// Copyright 2013 The Chromium Authors
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#include "chrome/browser/ash/power/idle_action_warning_observer.h"

#include <memory>

#include "ash/constants/ash_pref_names.h"
#include "base/memory/raw_ptr.h"
#include "base/metrics/histogram_macros.h"
#include "base/scoped_observation.h"
#include "base/time/time.h"
#include "chrome/browser/ash/power/idle_action_warning_dialog_view.h"
#include "chrome/browser/profiles/profile_manager.h"
#include "chromeos/ash/components/dbus/dbus_thread_manager.h"
#include "chromeos/ash/components/demo_mode/utils/demo_session_utils.h"
#include "chromeos/dbus/power/power_manager_client.h"
#include "chromeos/dbus/power/power_policy_controller.h"
#include "chromeos/dbus/power_manager/power_supply_properties.pb.h"
#include "components/prefs/pref_service.h"
#include "ui/views/widget/widget.h"
#include "ui/views/widget/widget_observer.h"

namespace ash {
namespace {

// DO NOT REORDER - used to report metrics.
enum class IdleLogoutWarningEvent {
  kShown = 0,
  kCanceled = 1,
  kMaxValue = kCanceled
};

void ReportMetricsForDemoMode(IdleLogoutWarningEvent event) {
  if (ash::demo_mode::IsDeviceInDemoMode()) {
    UMA_HISTOGRAM_ENUMERATION("DemoMode.IdleLogoutWarningEvent", event);
  }
}

chromeos::PowerPolicyController::Action GetIdleAction(bool on_battery_power) {
  PrefService* prefs = ProfileManager::GetActiveUserProfile()->GetPrefs();
  int action;
  if (on_battery_power) {
    action = prefs->GetInteger(ash::prefs::kPowerBatteryIdleAction);
  } else {
    action = prefs->GetInteger(ash::prefs::kPowerAcIdleAction);
  }
  return static_cast<chromeos::PowerPolicyController::Action>(action);
}

}  // namespace

class IdleActionWarningObserver::PowerManagerObserver
    : public chromeos::PowerManagerClient::Observer {
 public:
  PowerManagerObserver(IdleActionWarningObserver* idle_action_warning_observer,
                       chromeos::PowerManagerClient* client)
      : idle_action_warning_observer_(idle_action_warning_observer) {
    observation_.Observe(client);
  }

  void IdleActionImminent(base::TimeDelta time_until_idle_action) override {
    idle_action_warning_observer_->IdleActionImminent(time_until_idle_action);
  }
  void IdleActionDeferred() override {
    idle_action_warning_observer_->IdleActionDeferred();
  }
  void PowerChanged(
      const power_manager::PowerSupplyProperties& proto) override {
    idle_action_warning_observer_->PowerChanged(proto);
  }

 private:
  base::ScopedObservation<chromeos::PowerManagerClient, PowerManagerObserver>
      observation_{this};
  raw_ptr<IdleActionWarningObserver> idle_action_warning_observer_;
};

class IdleActionWarningObserver::WidgetObserver : public views::WidgetObserver {
 public:
  WidgetObserver(IdleActionWarningObserver* idle_action_warning_observer,
                 views::Widget* widget)
      : idle_action_warning_observer_(idle_action_warning_observer) {
    observation_.Observe(widget);
  }

  void OnWidgetDestroying(views::Widget* widget) override {
    idle_action_warning_observer_->OnWidgetDestroying(widget);
  }

 private:
  base::ScopedObservation<views::Widget, WidgetObserver> observation_{this};
  raw_ptr<IdleActionWarningObserver> idle_action_warning_observer_;
};

IdleActionWarningObserver::IdleActionWarningObserver() {
  power_manager_observer_ = std::make_unique<PowerManagerObserver>(
      this, chromeos::PowerManagerClient::Get());
}

IdleActionWarningObserver::~IdleActionWarningObserver() {
  power_manager_observer_.reset();
  widged_observer_.reset();
  if (warning_dialog_) {
    warning_dialog_->CloseDialog();
  }
}

void IdleActionWarningObserver::IdleActionImminent(
    base::TimeDelta time_until_idle_action) {
  // Only display warning if idle action is to shut down or logout.
  chromeos::PowerPolicyController::Action idle_action =
      GetIdleAction(on_battery_power_);
  if (idle_action != chromeos::PowerPolicyController::ACTION_STOP_SESSION &&
      idle_action != chromeos::PowerPolicyController::ACTION_SHUT_DOWN) {
    HideDialogIfPresent();
    return;
  }

  const base::TimeTicks idle_action_time =
      base::TimeTicks::Now() + time_until_idle_action;
  if (warning_dialog_) {
    warning_dialog_->Update(idle_action_time);
  } else {
    warning_dialog_ = new IdleActionWarningDialogView(idle_action_time);
    widged_observer_ =
        std::make_unique<WidgetObserver>(this, warning_dialog_->GetWidget());
    ReportMetricsForDemoMode(IdleLogoutWarningEvent::kShown);
  }
}

void IdleActionWarningObserver::IdleActionDeferred() {
  HideDialogIfPresent();
}

void IdleActionWarningObserver::PowerChanged(
    const power_manager::PowerSupplyProperties& proto) {
  on_battery_power_ =
      proto.battery_state() ==
      power_manager::PowerSupplyProperties_BatteryState_DISCHARGING;
}

void IdleActionWarningObserver::OnWidgetDestroying(views::Widget* widget) {
  DCHECK(warning_dialog_);
  DCHECK_EQ(widget, warning_dialog_->GetWidget());
  widged_observer_.reset();
  warning_dialog_ = nullptr;
}

void IdleActionWarningObserver::HideDialogIfPresent() {
  if (warning_dialog_) {
    warning_dialog_->CloseDialog();
    ReportMetricsForDemoMode(IdleLogoutWarningEvent::kCanceled);
  }
}

}  // namespace ash