Scheduler.h

/*
 * Copyright (c) Facebook, Inc. and its affiliates.
 *
 * This source code is licensed under the MIT license found in the
 * LICENSE file in the root directory of this source tree.
 */

#pragma once

#include <memory>
#include <mutex>

#include <react/components/root/RootComponentDescriptor.h>
#include <react/config/ReactNativeConfig.h>
#include <react/core/ComponentDescriptor.h>
#include <react/core/LayoutConstraints.h>
#include <react/uimanager/ComponentDescriptorFactory.h>
#include <react/uimanager/ComponentDescriptorRegistry.h>
#include <react/uimanager/SchedulerDelegate.h>
#include <react/uimanager/SchedulerToolbox.h>
#include <react/uimanager/UIManagerBinding.h>
#include <react/uimanager/UIManagerDelegate.h>
#include <react/utils/ContextContainer.h>
#include <react/utils/RuntimeExecutor.h>

namespace facebook {
namespace react {

/*
 * Scheduler coordinates Shadow Tree updates and event flows.
 */
class Scheduler final : public UIManagerDelegate {
 public:
  Scheduler(SchedulerToolbox schedulerToolbox, SchedulerDelegate *delegate);
  ~Scheduler();

#pragma mark - Surface Management

  void startSurface(
      SurfaceId surfaceId,
      const std::string &moduleName,
      const folly::dynamic &initialProps,
      const LayoutConstraints &layoutConstraints = {},
      const LayoutContext &layoutContext = {}) const;

  void renderTemplateToSurface(
      SurfaceId surfaceId,
      const std::string &uiTemplate);

  void stopSurface(SurfaceId surfaceId) const;

  Size measureSurface(
      SurfaceId surfaceId,
      const LayoutConstraints &layoutConstraints,
      const LayoutContext &layoutContext) const;

  /*
   * Applies given `layoutConstraints` and `layoutContext` to a Surface.
   * The user interface will be relaid out as a result. The operation will be
   * performed synchronously (including mounting) if the method is called
   * on the main thread.
   * Can be called from any thread.
   */
  void constraintSurfaceLayout(
      SurfaceId surfaceId,
      const LayoutConstraints &layoutConstraints,
      const LayoutContext &layoutContext) const;

  /*
   * This is broken. Please do not use.
   * `ComponentDescriptor`s are not designed to be used outside of `UIManager`,
   * there is no any garantees about their lifetime.
   */
  ComponentDescriptor const *
  findComponentDescriptorByHandle_DO_NOT_USE_THIS_IS_BROKEN(
      ComponentHandle handle) const;

  MountingCoordinator::Shared findMountingCoordinator(
      SurfaceId surfaceId) const;

#pragma mark - Delegate

  /*
   * Sets and gets the Scheduler's delegate.
   * If you requesting a ComponentDescriptor and unsure that it's there, you are
   * doing something wrong.
   */
  void setDelegate(SchedulerDelegate *delegate);
  SchedulerDelegate *getDelegate() const;

#pragma mark - UIManagerDelegate

  void uiManagerDidFinishTransaction(
      MountingCoordinator::Shared const &mountingCoordinator) override;
  void uiManagerDidCreateShadowNode(
      const ShadowNode::Shared &shadowNode) override;
  void uiManagerDidDispatchCommand(
      const ShadowNode::Shared &shadowNode,
      std::string const &commandName,
      folly::dynamic const args) override;
  void uiManagerDidSetJSResponder(
      SurfaceId surfaceId,
      const ShadowNode::Shared &shadowView,
      bool blockNativeResponder) override;
  void uiManagerDidClearJSResponder() override;

 private:
  SchedulerDelegate *delegate_;
  SharedComponentDescriptorRegistry componentDescriptorRegistry_;
  std::unique_ptr<const RootComponentDescriptor> rootComponentDescriptor_;
  RuntimeExecutor runtimeExecutor_;
  std::shared_ptr<UIManager> uiManager_;
  std::shared_ptr<const ReactNativeConfig> reactNativeConfig_;
  EventDispatcher::Shared eventDispatcher_;
};

} // namespace react
} // namespace facebook