// Copyright 2013 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 "services/service_manager/standalone/context.h"

#include <stddef.h>
#include <stdint.h>

#include <utility>
#include <vector>

#include "base/bind.h"
#include "base/command_line.h"
#include "base/files/file_path.h"
#include "base/json/json_file_value_serializer.h"
#include "base/macros.h"
#include "base/memory/ptr_util.h"
#include "base/message_loop/message_loop.h"
#include "base/path_service.h"
#include "base/process/process_info.h"
#include "base/strings/string_number_conversions.h"
#include "base/strings/string_split.h"
#include "base/strings/string_util.h"
#include "base/strings/utf_string_conversions.h"
#include "base/threading/sequenced_worker_pool.h"
#include "base/trace_event/trace_event.h"
#include "build/build_config.h"
#include "components/tracing/common/tracing_switches.h"
#include "services/catalog/catalog.h"
#include "services/service_manager/connect_params.h"
#include "services/service_manager/connect_util.h"
#include "services/service_manager/runner/common/switches.h"
#include "services/service_manager/runner/host/service_process_launcher.h"
#include "services/service_manager/service_manager.h"
#include "services/service_manager/standalone/tracer.h"
#include "services/service_manager/switches.h"
#include "services/tracing/public/cpp/provider.h"
#include "services/tracing/public/cpp/switches.h"
#include "services/tracing/public/interfaces/constants.mojom.h"
#include "services/tracing/public/interfaces/tracing.mojom.h"

#if defined(OS_MACOSX)
#include "services/service_manager/public/cpp/standalone_service/mach_broker.h"
#endif

namespace base {
class TaskRunner;
}

namespace service_manager {
namespace {

// Used to ensure we only init once.
class ServiceProcessLauncherFactoryImpl : public ServiceProcessLauncherFactory {
 public:
  ServiceProcessLauncherFactoryImpl(base::TaskRunner* launch_process_runner,
                                    ServiceProcessLauncher::Delegate* delegate)
      : launch_process_runner_(launch_process_runner),
        delegate_(delegate) {
  }

 private:
   std::unique_ptr<ServiceProcessLauncher> Create(
      const base::FilePath& service_path) override {
    return base::MakeUnique<ServiceProcessLauncher>(
        launch_process_runner_, delegate_, service_path);
  }

  base::TaskRunner* launch_process_runner_;
  ServiceProcessLauncher::Delegate* delegate_;
};

void OnInstanceQuit(const std::string& name, const Identity& identity) {
  if (name == identity.name())
    base::MessageLoop::current()->QuitWhenIdle();
}

const char kService[] = "service";

}  // namespace

Context::Context(
    ServiceProcessLauncher::Delegate* service_process_launcher_delegate,
    std::unique_ptr<base::Value> catalog_contents)
    : main_entry_time_(base::Time::Now()) {
  TRACE_EVENT0("service_manager", "Context::Context");
  const base::CommandLine& command_line =
      *base::CommandLine::ForCurrentProcess();

  bool trace_startup = command_line.HasSwitch(::switches::kTraceStartup);
  if (trace_startup) {
    tracer_.Start(
        command_line.GetSwitchValueASCII(::switches::kTraceStartup),
        command_line.GetSwitchValueASCII(::switches::kTraceStartupDuration),
        "mojo_runner.trace");
  }

  blocking_pool_ = new base::SequencedWorkerPool(
      kThreadPoolMaxThreads, "blocking_pool", base::TaskPriority::USER_VISIBLE);

  std::unique_ptr<ServiceProcessLauncherFactory>
      service_process_launcher_factory =
          base::MakeUnique<ServiceProcessLauncherFactoryImpl>(
              blocking_pool_.get(),
              service_process_launcher_delegate);
  catalog_.reset(new catalog::Catalog(std::move(catalog_contents)));
  service_manager_.reset(
      new ServiceManager(std::move(service_process_launcher_factory),
                         catalog_->TakeService()));

  bool enable_stats_collection_bindings =
      command_line.HasSwitch(tracing::kEnableStatsCollectionBindings);

  if (enable_stats_collection_bindings ||
      command_line.HasSwitch(switches::kEnableTracing)) {
    Identity source_identity = CreateServiceManagerIdentity();
    Identity tracing_identity(tracing::mojom::kServiceName, mojom::kRootUserID);
    tracing::mojom::FactoryPtr factory;
    BindInterface(service_manager(), source_identity, tracing_identity,
                  &factory);
    provider_.InitializeWithFactory(&factory);

    if (command_line.HasSwitch(tracing::kTraceStartup)) {
      tracing::mojom::CollectorPtr coordinator;
      BindInterface(service_manager(), source_identity, tracing_identity,
                    &coordinator);
      tracer_.StartCollectingFromTracingService(std::move(coordinator));
    }

    // Record the service manager startup metrics used for performance testing.
    if (enable_stats_collection_bindings) {
      tracing::mojom::StartupPerformanceDataCollectorPtr collector;
      BindInterface(service_manager(), source_identity, tracing_identity,
                    &collector);
#if defined(OS_MACOSX) || defined(OS_WIN) || defined(OS_LINUX)
      // CurrentProcessInfo::CreationTime is only defined on some platforms.
      const base::Time creation_time = base::CurrentProcessInfo::CreationTime();
      collector->SetServiceManagerProcessCreationTime(
          creation_time.ToInternalValue());
#endif
      collector->SetServiceManagerMainEntryPointTime(
          main_entry_time_.ToInternalValue());
    }
  }
}

Context::~Context() { blocking_pool_->Shutdown(); }

void Context::RunCommandLineApplication() {
  base::CommandLine* command_line = base::CommandLine::ForCurrentProcess();
  if (command_line->HasSwitch(kService))
    Run(command_line->GetSwitchValueASCII(kService));
}

void Context::Run(const std::string& name) {
  service_manager_->SetInstanceQuitCallback(base::Bind(&OnInstanceQuit, name));

  mojom::InterfaceProviderPtr remote_interfaces;
  mojom::InterfaceProviderPtr local_interfaces;

  std::unique_ptr<ConnectParams> params(new ConnectParams);
  params->set_source(CreateServiceManagerIdentity());
  params->set_target(Identity(name, mojom::kRootUserID));
  params->set_remote_interfaces(mojo::MakeRequest(&remote_interfaces));
  service_manager_->Connect(std::move(params));
}

}  // namespace service_manager