// Copyright 2017 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#include "flutter/shell/gpu/gpu_surface_software.h"

#include <memory>
#include "lib/ftl/logging.h"

namespace shell {

GPUSurfaceSoftware::GPUSurfaceSoftware(GPUSurfaceSoftwareDelegate* delegate)
    : delegate_(delegate), weak_factory_(this) {}

GPUSurfaceSoftware::~GPUSurfaceSoftware() = default;

bool GPUSurfaceSoftware::Setup() {
  return IsValid();
}

bool GPUSurfaceSoftware::IsValid() {
  return delegate_ != nullptr;
}

std::unique_ptr<SurfaceFrame> GPUSurfaceSoftware::AcquireFrame(
    const SkISize& size) {
  if (!IsValid()) {
    return nullptr;
  }

  auto backing_store = delegate_->AcquireBackingStore(size);

  if (backing_store == nullptr) {
    return nullptr;
  }

  if (size != SkISize::Make(backing_store->width(), backing_store->height())) {
    return nullptr;
  }

  SurfaceFrame::SubmitCallback
      on_submit = [self = weak_factory_.GetWeakPtr()](
                      const SurfaceFrame& surface_frame, SkCanvas* canvas)
                      ->bool {
    // If the surface itself went away, there is nothing more to do.
    if (!self || !self->IsValid() || canvas == nullptr) {
      return false;
    }

    canvas->flush();

    return self->delegate_->PresentBackingStore(surface_frame.SkiaSurface());
  };

  return std::make_unique<SurfaceFrame>(backing_store, on_submit);
}

GrContext* GPUSurfaceSoftware::GetContext() {
  // The is no GrContext associated with a software surface.
  return nullptr;
}

}  // namespace shell