/*
 * Copyright 2019 Google LLC
 *
 * Use of this source code is governed by a BSD-style license that can be
 * found in the LICENSE file.
 */

#include "src/gpu/GrTextureResolveRenderTask.h"

#include "src/gpu/GrGpu.h"
#include "src/gpu/GrMemoryPool.h"
#include "src/gpu/GrOpFlushState.h"
#include "src/gpu/GrResourceAllocator.h"
#include "src/gpu/GrTexturePriv.h"

sk_sp<GrRenderTask> GrTextureResolveRenderTask::Make(
        sk_sp<GrTextureProxy> textureProxy, GrTextureResolveFlags flags, const GrCaps& caps) {
    GrTextureProxy* textureProxyPtr = textureProxy.get();
    sk_sp<GrTextureResolveRenderTask> resolveTask(
            new GrTextureResolveRenderTask(std::move(textureProxy), flags));

    // Add the target as a dependency: We will read the existing contents of this texture while
    // generating mipmap levels and/or resolving MSAA.
    //
    // NOTE: This must be called before makeClosed.
    resolveTask->addDependency(
            textureProxyPtr, GrMipMapped::kNo, GrTextureResolveManager(nullptr), caps);
    textureProxyPtr->setLastRenderTask(resolveTask.get());

    // We only resolve the texture; nobody should try to do anything else with this opsTask.
    resolveTask->makeClosed(caps);

    if (GrTextureResolveFlags::kMipMaps & flags) {
        SkASSERT(GrMipMapped::kYes == textureProxyPtr->mipMapped());
        SkASSERT(textureProxyPtr->mipMapsAreDirty());
        textureProxyPtr->markMipMapsClean();
    }

    return resolveTask;
}

void GrTextureResolveRenderTask::gatherProxyIntervals(GrResourceAllocator* alloc) const {
    // This renderTask doesn't have "normal" ops. In this case we still need to add an interval (so
    // fEndOfOpsTaskOpIndices will remain in sync), so we create a fake op# to capture the fact that
    // we manipulate fTarget.
    alloc->addInterval(fTarget.get(), alloc->curOp(), alloc->curOp(),
                       GrResourceAllocator::ActualUse::kYes);
    alloc->incOps();
}

bool GrTextureResolveRenderTask::onExecute(GrOpFlushState* flushState) {
    GrTexture* texture = fTarget->peekTexture();
    SkASSERT(texture);

    if (GrTextureResolveFlags::kMipMaps & fResolveFlags) {
        SkASSERT(texture->texturePriv().mipMapsAreDirty());
        flushState->gpu()->regenerateMipMapLevels(texture);
    }

    return true;
}