shell/common/engine.cc - mirrors/engine - Git at Google

 // Copyright 2013 The Flutter 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/common/engine.h"

 #include <memory>
 #include <string>
 #include <utility>
 #include <vector>

 #include "flutter/common/settings.h"
 #include "flutter/fml/eintr_wrapper.h"
 #include "flutter/fml/file.h"
 #include "flutter/fml/make_copyable.h"
 #include "flutter/fml/paths.h"
 #include "flutter/fml/trace_event.h"
 #include "flutter/fml/unique_fd.h"
 #include "flutter/lib/snapshot/snapshot.h"
 #include "flutter/lib/ui/text/font_collection.h"
 #include "flutter/shell/common/animator.h"
 #include "flutter/shell/common/platform_view.h"
 #include "flutter/shell/common/shell.h"
 #include "rapidjson/document.h"
 #include "third_party/dart/runtime/include/dart_tools_api.h"
 #include "third_party/skia/include/core/SkCanvas.h"
 #include "third_party/skia/include/core/SkPictureRecorder.h"

 namespace flutter {

 static constexpr char kAssetChannel[] = "flutter/assets";
 static constexpr char kLifecycleChannel[] = "flutter/lifecycle";
 static constexpr char kNavigationChannel[] = "flutter/navigation";
 static constexpr char kLocalizationChannel[] = "flutter/localization";
 static constexpr char kSettingsChannel[] = "flutter/settings";
 static constexpr char kIsolateChannel[] = "flutter/isolate";

 Engine::Engine(
     Delegate& delegate,
     const PointerDataDispatcherMaker& dispatcher_maker,
     std::shared_ptr<fml::ConcurrentTaskRunner> image_decoder_task_runner,
     TaskRunners task_runners,
     Settings settings,
     std::unique_ptr<Animator> animator,
     fml::WeakPtr<IOManager> io_manager,
     const std::shared_ptr<FontCollection>& font_collection,
     std::unique_ptr<RuntimeController> runtime_controller)
     : delegate_(delegate),
       settings_(std::move(settings)),
       animator_(std::move(animator)),
       runtime_controller_(std::move(runtime_controller)),
       activity_running_(true),
       have_surface_(false),
       font_collection_(font_collection),
       image_decoder_(task_runners, image_decoder_task_runner, io_manager),
       task_runners_(std::move(task_runners)),
       weak_factory_(this) {
   pointer_data_dispatcher_ = dispatcher_maker(*this);
 }

 Engine::Engine(Delegate& delegate,
                const PointerDataDispatcherMaker& dispatcher_maker,
                DartVM& vm,
                fml::RefPtr<const DartSnapshot> isolate_snapshot,
                TaskRunners task_runners,
                const PlatformData& platform_data,
                Settings settings,
                std::unique_ptr<Animator> animator,
                fml::WeakPtr<IOManager> io_manager,
                fml::RefPtr<SkiaUnrefQueue> unref_queue,
                fml::WeakPtr<SnapshotDelegate> snapshot_delegate,
                std::shared_ptr<VolatilePathTracker> volatile_path_tracker)
     : Engine(delegate,
              dispatcher_maker,
              vm.GetConcurrentWorkerTaskRunner(),
              task_runners,
              settings,
              std::move(animator),
              io_manager,
              std::make_shared<FontCollection>(),
              nullptr) {
   runtime_controller_ = std::make_unique<RuntimeController>(
       *this,                                 // runtime delegate
       &vm,                                   // VM
       std::move(isolate_snapshot),           // isolate snapshot
       task_runners_,                         // task runners
       std::move(snapshot_delegate),          // snapshot delegate
       GetWeakPtr(),                          // hint freed delegate
       std::move(io_manager),                 // io manager
       std::move(unref_queue),                // Skia unref queue
       image_decoder_.GetWeakPtr(),           // image decoder
       settings_.advisory_script_uri,         // advisory script uri
       settings_.advisory_script_entrypoint,  // advisory script entrypoint
       settings_.idle_notification_callback,  // idle notification callback
       platform_data,                         // platform data
       settings_.isolate_create_callback,     // isolate create callback
       settings_.isolate_shutdown_callback,   // isolate shutdown callback
       settings_.persistent_isolate_data,     // persistent isolate data
       std::move(volatile_path_tracker)       // volatile path tracker
   );
 }

 std::unique_ptr<Engine> Engine::Spawn(
     Delegate& delegate,
     const PointerDataDispatcherMaker& dispatcher_maker,
     Settings settings,
     std::unique_ptr<Animator> animator) const {
   auto result = std::make_unique<Engine>(
       /*delegate=*/delegate,
       /*dispatcher_maker=*/dispatcher_maker,
       /*image_decoder_task_runner=*/
       runtime_controller_->GetDartVM()->GetConcurrentWorkerTaskRunner(),
       /*task_runners=*/task_runners_,
       /*settings=*/settings,
       /*animator=*/std::move(animator),
       /*io_manager=*/runtime_controller_->GetIOManager(),
       /*font_collection=*/font_collection_,
       /*runtime_controller=*/nullptr);
   result->runtime_controller_ = runtime_controller_->Spawn(
       *result,                               // runtime delegate
       settings_.advisory_script_uri,         // advisory script uri
       settings_.advisory_script_entrypoint,  // advisory script entrypoint
       settings_.idle_notification_callback,  // idle notification callback
       settings_.isolate_create_callback,     // isolate create callback
       settings_.isolate_shutdown_callback,   // isolate shutdown callback
       settings_.persistent_isolate_data      // persistent isolate data
   );
   return result;
 }

 Engine::~Engine() = default;

 fml::WeakPtr<Engine> Engine::GetWeakPtr() const {
   return weak_factory_.GetWeakPtr();
 }

 void Engine::SetupDefaultFontManager() {
   TRACE_EVENT0("flutter", "Engine::SetupDefaultFontManager");
   font_collection_->SetupDefaultFontManager();
 }

 std::shared_ptr<AssetManager> Engine::GetAssetManager() {
   return asset_manager_;
 }

 bool Engine::UpdateAssetManager(
     std::shared_ptr<AssetManager> new_asset_manager) {
   if (asset_manager_ == new_asset_manager) {
     return false;
   }

   asset_manager_ = new_asset_manager;

   if (!asset_manager_) {
     return false;
   }

   // Using libTXT as the text engine.
   font_collection_->RegisterFonts(asset_manager_);

   if (settings_.use_test_fonts) {
     font_collection_->RegisterTestFonts();
   }

   return true;
 }

 bool Engine::Restart(RunConfiguration configuration) {
   TRACE_EVENT0("flutter", "Engine::Restart");
   if (!configuration.IsValid()) {
     FML_LOG(ERROR) << "Engine run configuration was invalid.";
     return false;
   }
   delegate_.OnPreEngineRestart();
   runtime_controller_ = runtime_controller_->Clone();
   UpdateAssetManager(nullptr);
   return Run(std::move(configuration)) == Engine::RunStatus::Success;
 }

 Engine::RunStatus Engine::Run(RunConfiguration configuration) {
   if (!configuration.IsValid()) {
     FML_LOG(ERROR) << "Engine run configuration was invalid.";
     return RunStatus::Failure;
   }

   last_entry_point_ = configuration.GetEntrypoint();
   last_entry_point_library_ = configuration.GetEntrypointLibrary();

   UpdateAssetManager(configuration.GetAssetManager());

   if (runtime_controller_->IsRootIsolateRunning()) {
     return RunStatus::FailureAlreadyRunning;
   }

   if (!runtime_controller_->LaunchRootIsolate(
           settings_,                                 //
           configuration.GetEntrypoint(),             //
           configuration.GetEntrypointLibrary(),      //
           configuration.TakeIsolateConfiguration())  //
   ) {
     return RunStatus::Failure;
   }

   auto service_id = runtime_controller_->GetRootIsolateServiceID();
   if (service_id.has_value()) {
     fml::RefPtr<PlatformMessage> service_id_message =
         fml::MakeRefCounted<flutter::PlatformMessage>(
             kIsolateChannel,
             std::vector<uint8_t>(service_id.value().begin(),
                                  service_id.value().end()),
             nullptr);
     HandlePlatformMessage(service_id_message);
   }

   return Engine::RunStatus::Success;
 }

 void Engine::BeginFrame(fml::TimePoint frame_time) {
   TRACE_EVENT0("flutter", "Engine::BeginFrame");
   runtime_controller_->BeginFrame(frame_time);
 }

 void Engine::ReportTimings(std::vector<int64_t> timings) {
   TRACE_EVENT0("flutter", "Engine::ReportTimings");
   runtime_controller_->ReportTimings(std::move(timings));
 }

 void Engine::HintFreed(size_t size) {
   hint_freed_bytes_since_last_idle_ += size;
 }

 void Engine::NotifyIdle(int64_t deadline) {
   auto trace_event = std::to_string(deadline - Dart_TimelineGetMicros());
   TRACE_EVENT1("flutter", "Engine::NotifyIdle", "deadline_now_delta",
                trace_event.c_str());
   runtime_controller_->NotifyIdle(deadline, hint_freed_bytes_since_last_idle_);
   hint_freed_bytes_since_last_idle_ = 0;
 }

 std::optional<uint32_t> Engine::GetUIIsolateReturnCode() {
   return runtime_controller_->GetRootIsolateReturnCode();
 }

 Dart_Port Engine::GetUIIsolateMainPort() {
   return runtime_controller_->GetMainPort();
 }

 std::string Engine::GetUIIsolateName() {
   return runtime_controller_->GetIsolateName();
 }

 bool Engine::UIIsolateHasLivePorts() {
   return runtime_controller_->HasLivePorts();
 }

 tonic::DartErrorHandleType Engine::GetUIIsolateLastError() {
   return runtime_controller_->GetLastError();
 }

 void Engine::OnOutputSurfaceCreated() {
   have_surface_ = true;
   StartAnimatorIfPossible();
   ScheduleFrame();
 }

 void Engine::OnOutputSurfaceDestroyed() {
   have_surface_ = false;
   StopAnimator();
 }

 void Engine::SetViewportMetrics(const ViewportMetrics& metrics) {
   bool dimensions_changed =
       viewport_metrics_.physical_height != metrics.physical_height ||
       viewport_metrics_.physical_width != metrics.physical_width ||
       viewport_metrics_.device_pixel_ratio != metrics.device_pixel_ratio;
   viewport_metrics_ = metrics;
   runtime_controller_->SetViewportMetrics(viewport_metrics_);
   if (animator_) {
     if (dimensions_changed) {
       animator_->SetDimensionChangePending();
     }
     if (have_surface_) {
       ScheduleFrame();
     }
   }
 }

 void Engine::DispatchPlatformMessage(fml::RefPtr<PlatformMessage> message) {
   std::string channel = message->channel();
   if (channel == kLifecycleChannel) {
     if (HandleLifecyclePlatformMessage(message.get())) {
       return;
     }
   } else if (channel == kLocalizationChannel) {
     if (HandleLocalizationPlatformMessage(message.get())) {
       return;
     }
   } else if (channel == kSettingsChannel) {
     HandleSettingsPlatformMessage(message.get());
     return;
   } else if (!runtime_controller_->IsRootIsolateRunning() &&
              channel == kNavigationChannel) {
     // If there's no runtime_, we may still need to set the initial route.
     HandleNavigationPlatformMessage(std::move(message));
     return;
   }

   if (runtime_controller_->IsRootIsolateRunning() &&
       runtime_controller_->DispatchPlatformMessage(std::move(message))) {
     return;
   }

   FML_DLOG(WARNING) << "Dropping platform message on channel: " << channel;
 }

 bool Engine::HandleLifecyclePlatformMessage(PlatformMessage* message) {
   const auto& data = message->data();
   std::string state(reinterpret_cast<const char*>(data.data()), data.size());
   if (state == "AppLifecycleState.paused" ||
       state == "AppLifecycleState.detached") {
     activity_running_ = false;
     StopAnimator();
   } else if (state == "AppLifecycleState.resumed" ||
              state == "AppLifecycleState.inactive") {
     activity_running_ = true;
     StartAnimatorIfPossible();
   }

   // Always schedule a frame when the app does become active as per API
   // recommendation
   // https://developer.apple.com/documentation/uikit/uiapplicationdelegate/1622956-applicationdidbecomeactive?language=objc
   if (state == "AppLifecycleState.resumed" && have_surface_) {
     ScheduleFrame();
   }
   runtime_controller_->SetLifecycleState(state);
   // Always forward these messages to the framework by returning false.
   return false;
 }

 bool Engine::HandleNavigationPlatformMessage(
     fml::RefPtr<PlatformMessage> message) {
   const auto& data = message->data();

   rapidjson::Document document;
   document.Parse(reinterpret_cast<const char*>(data.data()), data.size());
   if (document.HasParseError() || !document.IsObject()) {
     return false;
   }
   auto root = document.GetObject();
   auto method = root.FindMember("method");
   if (method->value != "setInitialRoute") {
     return false;
   }
   auto route = root.FindMember("args");
   initial_route_ = std::move(route->value.GetString());
   return true;
 }

 bool Engine::HandleLocalizationPlatformMessage(PlatformMessage* message) {
   const auto& data = message->data();

   rapidjson::Document document;
   document.Parse(reinterpret_cast<const char*>(data.data()), data.size());
   if (document.HasParseError() || !document.IsObject()) {
     return false;
   }
   auto root = document.GetObject();
   auto method = root.FindMember("method");
   if (method == root.MemberEnd()) {
     return false;
   }
   const size_t strings_per_locale = 4;
   if (method->value == "setLocale") {
     // Decode and pass the list of locale data onwards to dart.
     auto args = root.FindMember("args");
     if (args == root.MemberEnd() || !args->value.IsArray()) {
       return false;
     }

     if (args->value.Size() % strings_per_locale != 0) {
       return false;
     }
     std::vector<std::string> locale_data;
     for (size_t locale_index = 0; locale_index < args->value.Size();
          locale_index += strings_per_locale) {
       if (!args->value[locale_index].IsString() ||
           !args->value[locale_index + 1].IsString()) {
         return false;
       }
       locale_data.push_back(args->value[locale_index].GetString());
       locale_data.push_back(args->value[locale_index + 1].GetString());
       locale_data.push_back(args->value[locale_index + 2].GetString());
       locale_data.push_back(args->value[locale_index + 3].GetString());
     }

     return runtime_controller_->SetLocales(locale_data);
   }
   return false;
 }

 void Engine::HandleSettingsPlatformMessage(PlatformMessage* message) {
   const auto& data = message->data();
   std::string jsonData(reinterpret_cast<const char*>(data.data()), data.size());
   if (runtime_controller_->SetUserSettingsData(std::move(jsonData)) &&
       have_surface_) {
     ScheduleFrame();
   }
 }

 void Engine::DispatchPointerDataPacket(
     std::unique_ptr<PointerDataPacket> packet,
     uint64_t trace_flow_id) {
   TRACE_EVENT0("flutter", "Engine::DispatchPointerDataPacket");
   TRACE_FLOW_STEP("flutter", "PointerEvent", trace_flow_id);
   pointer_data_dispatcher_->DispatchPacket(std::move(packet), trace_flow_id);
 }

 void Engine::DispatchKeyDataPacket(std::unique_ptr<KeyDataPacket> packet,
                                    KeyDataResponse callback) {
   TRACE_EVENT0("flutter", "Engine::DispatchKeyDataPacket");
   if (runtime_controller_) {
     runtime_controller_->DispatchKeyDataPacket(*packet, std::move(callback));
   }
 }

 void Engine::DispatchSemanticsAction(int id,
                                      SemanticsAction action,
                                      std::vector<uint8_t> args) {
   runtime_controller_->DispatchSemanticsAction(id, action, std::move(args));
 }

 void Engine::SetSemanticsEnabled(bool enabled) {
   runtime_controller_->SetSemanticsEnabled(enabled);
 }

 void Engine::SetAccessibilityFeatures(int32_t flags) {
   runtime_controller_->SetAccessibilityFeatures(flags);
 }

 void Engine::StopAnimator() {
   animator_->Stop();
 }

 void Engine::StartAnimatorIfPossible() {
   if (activity_running_ && have_surface_) {
     animator_->Start();
   }
 }

 std::string Engine::DefaultRouteName() {
   if (!initial_route_.empty()) {
     return initial_route_;
   }
   return "/";
 }

 void Engine::ScheduleFrame(bool regenerate_layer_tree) {
   animator_->RequestFrame(regenerate_layer_tree);
 }

 void Engine::Render(std::unique_ptr<flutter::LayerTree> layer_tree) {
   if (!layer_tree) {
     return;
   }

   // Ensure frame dimensions are sane.
   if (layer_tree->frame_size().isEmpty() ||
       layer_tree->device_pixel_ratio() <= 0.0f) {
     return;
   }

   animator_->Render(std::move(layer_tree));
 }

 void Engine::UpdateSemantics(SemanticsNodeUpdates update,
                              CustomAccessibilityActionUpdates actions) {
   delegate_.OnEngineUpdateSemantics(std::move(update), std::move(actions));
 }

 void Engine::HandlePlatformMessage(fml::RefPtr<PlatformMessage> message) {
   if (message->channel() == kAssetChannel) {
     HandleAssetPlatformMessage(std::move(message));
   } else {
     delegate_.OnEngineHandlePlatformMessage(std::move(message));
   }
 }

 void Engine::OnRootIsolateCreated() {
   delegate_.OnRootIsolateCreated();
 }

 void Engine::UpdateIsolateDescription(const std::string isolate_name,
                                       int64_t isolate_port) {
   delegate_.UpdateIsolateDescription(isolate_name, isolate_port);
 }

 std::unique_ptr<std::vector<std::string>> Engine::ComputePlatformResolvedLocale(
     const std::vector<std::string>& supported_locale_data) {
   return delegate_.ComputePlatformResolvedLocale(supported_locale_data);
 }

 void Engine::SetNeedsReportTimings(bool needs_reporting) {
   delegate_.SetNeedsReportTimings(needs_reporting);
 }

 FontCollection& Engine::GetFontCollection() {
   return *font_collection_;
 }

 void Engine::DoDispatchPacket(std::unique_ptr<PointerDataPacket> packet,
                               uint64_t trace_flow_id) {
   animator_->EnqueueTraceFlowId(trace_flow_id);
   if (runtime_controller_) {
     runtime_controller_->DispatchPointerDataPacket(*packet);
   }
 }

 void Engine::ScheduleSecondaryVsyncCallback(uintptr_t id,
                                             const fml::closure& callback) {
   animator_->ScheduleSecondaryVsyncCallback(id, callback);
 }

 void Engine::HandleAssetPlatformMessage(fml::RefPtr<PlatformMessage> message) {
   fml::RefPtr<PlatformMessageResponse> response = message->response();
   if (!response) {
     return;
   }
   const auto& data = message->data();
   std::string asset_name(reinterpret_cast<const char*>(data.data()),
                          data.size());

   if (asset_manager_) {
     std::unique_ptr<fml::Mapping> asset_mapping =
         asset_manager_->GetAsMapping(asset_name);
     if (asset_mapping) {
       response->Complete(std::move(asset_mapping));
       return;
     }
   }

   response->CompleteEmpty();
 }

 const std::string& Engine::GetLastEntrypoint() const {
   return last_entry_point_;
 }

 const std::string& Engine::GetLastEntrypointLibrary() const {
   return last_entry_point_library_;
 }

 // |RuntimeDelegate|
 void Engine::RequestDartDeferredLibrary(intptr_t loading_unit_id) {
   return delegate_.RequestDartDeferredLibrary(loading_unit_id);
 }

 void Engine::LoadDartDeferredLibrary(
     intptr_t loading_unit_id,
     std::unique_ptr<const fml::Mapping> snapshot_data,
     std::unique_ptr<const fml::Mapping> snapshot_instructions) {
   if (runtime_controller_->IsRootIsolateRunning()) {
     runtime_controller_->LoadDartDeferredLibrary(
         loading_unit_id, std::move(snapshot_data),
         std::move(snapshot_instructions));
   } else {
     LoadDartDeferredLibraryError(loading_unit_id, "No running root isolate.",
                                  true);
   }
 }

 void Engine::LoadDartDeferredLibraryError(intptr_t loading_unit_id,
                                           const std::string error_message,
                                           bool transient) {
   if (runtime_controller_->IsRootIsolateRunning()) {
     runtime_controller_->LoadDartDeferredLibraryError(loading_unit_id,
                                                       error_message, transient);
   }
 }

 }  // namespace flutter
	// Copyright 2013 The Flutter 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/common/engine.h"

	#include <memory>
	#include <string>
	#include <utility>
	#include <vector>

	#include "flutter/common/settings.h"
	#include "flutter/fml/eintr_wrapper.h"
	#include "flutter/fml/file.h"
	#include "flutter/fml/make_copyable.h"
	#include "flutter/fml/paths.h"
	#include "flutter/fml/trace_event.h"
	#include "flutter/fml/unique_fd.h"
	#include "flutter/lib/snapshot/snapshot.h"
	#include "flutter/lib/ui/text/font_collection.h"
	#include "flutter/shell/common/animator.h"
	#include "flutter/shell/common/platform_view.h"
	#include "flutter/shell/common/shell.h"
	#include "rapidjson/document.h"
	#include "third_party/dart/runtime/include/dart_tools_api.h"
	#include "third_party/skia/include/core/SkCanvas.h"
	#include "third_party/skia/include/core/SkPictureRecorder.h"

	namespace flutter {

	static constexpr char kAssetChannel[] = "flutter/assets";
	static constexpr char kLifecycleChannel[] = "flutter/lifecycle";
	static constexpr char kNavigationChannel[] = "flutter/navigation";
	static constexpr char kLocalizationChannel[] = "flutter/localization";
	static constexpr char kSettingsChannel[] = "flutter/settings";
	static constexpr char kIsolateChannel[] = "flutter/isolate";

	Engine::Engine(
	Delegate& delegate,
	const PointerDataDispatcherMaker& dispatcher_maker,
	std::shared_ptr<fml::ConcurrentTaskRunner> image_decoder_task_runner,
	TaskRunners task_runners,
	Settings settings,
	std::unique_ptr<Animator> animator,
	fml::WeakPtr<IOManager> io_manager,
	const std::shared_ptr<FontCollection>& font_collection,
	std::unique_ptr<RuntimeController> runtime_controller)
	: delegate_(delegate),
	settings_(std::move(settings)),
	animator_(std::move(animator)),
	runtime_controller_(std::move(runtime_controller)),
	activity_running_(true),
	have_surface_(false),
	font_collection_(font_collection),
	image_decoder_(task_runners, image_decoder_task_runner, io_manager),
	task_runners_(std::move(task_runners)),
	weak_factory_(this) {
	pointer_data_dispatcher_ = dispatcher_maker(*this);
	}

	Engine::Engine(Delegate& delegate,
	const PointerDataDispatcherMaker& dispatcher_maker,
	DartVM& vm,
	fml::RefPtr<const DartSnapshot> isolate_snapshot,
	TaskRunners task_runners,
	const PlatformData& platform_data,
	Settings settings,
	std::unique_ptr<Animator> animator,
	fml::WeakPtr<IOManager> io_manager,
	fml::RefPtr<SkiaUnrefQueue> unref_queue,
	fml::WeakPtr<SnapshotDelegate> snapshot_delegate,
	std::shared_ptr<VolatilePathTracker> volatile_path_tracker)
	: Engine(delegate,
	dispatcher_maker,
	vm.GetConcurrentWorkerTaskRunner(),
	task_runners,
	settings,
	std::move(animator),
	io_manager,
	std::make_shared<FontCollection>(),
	nullptr) {
	runtime_controller_ = std::make_unique<RuntimeController>(
	*this, // runtime delegate
	&vm, // VM
	std::move(isolate_snapshot), // isolate snapshot
	task_runners_, // task runners
	std::move(snapshot_delegate), // snapshot delegate
	GetWeakPtr(), // hint freed delegate
	std::move(io_manager), // io manager
	std::move(unref_queue), // Skia unref queue
	image_decoder_.GetWeakPtr(), // image decoder
	settings_.advisory_script_uri, // advisory script uri
	settings_.advisory_script_entrypoint, // advisory script entrypoint
	settings_.idle_notification_callback, // idle notification callback
	platform_data, // platform data
	settings_.isolate_create_callback, // isolate create callback
	settings_.isolate_shutdown_callback, // isolate shutdown callback
	settings_.persistent_isolate_data, // persistent isolate data
	std::move(volatile_path_tracker) // volatile path tracker
	);
	}

	std::unique_ptr<Engine> Engine::Spawn(
	Delegate& delegate,
	const PointerDataDispatcherMaker& dispatcher_maker,
	Settings settings,
	std::unique_ptr<Animator> animator) const {
	auto result = std::make_unique<Engine>(
	/delegate=/delegate,
	/dispatcher_maker=/dispatcher_maker,
	/image_decoder_task_runner=/
	runtime_controller_->GetDartVM()->GetConcurrentWorkerTaskRunner(),
	/task_runners=/task_runners_,
	/settings=/settings,
	/animator=/std::move(animator),
	/io_manager=/runtime_controller_->GetIOManager(),
	/font_collection=/font_collection_,
	/runtime_controller=/nullptr);
	result->runtime_controller_ = runtime_controller_->Spawn(
	*result, // runtime delegate
	settings_.advisory_script_uri, // advisory script uri
	settings_.advisory_script_entrypoint, // advisory script entrypoint
	settings_.idle_notification_callback, // idle notification callback
	settings_.isolate_create_callback, // isolate create callback
	settings_.isolate_shutdown_callback, // isolate shutdown callback
	settings_.persistent_isolate_data // persistent isolate data
	);
	return result;
	}

	Engine::~Engine() = default;

	fml::WeakPtr<Engine> Engine::GetWeakPtr() const {
	return weak_factory_.GetWeakPtr();
	}

	void Engine::SetupDefaultFontManager() {
	TRACE_EVENT0("flutter", "Engine::SetupDefaultFontManager");
	font_collection_->SetupDefaultFontManager();
	}

	std::shared_ptr<AssetManager> Engine::GetAssetManager() {
	return asset_manager_;
	}

	bool Engine::UpdateAssetManager(
	std::shared_ptr<AssetManager> new_asset_manager) {
	if (asset_manager_ == new_asset_manager) {
	return false;
	}

	asset_manager_ = new_asset_manager;

	if (!asset_manager_) {
	return false;
	}

	// Using libTXT as the text engine.
	font_collection_->RegisterFonts(asset_manager_);

	if (settings_.use_test_fonts) {
	font_collection_->RegisterTestFonts();
	}

	return true;
	}

	bool Engine::Restart(RunConfiguration configuration) {
	TRACE_EVENT0("flutter", "Engine::Restart");
	if (!configuration.IsValid()) {
	FML_LOG(ERROR) << "Engine run configuration was invalid.";
	return false;
	}
	delegate_.OnPreEngineRestart();
	runtime_controller_ = runtime_controller_->Clone();
	UpdateAssetManager(nullptr);
	return Run(std::move(configuration)) == Engine::RunStatus::Success;
	}

	Engine::RunStatus Engine::Run(RunConfiguration configuration) {
	if (!configuration.IsValid()) {
	FML_LOG(ERROR) << "Engine run configuration was invalid.";
	return RunStatus::Failure;
	}

	last_entry_point_ = configuration.GetEntrypoint();
	last_entry_point_library_ = configuration.GetEntrypointLibrary();

	UpdateAssetManager(configuration.GetAssetManager());

	if (runtime_controller_->IsRootIsolateRunning()) {
	return RunStatus::FailureAlreadyRunning;
	}

	if (!runtime_controller_->LaunchRootIsolate(
	settings_, //
	configuration.GetEntrypoint(), //
	configuration.GetEntrypointLibrary(), //
	configuration.TakeIsolateConfiguration()) //
	) {
	return RunStatus::Failure;
	}

	auto service_id = runtime_controller_->GetRootIsolateServiceID();
	if (service_id.has_value()) {
	fml::RefPtr<PlatformMessage> service_id_message =
	fml::MakeRefCounted<flutter::PlatformMessage>(
	kIsolateChannel,
	std::vector<uint8_t>(service_id.value().begin(),
	service_id.value().end()),
	nullptr);
	HandlePlatformMessage(service_id_message);
	}

	return Engine::RunStatus::Success;
	}

	void Engine::BeginFrame(fml::TimePoint frame_time) {
	TRACE_EVENT0("flutter", "Engine::BeginFrame");
	runtime_controller_->BeginFrame(frame_time);
	}

	void Engine::ReportTimings(std::vector<int64_t> timings) {
	TRACE_EVENT0("flutter", "Engine::ReportTimings");
	runtime_controller_->ReportTimings(std::move(timings));
	}

	void Engine::HintFreed(size_t size) {
	hint_freed_bytes_since_last_idle_ += size;
	}

	void Engine::NotifyIdle(int64_t deadline) {
	auto trace_event = std::to_string(deadline - Dart_TimelineGetMicros());
	TRACE_EVENT1("flutter", "Engine::NotifyIdle", "deadline_now_delta",
	trace_event.c_str());
	runtime_controller_->NotifyIdle(deadline, hint_freed_bytes_since_last_idle_);
	hint_freed_bytes_since_last_idle_ = 0;
	}

	std::optional<uint32_t> Engine::GetUIIsolateReturnCode() {
	return runtime_controller_->GetRootIsolateReturnCode();
	}

	Dart_Port Engine::GetUIIsolateMainPort() {
	return runtime_controller_->GetMainPort();
	}

	std::string Engine::GetUIIsolateName() {
	return runtime_controller_->GetIsolateName();
	}

	bool Engine::UIIsolateHasLivePorts() {
	return runtime_controller_->HasLivePorts();
	}

	tonic::DartErrorHandleType Engine::GetUIIsolateLastError() {
	return runtime_controller_->GetLastError();
	}

	void Engine::OnOutputSurfaceCreated() {
	have_surface_ = true;
	StartAnimatorIfPossible();
	ScheduleFrame();
	}

	void Engine::OnOutputSurfaceDestroyed() {
	have_surface_ = false;
	StopAnimator();
	}

	void Engine::SetViewportMetrics(const ViewportMetrics& metrics) {
	bool dimensions_changed =
	viewport_metrics_.physical_height != metrics.physical_height \|\|
	viewport_metrics_.physical_width != metrics.physical_width \|\|
	viewport_metrics_.device_pixel_ratio != metrics.device_pixel_ratio;
	viewport_metrics_ = metrics;
	runtime_controller_->SetViewportMetrics(viewport_metrics_);
	if (animator_) {
	if (dimensions_changed) {
	animator_->SetDimensionChangePending();
	}
	if (have_surface_) {
	ScheduleFrame();
	}
	}
	}

	void Engine::DispatchPlatformMessage(fml::RefPtr<PlatformMessage> message) {
	std::string channel = message->channel();
	if (channel == kLifecycleChannel) {
	if (HandleLifecyclePlatformMessage(message.get())) {
	return;
	}
	} else if (channel == kLocalizationChannel) {
	if (HandleLocalizationPlatformMessage(message.get())) {
	return;
	}
	} else if (channel == kSettingsChannel) {
	HandleSettingsPlatformMessage(message.get());
	return;
	} else if (!runtime_controller_->IsRootIsolateRunning() &&
	channel == kNavigationChannel) {
	// If there's no runtime_, we may still need to set the initial route.
	HandleNavigationPlatformMessage(std::move(message));
	return;
	}

	if (runtime_controller_->IsRootIsolateRunning() &&
	runtime_controller_->DispatchPlatformMessage(std::move(message))) {
	return;
	}

	FML_DLOG(WARNING) << "Dropping platform message on channel: " << channel;
	}

	bool Engine::HandleLifecyclePlatformMessage(PlatformMessage* message) {
	const auto& data = message->data();
	std::string state(reinterpret_cast<const char*>(data.data()), data.size());
	if (state == "AppLifecycleState.paused" \|\|
	state == "AppLifecycleState.detached") {
	activity_running_ = false;
	StopAnimator();
	} else if (state == "AppLifecycleState.resumed" \|\|
	state == "AppLifecycleState.inactive") {
	activity_running_ = true;
	StartAnimatorIfPossible();
	}

	// Always schedule a frame when the app does become active as per API
	// recommendation
	// https://developer.apple.com/documentation/uikit/uiapplicationdelegate/1622956-applicationdidbecomeactive?language=objc
	if (state == "AppLifecycleState.resumed" && have_surface_) {
	ScheduleFrame();
	}
	runtime_controller_->SetLifecycleState(state);
	// Always forward these messages to the framework by returning false.
	return false;
	}

	bool Engine::HandleNavigationPlatformMessage(
	fml::RefPtr<PlatformMessage> message) {
	const auto& data = message->data();

	rapidjson::Document document;
	document.Parse(reinterpret_cast<const char*>(data.data()), data.size());
	if (document.HasParseError() \|\| !document.IsObject()) {
	return false;
	}
	auto root = document.GetObject();
	auto method = root.FindMember("method");
	if (method->value != "setInitialRoute") {
	return false;
	}
	auto route = root.FindMember("args");
	initial_route_ = std::move(route->value.GetString());
	return true;
	}

	bool Engine::HandleLocalizationPlatformMessage(PlatformMessage* message) {
	const auto& data = message->data();

	rapidjson::Document document;
	document.Parse(reinterpret_cast<const char*>(data.data()), data.size());
	if (document.HasParseError() \|\| !document.IsObject()) {
	return false;
	}
	auto root = document.GetObject();
	auto method = root.FindMember("method");
	if (method == root.MemberEnd()) {
	return false;
	}
	const size_t strings_per_locale = 4;
	if (method->value == "setLocale") {
	// Decode and pass the list of locale data onwards to dart.
	auto args = root.FindMember("args");
	if (args == root.MemberEnd() \|\| !args->value.IsArray()) {
	return false;
	}

	if (args->value.Size() % strings_per_locale != 0) {
	return false;
	}
	std::vector<std::string> locale_data;
	for (size_t locale_index = 0; locale_index < args->value.Size();
	locale_index += strings_per_locale) {
	if (!args->value[locale_index].IsString() \|\|
	!args->value[locale_index + 1].IsString()) {
	return false;
	}
	locale_data.push_back(args->value[locale_index].GetString());
	locale_data.push_back(args->value[locale_index + 1].GetString());
	locale_data.push_back(args->value[locale_index + 2].GetString());
	locale_data.push_back(args->value[locale_index + 3].GetString());
	}

	return runtime_controller_->SetLocales(locale_data);
	}
	return false;
	}

	void Engine::HandleSettingsPlatformMessage(PlatformMessage* message) {
	const auto& data = message->data();
	std::string jsonData(reinterpret_cast<const char*>(data.data()), data.size());
	if (runtime_controller_->SetUserSettingsData(std::move(jsonData)) &&
	have_surface_) {
	ScheduleFrame();
	}
	}

	void Engine::DispatchPointerDataPacket(
	std::unique_ptr<PointerDataPacket> packet,
	uint64_t trace_flow_id) {
	TRACE_EVENT0("flutter", "Engine::DispatchPointerDataPacket");
	TRACE_FLOW_STEP("flutter", "PointerEvent", trace_flow_id);
	pointer_data_dispatcher_->DispatchPacket(std::move(packet), trace_flow_id);
	}

	void Engine::DispatchKeyDataPacket(std::unique_ptr<KeyDataPacket> packet,
	KeyDataResponse callback) {
	TRACE_EVENT0("flutter", "Engine::DispatchKeyDataPacket");
	if (runtime_controller_) {
	runtime_controller_->DispatchKeyDataPacket(*packet, std::move(callback));
	}
	}

	void Engine::DispatchSemanticsAction(int id,
	SemanticsAction action,
	std::vector<uint8_t> args) {
	runtime_controller_->DispatchSemanticsAction(id, action, std::move(args));
	}

	void Engine::SetSemanticsEnabled(bool enabled) {
	runtime_controller_->SetSemanticsEnabled(enabled);
	}

	void Engine::SetAccessibilityFeatures(int32_t flags) {
	runtime_controller_->SetAccessibilityFeatures(flags);
	}

	void Engine::StopAnimator() {
	animator_->Stop();
	}

	void Engine::StartAnimatorIfPossible() {
	if (activity_running_ && have_surface_) {
	animator_->Start();
	}
	}

	std::string Engine::DefaultRouteName() {
	if (!initial_route_.empty()) {
	return initial_route_;
	}
	return "/";
	}

	void Engine::ScheduleFrame(bool regenerate_layer_tree) {
	animator_->RequestFrame(regenerate_layer_tree);
	}

	void Engine::Render(std::unique_ptr<flutter::LayerTree> layer_tree) {
	if (!layer_tree) {
	return;
	}

	// Ensure frame dimensions are sane.
	if (layer_tree->frame_size().isEmpty() \|\|
	layer_tree->device_pixel_ratio() <= 0.0f) {
	return;
	}

	animator_->Render(std::move(layer_tree));
	}

	void Engine::UpdateSemantics(SemanticsNodeUpdates update,
	CustomAccessibilityActionUpdates actions) {
	delegate_.OnEngineUpdateSemantics(std::move(update), std::move(actions));
	}

	void Engine::HandlePlatformMessage(fml::RefPtr<PlatformMessage> message) {
	if (message->channel() == kAssetChannel) {
	HandleAssetPlatformMessage(std::move(message));
	} else {
	delegate_.OnEngineHandlePlatformMessage(std::move(message));
	}
	}

	void Engine::OnRootIsolateCreated() {
	delegate_.OnRootIsolateCreated();
	}

	void Engine::UpdateIsolateDescription(const std::string isolate_name,
	int64_t isolate_port) {
	delegate_.UpdateIsolateDescription(isolate_name, isolate_port);
	}

	std::unique_ptr<std::vector<std::string>> Engine::ComputePlatformResolvedLocale(
	const std::vector<std::string>& supported_locale_data) {
	return delegate_.ComputePlatformResolvedLocale(supported_locale_data);
	}

	void Engine::SetNeedsReportTimings(bool needs_reporting) {
	delegate_.SetNeedsReportTimings(needs_reporting);
	}

	FontCollection& Engine::GetFontCollection() {
	return *font_collection_;
	}

	void Engine::DoDispatchPacket(std::unique_ptr<PointerDataPacket> packet,
	uint64_t trace_flow_id) {
	animator_->EnqueueTraceFlowId(trace_flow_id);
	if (runtime_controller_) {
	runtime_controller_->DispatchPointerDataPacket(*packet);
	}
	}

	void Engine::ScheduleSecondaryVsyncCallback(uintptr_t id,
	const fml::closure& callback) {
	animator_->ScheduleSecondaryVsyncCallback(id, callback);
	}

	void Engine::HandleAssetPlatformMessage(fml::RefPtr<PlatformMessage> message) {
	fml::RefPtr<PlatformMessageResponse> response = message->response();
	if (!response) {
	return;
	}
	const auto& data = message->data();
	std::string asset_name(reinterpret_cast<const char*>(data.data()),
	data.size());

	if (asset_manager_) {
	std::unique_ptr<fml::Mapping> asset_mapping =
	asset_manager_->GetAsMapping(asset_name);
	if (asset_mapping) {
	response->Complete(std::move(asset_mapping));
	return;
	}
	}

	response->CompleteEmpty();
	}

	const std::string& Engine::GetLastEntrypoint() const {
	return last_entry_point_;
	}

	const std::string& Engine::GetLastEntrypointLibrary() const {
	return last_entry_point_library_;
	}

	// \|RuntimeDelegate\|
	void Engine::RequestDartDeferredLibrary(intptr_t loading_unit_id) {
	return delegate_.RequestDartDeferredLibrary(loading_unit_id);
	}

	void Engine::LoadDartDeferredLibrary(
	intptr_t loading_unit_id,
	std::unique_ptr<const fml::Mapping> snapshot_data,
	std::unique_ptr<const fml::Mapping> snapshot_instructions) {
	if (runtime_controller_->IsRootIsolateRunning()) {
	runtime_controller_->LoadDartDeferredLibrary(
	loading_unit_id, std::move(snapshot_data),
	std::move(snapshot_instructions));
	} else {
	LoadDartDeferredLibraryError(loading_unit_id, "No running root isolate.",
	true);
	}
	}

	void Engine::LoadDartDeferredLibraryError(intptr_t loading_unit_id,
	const std::string error_message,
	bool transient) {
	if (runtime_controller_->IsRootIsolateRunning()) {
	runtime_controller_->LoadDartDeferredLibraryError(loading_unit_id,
	error_message, transient);
	}
	}

	} // namespace flutter