// Copyright 2020 The Chromium Authors
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#ifndef CHROME_BROWSER_PROFILES_KEEP_ALIVE_SCOPED_PROFILE_KEEP_ALIVE_H_
#define CHROME_BROWSER_PROFILES_KEEP_ALIVE_SCOPED_PROFILE_KEEP_ALIVE_H_

#include <memory>

#include "base/memory/weak_ptr.h"

class Profile;
enum class ProfileKeepAliveOrigin;

// Prevents a Profile from getting destroyed before the browser shuts down, e.g.
// because there's a UI window or job in progress that needs the Profile. Use
// these objects with a unique_ptr for easy management.
//
// This does not affect BrowserProcess lifetime, so the browser can still shut
// down if the user asks for it (which will cause Profile deletion). If you
// don't want the browser to shut down, you should use a ScopedKeepAlive as
// well.
//
// This is a no-op when the DestroyProfileOnBrowserClose flag is disabled.
//
// This is only meant for non-OTR Profile. Trying to acquire a keepalive on an
// off-the-record Profile triggers a DCHECK.
class ScopedProfileKeepAlive {
 public:
  // Same as the constructor, but returns nullptr if the keepalive count could
  // not be incremented. This can happen if the profile is scheduled for
  // deletion (in <1s).
  //
  // You can check the return value of TryAcquire() and abort long-running jobs,
  // etc. that rely on the profile.
  //
  // TODO(crbug.com/368360956): Migrate existing call-sites to this, and remove
  // the public constructor.
  [[nodiscard]] static std::unique_ptr<ScopedProfileKeepAlive> TryAcquire(
      Profile* profile,
      ProfileKeepAliveOrigin origin);

  // Do not use this is new code. prefer TryAcquire() above.
  ScopedProfileKeepAlive(Profile* profile, ProfileKeepAliveOrigin origin);
  ~ScopedProfileKeepAlive();

  ScopedProfileKeepAlive(const ScopedProfileKeepAlive&) = delete;
  ScopedProfileKeepAlive& operator=(const ScopedProfileKeepAlive&) = delete;

  Profile* profile() { return profile_.get(); }
  ProfileKeepAliveOrigin origin() const { return origin_; }

 private:
  // For TryAcquire().
  ScopedProfileKeepAlive();

  // Called after the ScopedProfileKeepAlive has been deleted, so this is a
  // static method where we pass parameters manually.
  static void RemoveKeepAliveOnUIThread(base::WeakPtr<Profile> profile,
                                        ProfileKeepAliveOrigin origin);

  // Helper for TryAcquire() and the constructor.
  static bool AddKeepAlive(Profile* profile, ProfileKeepAliveOrigin origin);

  base::WeakPtr<Profile> profile_;
  ProfileKeepAliveOrigin origin_;
};

#endif  // CHROME_BROWSER_PROFILES_KEEP_ALIVE_SCOPED_PROFILE_KEEP_ALIVE_H_