager.damageFrame(frame, dirty);

    // setup surface for fbo0
    GrBackendRenderTargetDesc renderTargetDesc;
    renderTargetDesc.fWidth = frame.width();
    renderTargetDesc.fHeight = frame.height();
    renderTargetDesc.fConfig = kRGBA_8888_GrPixelConfig;
    renderTargetDesc.fOrigin = kBottomLeft_GrSurfaceOrigin;
    renderTargetDesc.fSampleCnt = 0;
    renderTargetDesc.fStencilBits = STENCIL_BUFFER_SIZE;
    renderTargetDesc.fRenderTargetHandle = 0;

    SkSurfaceProps props(0, kUnknown_SkPixelGeometry);

    SkASSERT(mRenderThread.getGrContext() != nullptr);
    sk_sp<SkSurface> surface(SkSurface::MakeFromBackendRenderTarget(
            mRenderThread.getGrContext(), renderTargetDesc, &props));

    SkiaPipeline::updateLighting(lightGeometry, lightInfo);
    renderFrame(*layerUpdateQueue, dirty, renderNodes, opaque, contentDrawBounds, surface);
    layerUpdateQueue->clear();

    // Draw visual debugging features
    if (CC_UNLIKELY(Properties::showDirtyRegions
            || ProfileType::None != Properties::getProfileType())) {
        SkCanvas* profileCanvas = surface->getCanvas();
        SkiaProfileRenderer profileRenderer(profileCanvas);
        profiler->draw(profileRenderer);
        profileCanvas->flush();
    }

    // Log memory statistics
    if (CC_UNLIKELY(Properties::debugLevel != kDebugDisabled)) {
        dumpResourceCacheUsage();
    }

    return true;
}

bool SkiaOpenGLPipeline::swapBuffers(const Frame& frame, bool drew,
        const SkRect& screenDirty, FrameInfo* currentFrameInfo, bool* requireSwap) {

    GL_CHECKPOINT(LOW);

    // Even if we decided to cancel the frame, from the perspective of jank
    // metrics the frame was swapped at this point
    currentFrameInfo->markSwapBuffers();

    *requireSwap = drew || mEglManager.damageRequiresSwap();

    if (*requireSwap && (CC_UNLIKELY(!mEglManager.swapBuffers(frame, screenDirty)))) {
        return false;
    }

    return *requireSwap;
}

bool SkiaOpenGLPipeline::copyLayerInto(DeferredLayerUpdater* deferredLayer, SkBitmap* bitmap) {
    if (!mRenderThread.getGrContext()) {
        return false;
    }

    // acquire most recent buffer for drawing
    deferredLayer->updateTexImage();
    deferredLayer->apply();

    SkCanvas canvas(*bitmap);
    Layer* layer = deferredLayer->backingLayer();
    return LayerDrawable::DrawLayer(mRenderThread.getGrContext(), &canvas, layer);
}

static Layer* createLayer(RenderState& renderState, uint32_t layerWidth, uint32_t layerHeight,
        SkColorFilter* colorFilter, int alpha, SkBlendMode mode, bool blend) {
    GlLayer* layer = new GlLayer(renderState, layerWidth, layerHeight, colorFilter, alpha,
            mode, blend);
    layer->generateTexture();
    return layer;
}

DeferredLayerUpdater* SkiaOpenGLPipeline::createTextureLayer() {
    mEglManager.initialize();
    return new DeferredLayerUpdater(mRenderThread.renderState(), createLayer, Layer::Api::OpenGL);
}

void SkiaOpenGLPipeline::onStop() {
    if (mEglManager.isCurrent(mEglSurface)) {
        mEglManager.makeCurrent(EGL_NO_SURFACE);
    }
}

bool SkiaOpenGLPipeline::setSurface(Surface* surface, SwapBehavior swapBehavior) {

    if (mEglSurface != EGL_NO_SURFACE) {
        mEglManager.destroySurface(mEglSurface);
        mEglSurface = EGL_NO_SURFACE;
    }

    if (surface) {
        mEglSurface = mEglManager.createSurface(surface);
    }

    if (mEglSurface != EGL_NO_SURFACE) {
        const bool preserveBuffer = (swapBehavior != SwapBehavior::kSwap_discardBuffer);
        mBufferPreserved = mEglManager.setPreserveBuffer(mEglSurface, preserveBuffer);
        return true;
    }

    return false;
}

bool SkiaOpenGLPipeline::isSurfaceReady() {
    return CC_UNLIKELY(mEglSurface != EGL_NO_SURFACE);
}

bool SkiaOpenGLPipeline::isContextReady() {
    return CC_LIKELY(mEglManager.hasEglContext());
}

void SkiaOpenGLPipeline::invokeFunctor(const RenderThread& thread, Functor* functor) {
    DrawGlInfo::Mode mode = DrawGlInfo::kModeProcessNoContext;
    if (thread.eglManager().hasEglContext()) {
        mode = DrawGlInfo::kModeProcess;
    }

    (*functor)(mode, nullptr);

    // If there's no context we don't need to reset as there's no gl state to save/restore
    if (mode != DrawGlInfo::kModeProcessNoContext) {
        thread.getGrContext()->resetContext();
    }
}

static void deleteImageTexture(void* context) {
     EGLImageKHR EGLimage = reinterpret_cast<EGLImageKHR>(context);
     if (EGLimage != EGL_NO_IMAGE_KHR) {
        EGLDisplay display = eglGetCurrentDisplay();
        if (EGL_NO_DISPLAY == display) {
            display = eglGetDisplay(EGL_DEFAULT_DISPLAY);
        }
        eglDestroyImageKHR(display, EGLimage);
     }
}

sk_sp<SkImage> SkiaOpenGLPipeline::makeTextureImage(
        const uirenderer::renderthread::RenderThread& renderThread, Bitmap* bitmap) {
    renderThread.eglManager().initialize();

    GraphicBuffer* buffer = bitmap->graphicBuffer();
    EGLDisplay display = eglGetCurrentDisplay();
    if (EGL_NO_DISPLAY == display) {
        display = eglGetDisplay(EGL_DEFAULT_DISPLAY);
    }
    LOG_ALWAYS_FATAL_IF(!bitmap->isHardware(),
                "Texture image requires a HW bitmap.");
    // We use an EGLImage to access the content of the GraphicBuffer
    // The EGL image is later bound to a 2D texture
    EGLClientBuffer clientBuffer = (EGLClientBuffer) buffer->getNativeBuffer();
    EGLint imageAttrs[] = { EGL_IMAGE_PRESERVED_KHR, EGL_TRUE, EGL_NONE };
    EGLImageKHR EGLimage = eglCreateImageKHR(display, EGL_NO_CONTEXT, EGL_NATIVE_BUFFER_ANDROID,
            clientBuffer, imageAttrs);
    if (EGLimage == EGL_NO_IMAGE_KHR) {
        ALOGW("Could not create EGL image, err =%s",
                uirenderer::renderthread::EglManager::eglErrorString());
        return nullptr;
    }

    GLuint textureId = 0;
    glGenTextures(1, &textureId);
    glBindTexture(GL_TEXTURE_EXTERNAL_OES, textureId);
    glEGLImageTargetTexture2DOES(GL_TEXTURE_EXTERNAL_OES, EGLimage);

    GLenum status = GL_NO_ERROR;
    while ((status = glGetError()) != GL_NO_ERROR) {
        ALOGW("glEGLImageTargetTexture2DOES failed (%#x)", status);
        eglDestroyImageKHR(display, EGLimage);
        return nullptr;
    }

    sk_sp<GrContext> grContext = sk_ref_sp(renderThread.getGrContext());
    grContext->resetContext();

    GrGLTextureInfo textureInfo;
    textureInfo.fTarget = GL_TEXTURE_EXTERNAL_OES;
    textureInfo.fID = textureId;

    GrBackendTextureDesc textureDescription;
    textureDescription.fWidth = bitmap->info().width();
    textureDescription.fHeight = bitmap->info().height();
    textureDescription.fOrigin = kTopLeft_GrSurfaceOrigin;
    textureDescription.fTextureHandle = reinterpret_cast<GrBackendObject>(&textureInfo);
    PixelFormat format = buffer->getPixelFormat();
    switch (format) {
    case PIXEL_FORMAT_RGBA_8888:
        textureDescription.fConfig = kRGBA_8888_GrPixelConfig;
        break;
    case PIXEL_FORMAT_RGBA_FP16:
        textureDescription.fConfig = kRGBA_half_GrPixelConfig;
        break;
    default:
        eglDestroyImageKHR(display, EGLimage);
        return nullptr;
    }

    // TODO: add color correctness - pass null color space for now
    sk_sp<SkImage> image = SkImage::MakeFromTexture(grContext.get(), textureDescription,
                bitmap->info().alphaType(), nullptr, deleteImageTexture, EGLimage);
    if (!image.get()) {
        eglDestroyImageKHR(display, EGLimage);
        return nullptr;
    }
    return image;
}

} /* namespace skiapipeline */
} /* namespace uirenderer */
} /* namespace android */