// Copyright 2014 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 "extensions/shell/browser/shell_desktop_controller_aura.h"

#include <algorithm>
#include <string>
#include <vector>

#include "base/command_line.h"
#include "base/macros.h"
#include "build/build_config.h"
#include "extensions/browser/app_window/app_window.h"
#include "extensions/browser/app_window/native_app_window.h"
#include "extensions/shell/browser/shell_app_delegate.h"
#include "extensions/shell/browser/shell_app_window_client.h"
#include "extensions/shell/browser/shell_screen.h"
#include "extensions/shell/common/switches.h"
#include "ui/aura/client/cursor_client.h"
#include "ui/aura/client/default_capture_client.h"
#include "ui/aura/layout_manager.h"
#include "ui/aura/window.h"
#include "ui/aura/window_event_dispatcher.h"
#include "ui/aura/window_tree_host.h"
#include "ui/base/cursor/cursor.h"
#include "ui/base/cursor/image_cursors.h"
#include "ui/base/ime/input_method_initializer.h"
#include "ui/base/user_activity/user_activity_detector.h"
#include "ui/gfx/geometry/size.h"
#include "ui/gfx/native_widget_types.h"
#include "ui/gfx/screen.h"
#include "ui/wm/core/base_focus_rules.h"
#include "ui/wm/core/compound_event_filter.h"
#include "ui/wm/core/cursor_manager.h"
#include "ui/wm/core/focus_controller.h"
#include "ui/wm/core/native_cursor_manager.h"
#include "ui/wm/core/native_cursor_manager_delegate.h"

#if defined(OS_CHROMEOS)
#include "chromeos/dbus/dbus_thread_manager.h"
#include "ui/chromeos/user_activity_power_manager_notifier.h"
#include "ui/display/types/display_mode.h"
#include "ui/display/types/display_snapshot.h"
#endif

namespace extensions {
namespace {

// A simple layout manager that makes each new window fill its parent.
class FillLayout : public aura::LayoutManager {
 public:
  FillLayout() {}
  ~FillLayout() override {}

 private:
  // aura::LayoutManager:
  void OnWindowResized() override {}

  void OnWindowAddedToLayout(aura::Window* child) override {
    if (!child->parent())
      return;

    // Create a rect at 0,0 with the size of the parent.
    gfx::Size parent_size = child->parent()->bounds().size();
    child->SetBounds(gfx::Rect(parent_size));
  }

  void OnWillRemoveWindowFromLayout(aura::Window* child) override {}

  void OnWindowRemovedFromLayout(aura::Window* child) override {}

  void OnChildWindowVisibilityChanged(aura::Window* child,
                                      bool visible) override {}

  void SetChildBounds(aura::Window* child,
                      const gfx::Rect& requested_bounds) override {
    SetChildBoundsDirect(child, requested_bounds);
  }

  DISALLOW_COPY_AND_ASSIGN(FillLayout);
};

// A class that bridges the gap between CursorManager and Aura. It borrows
// heavily from AshNativeCursorManager.
class ShellNativeCursorManager : public wm::NativeCursorManager {
 public:
  explicit ShellNativeCursorManager(aura::WindowTreeHost* host)
      : host_(host), image_cursors_(new ui::ImageCursors) {}
  ~ShellNativeCursorManager() override {}

  // wm::NativeCursorManager overrides.
  void SetDisplay(const gfx::Display& display,
                  wm::NativeCursorManagerDelegate* delegate) override {
    if (image_cursors_->SetDisplay(display, display.device_scale_factor()))
      SetCursor(delegate->GetCursor(), delegate);
  }

  void SetCursor(gfx::NativeCursor cursor,
                 wm::NativeCursorManagerDelegate* delegate) override {
    image_cursors_->SetPlatformCursor(&cursor);
    cursor.set_device_scale_factor(image_cursors_->GetScale());
    delegate->CommitCursor(cursor);

    if (delegate->IsCursorVisible())
      ApplyCursor(cursor);
  }

  void SetVisibility(bool visible,
                     wm::NativeCursorManagerDelegate* delegate) override {
    delegate->CommitVisibility(visible);

    if (visible) {
      SetCursor(delegate->GetCursor(), delegate);
    } else {
      gfx::NativeCursor invisible_cursor(ui::kCursorNone);
      image_cursors_->SetPlatformCursor(&invisible_cursor);
      ApplyCursor(invisible_cursor);
    }
  }

  void SetCursorSet(ui::CursorSetType cursor_set,
                    wm::NativeCursorManagerDelegate* delegate) override {
    image_cursors_->SetCursorSet(cursor_set);
    delegate->CommitCursorSet(cursor_set);
    if (delegate->IsCursorVisible())
      SetCursor(delegate->GetCursor(), delegate);
  }

  void SetMouseEventsEnabled(
      bool enabled,
      wm::NativeCursorManagerDelegate* delegate) override {
    delegate->CommitMouseEventsEnabled(enabled);
    SetVisibility(delegate->IsCursorVisible(), delegate);
  }

 private:
  // Sets |cursor| as the active cursor within Aura.
  void ApplyCursor(gfx::NativeCursor cursor) { host_->SetCursor(cursor); }

  aura::WindowTreeHost* host_;  // Not owned.

  scoped_ptr<ui::ImageCursors> image_cursors_;

  DISALLOW_COPY_AND_ASSIGN(ShellNativeCursorManager);
};

class AppsFocusRules : public wm::BaseFocusRules {
 public:
  AppsFocusRules() {}
  ~AppsFocusRules() override {}

  bool SupportsChildActivation(aura::Window* window) const override {
    return true;
  }

 private:
  DISALLOW_COPY_AND_ASSIGN(AppsFocusRules);
};

}  // namespace

ShellDesktopControllerAura::ShellDesktopControllerAura()
    : app_window_client_(new ShellAppWindowClient) {
  extensions::AppWindowClient::Set(app_window_client_.get());

#if defined(OS_CHROMEOS)
  chromeos::DBusThreadManager::Get()->GetPowerManagerClient()->AddObserver(
      this);
  display_configurator_.reset(new ui::DisplayConfigurator);
  display_configurator_->Init(false);
  display_configurator_->ForceInitialConfigure(0);
  display_configurator_->AddObserver(this);
#endif
  CreateRootWindow();
}

ShellDesktopControllerAura::~ShellDesktopControllerAura() {
  CloseAppWindows();
  DestroyRootWindow();
#if defined(OS_CHROMEOS)
  chromeos::DBusThreadManager::Get()->GetPowerManagerClient()->RemoveObserver(
      this);
#endif
  extensions::AppWindowClient::Set(NULL);
}

gfx::Size ShellDesktopControllerAura::GetWindowSize() {
  return host_->window()->bounds().size();
}

AppWindow* ShellDesktopControllerAura::CreateAppWindow(
    content::BrowserContext* context,
    const Extension* extension) {
  app_windows_.push_back(
      new AppWindow(context, new ShellAppDelegate, extension));
  return app_windows_.back();
}

void ShellDesktopControllerAura::AddAppWindow(gfx::NativeWindow window) {
  aura::Window* root_window = host_->window();
  root_window->AddChild(window);
}

void ShellDesktopControllerAura::RemoveAppWindow(AppWindow* window) {
  auto iter = std::find(app_windows_.begin(), app_windows_.end(), window);
  DCHECK(iter != app_windows_.end());
  app_windows_.erase(iter);
}

void ShellDesktopControllerAura::CloseAppWindows() {
  // Create a copy of the window vector, because closing the windows will
  // trigger RemoveAppWindow, which will invalidate the iterator.
  // This vector should be small enough that this should not be an issue.
  std::vector<AppWindow*> app_windows(app_windows_);
  for (AppWindow* app_window : app_windows)
    app_window->GetBaseWindow()->Close();  // Close() deletes |app_window|.
  app_windows_.clear();
}

aura::Window* ShellDesktopControllerAura::GetDefaultParent(
    aura::Window* context,
    aura::Window* window,
    const gfx::Rect& bounds) {
  return host_->window();
}

#if defined(OS_CHROMEOS)
void ShellDesktopControllerAura::PowerButtonEventReceived(
    bool down,
    const base::TimeTicks& timestamp) {
  if (down) {
    chromeos::DBusThreadManager::Get()
        ->GetPowerManagerClient()
        ->RequestShutdown();
  }
}

void ShellDesktopControllerAura::OnDisplayModeChanged(
    const ui::DisplayConfigurator::DisplayStateList& displays) {
  gfx::Size size = GetPrimaryDisplaySize();
  if (!size.IsEmpty())
    host_->UpdateRootWindowSize(size);
}
#endif

void ShellDesktopControllerAura::OnHostCloseRequested(
    const aura::WindowTreeHost* host) {
  DCHECK_EQ(host_.get(), host);
  CloseAppWindows();
  base::MessageLoop::current()->PostTask(
      FROM_HERE, base::MessageLoop::QuitWhenIdleClosure());
}

void ShellDesktopControllerAura::InitWindowManager() {
  wm::FocusController* focus_controller =
      new wm::FocusController(new AppsFocusRules());
  aura::client::SetFocusClient(host_->window(), focus_controller);
  host_->window()->AddPreTargetHandler(focus_controller);
  aura::client::SetActivationClient(host_->window(), focus_controller);
  focus_client_.reset(focus_controller);

  capture_client_.reset(
      new aura::client::DefaultCaptureClient(host_->window()));

  // Ensure new windows fill the display.
  host_->window()->SetLayoutManager(new FillLayout);

  cursor_manager_.reset(
      new wm::CursorManager(scoped_ptr<wm::NativeCursorManager>(
          new ShellNativeCursorManager(host_.get()))));
  cursor_manager_->SetDisplay(gfx::Screen::GetScreen()->GetPrimaryDisplay());
  cursor_manager_->SetCursor(ui::kCursorPointer);
  aura::client::SetCursorClient(host_->window(), cursor_manager_.get());

  user_activity_detector_.reset(new ui::UserActivityDetector);
#if defined(OS_CHROMEOS)
  user_activity_notifier_.reset(
      new ui::UserActivityPowerManagerNotifier(user_activity_detector_.get()));
#endif
}

void ShellDesktopControllerAura::CreateRootWindow() {
  // Set up basic pieces of ui::wm.
  gfx::Size size;
  base::CommandLine* command_line = base::CommandLine::ForCurrentProcess();
  if (command_line->HasSwitch(switches::kAppShellHostWindowSize)) {
    const std::string size_str =
        command_line->GetSwitchValueASCII(switches::kAppShellHostWindowSize);
    int width, height;
    CHECK_EQ(2, sscanf(size_str.c_str(), "%dx%d", &width, &height));
    size = gfx::Size(width, height);
  } else {
    size = GetPrimaryDisplaySize();
  }
  if (size.IsEmpty())
    size = gfx::Size(1920, 1080);

  screen_.reset(new ShellScreen(size));
  gfx::Screen::SetScreenInstance(screen_.get());
  // TODO(mukai): Set up input method.

  host_.reset(screen_->CreateHostForPrimaryDisplay());
  aura::client::SetWindowTreeClient(host_->window(), this);
  root_window_event_filter_.reset(new wm::CompoundEventFilter);
  host_->window()->AddPreTargetHandler(root_window_event_filter_.get());
  InitWindowManager();

  host_->AddObserver(this);

  // Ensure the X window gets mapped.
  host_->Show();
}

void ShellDesktopControllerAura::DestroyRootWindow() {
  host_->RemoveObserver(this);
  wm::FocusController* focus_controller =
      static_cast<wm::FocusController*>(focus_client_.get());
  if (focus_controller) {
    host_->window()->RemovePreTargetHandler(focus_controller);
    aura::client::SetActivationClient(host_->window(), NULL);
  }
  root_window_event_filter_.reset();
  capture_client_.reset();
  focus_client_.reset();
  cursor_manager_.reset();
#if defined(OS_CHROMEOS)
  user_activity_notifier_.reset();
#endif
  user_activity_detector_.reset();
  host_.reset();
  screen_.reset();
}

gfx::Size ShellDesktopControllerAura::GetPrimaryDisplaySize() {
#if defined(OS_CHROMEOS)
  const ui::DisplayConfigurator::DisplayStateList& displays =
      display_configurator_->cached_displays();
  if (displays.empty())
    return gfx::Size();
  const ui::DisplayMode* mode = displays[0]->current_mode();
  return mode ? mode->size() : gfx::Size();
#else
  return gfx::Size();
#endif
}

}  // namespace extensions