// Copyright (c) 2012 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 "content/public/browser/browser_main_runner.h"

#include "base/base_switches.h"
#include "base/command_line.h"
#include "base/debug/debugger.h"
#include "base/debug/leak_annotations.h"
#include "base/lazy_instance.h"
#include "base/logging.h"
#include "base/macros.h"
#include "base/message_loop/message_loop.h"
#include "base/metrics/histogram_macros.h"
#include "base/run_loop.h"
#include "base/time/time.h"
#include "base/trace_event/heap_profiler_allocation_context_tracker.h"
#include "base/trace_event/trace_event.h"
#include "build/build_config.h"
#include "components/tracing/common/trace_config_file.h"
#include "components/tracing/common/tracing_switches.h"
#include "content/browser/browser_main_loop.h"
#include "content/browser/browser_shutdown_profile_dumper.h"
#include "content/browser/notification_service_impl.h"
#include "content/common/content_switches_internal.h"
#include "content/public/browser/tracing_controller.h"
#include "content/public/common/content_switches.h"
#include "content/public/common/main_function_params.h"
#include "third_party/skia/include/core/SkGraphics.h"
#include "ui/base/ime/input_method_initializer.h"

#if defined(OS_ANDROID)
#include "content/browser/android/tracing_controller_android.h"
#endif

#if defined(OS_WIN)
#include "base/win/windows_version.h"
#include "ui/base/win/scoped_ole_initializer.h"
#include "ui/gfx/win/direct_write.h"
#endif

namespace content {

namespace {

base::LazyInstance<base::AtomicFlag>::Leaky g_exited_main_message_loop;

}  // namespace

class BrowserMainRunnerImpl : public BrowserMainRunner {
 public:
  BrowserMainRunnerImpl()
      : initialization_started_(false), is_shutdown_(false) {}

  ~BrowserMainRunnerImpl() override {
    if (initialization_started_ && !is_shutdown_)
      Shutdown();
  }

  int Initialize(const MainFunctionParams& parameters) override {
    SCOPED_UMA_HISTOGRAM_LONG_TIMER(
        "Startup.BrowserMainRunnerImplInitializeLongTime");
    TRACE_EVENT0("startup", "BrowserMainRunnerImpl::Initialize");

    // On Android we normally initialize the browser in a series of UI thread
    // tasks. While this is happening a second request can come from the OS or
    // another application to start the browser. If this happens then we must
    // not run these parts of initialization twice.
    if (!initialization_started_) {
      initialization_started_ = true;

      const base::TimeTicks start_time_step1 = base::TimeTicks::Now();

      SkGraphics::Init();

      if (parameters.command_line.HasSwitch(switches::kWaitForDebugger))
        base::debug::WaitForDebugger(60, true);

      if (parameters.command_line.HasSwitch(switches::kBrowserStartupDialog))
        WaitForDebugger("Browser");

      notification_service_.reset(new NotificationServiceImpl);

#if defined(OS_WIN)
      // Ole must be initialized before starting message pump, so that TSF
      // (Text Services Framework) module can interact with the message pump
      // on Windows 8 Metro mode.
      ole_initializer_.reset(new ui::ScopedOleInitializer);
      // Enable DirectWrite font rendering if needed.
      gfx::win::MaybeInitializeDirectWrite();
#endif  // OS_WIN

      main_loop_.reset(new BrowserMainLoop(parameters));

      main_loop_->Init();

      main_loop_->EarlyInitialization();

      // Must happen before we try to use a message loop or display any UI.
      if (!main_loop_->InitializeToolkit())
        return 1;

      main_loop_->PreMainMessageLoopStart();
      main_loop_->MainMessageLoopStart();
      main_loop_->PostMainMessageLoopStart();

// WARNING: If we get a WM_ENDSESSION, objects created on the stack here
// are NOT deleted. If you need something to run during WM_ENDSESSION add it
// to browser_shutdown::Shutdown or BrowserProcess::EndSession.

      ui::InitializeInputMethod();
      UMA_HISTOGRAM_TIMES("Startup.BrowserMainRunnerImplInitializeStep1Time",
                          base::TimeTicks::Now() - start_time_step1);
    }
    const base::TimeTicks start_time_step2 = base::TimeTicks::Now();
    main_loop_->CreateStartupTasks();
    int result_code = main_loop_->GetResultCode();
    if (result_code > 0)
      return result_code;

    UMA_HISTOGRAM_TIMES("Startup.BrowserMainRunnerImplInitializeStep2Time",
                        base::TimeTicks::Now() - start_time_step2);

    // Return -1 to indicate no early termination.
    return -1;
  }

#if defined(OS_ANDROID)
  void SynchronouslyFlushStartupTasks() override {
    main_loop_->SynchronouslyFlushStartupTasks();
  }
#endif

  int Run() override {
    DCHECK(initialization_started_);
    DCHECK(!is_shutdown_);
    main_loop_->RunMainMessageLoopParts();
    return main_loop_->GetResultCode();
  }

  void Shutdown() override {
    DCHECK(initialization_started_);
    DCHECK(!is_shutdown_);

#ifdef LEAK_SANITIZER
    // Invoke leak detection now, to avoid dealing with shutdown-only leaks.
    // Normally this will have already happened in
    // BroserProcessImpl::ReleaseModule(), so this call has no effect. This is
    // only for processes which do not instantiate a BrowserProcess.
    // If leaks are found, the process will exit here.
    __lsan_do_leak_check();
#endif

    main_loop_->PreShutdown();

    // If startup tracing has not been finished yet, replace it's dumper
    // with special version, which would save trace file on exit (i.e.
    // startup tracing becomes a version of shutdown tracing).
    // There are two cases:
    // 1. Startup duration is not reached.
    // 2. Or startup duration is not specified for --trace-config-file flag.
    std::unique_ptr<BrowserShutdownProfileDumper> startup_profiler;
    if (main_loop_->is_tracing_startup_for_duration()) {
      main_loop_->StopStartupTracingTimer();
      if (main_loop_->startup_trace_file() !=
          base::FilePath().AppendASCII("none")) {
        startup_profiler.reset(
            new BrowserShutdownProfileDumper(main_loop_->startup_trace_file()));
      }
    } else if (tracing::TraceConfigFile::GetInstance()->IsEnabled() &&
               TracingController::GetInstance()->IsTracing()) {
      base::FilePath result_file;
#if defined(OS_ANDROID)
      TracingControllerAndroid::GenerateTracingFilePath(&result_file);
#else
      result_file = tracing::TraceConfigFile::GetInstance()->GetResultFile();
#endif
      startup_profiler.reset(new BrowserShutdownProfileDumper(result_file));
    }

    // The shutdown tracing got enabled in AttemptUserExit earlier, but someone
    // needs to write the result to disc. For that a dumper needs to get created
    // which will dump the traces to disc when it gets destroyed.
    const base::CommandLine& command_line =
        *base::CommandLine::ForCurrentProcess();
    std::unique_ptr<BrowserShutdownProfileDumper> shutdown_profiler;
    if (command_line.HasSwitch(switches::kTraceShutdown)) {
      shutdown_profiler.reset(new BrowserShutdownProfileDumper(
          BrowserShutdownProfileDumper::GetShutdownProfileFileName()));
    }

    {
      // The trace event has to stay between profiler creation and destruction.
      TRACE_EVENT0("shutdown", "BrowserMainRunner");
      g_exited_main_message_loop.Get().Set();

      main_loop_->ShutdownThreadsAndCleanUp();

      ui::ShutdownInputMethod();
  #if defined(OS_WIN)
      ole_initializer_.reset(NULL);
  #endif
  #if defined(OS_ANDROID)
      // Forcefully terminates the RunLoop inside MessagePumpForUI, ensuring
      // proper shutdown for content_browsertests. Shutdown() is not used by
      // the actual browser.
      if (base::RunLoop::IsRunningOnCurrentThread())
        base::RunLoop::QuitCurrentDeprecated();
  #endif
      main_loop_.reset(nullptr);

      notification_service_.reset(nullptr);

      is_shutdown_ = true;
    }
  }

 protected:
  // True if we have started to initialize the runner.
  bool initialization_started_;

  // True if the runner has been shut down.
  bool is_shutdown_;

  std::unique_ptr<NotificationServiceImpl> notification_service_;
  std::unique_ptr<BrowserMainLoop> main_loop_;
#if defined(OS_WIN)
  std::unique_ptr<ui::ScopedOleInitializer> ole_initializer_;
#endif

 private:
  DISALLOW_COPY_AND_ASSIGN(BrowserMainRunnerImpl);
};

// static
BrowserMainRunner* BrowserMainRunner::Create() {
  return new BrowserMainRunnerImpl();
}

// static
bool BrowserMainRunner::ExitedMainMessageLoop() {
  return g_exited_main_message_loop.IsCreated() &&
         g_exited_main_message_loop.Get().IsSet();
}

}  // namespace content