// 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 "chrome/browser/ui/views/chrome_views_delegate.h"

#include "base/command_line.h"
#include "base/memory/scoped_ptr.h"
#include "base/prefs/pref_service.h"
#include "base/string_util.h"
#include "base/utf_string_conversions.h"
#include "chrome/browser/browser_process.h"
#include "chrome/browser/prefs/scoped_user_pref_update.h"
#include "chrome/browser/profiles/profile_manager.h"
#include "chrome/browser/ui/views/accessibility/accessibility_event_router_views.h"
#include "chrome/common/pref_names.h"
#include "ui/base/ui_base_switches.h"
#include "ui/gfx/rect.h"
#include "ui/gfx/screen.h"
#include "ui/views/widget/native_widget.h"
#include "ui/views/widget/widget.h"

#if defined(OS_WIN)
#include <dwmapi.h>
#include "base/win/windows_version.h"
#include "chrome/browser/app_icon_win.h"
#endif

#if defined(USE_AURA)
#include "ui/aura/root_window.h"
#endif

#if defined(USE_AURA) && !defined(OS_CHROMEOS)
#include "chrome/browser/ui/host_desktop.h"
#include "ui/views/widget/desktop_aura/desktop_native_widget_aura.h"
#include "ui/views/widget/native_widget_aura.h"
#endif

#if defined(USE_ASH)
#include "ash/shell.h"
#include "chrome/browser/ui/ash/ash_init.h"
#include "chrome/browser/ui/ash/ash_util.h"
#endif

namespace {

// If the given window has a profile associated with it, use that profile's
// preference service. Otherwise, store and retrieve the data from Local State.
// This function may return NULL if the necessary pref service has not yet
// been initialized.
// TODO(mirandac): This function will also separate windows by profile in a
// multi-profile environment.
PrefService* GetPrefsForWindow(const views::Widget* window) {
  Profile* profile = reinterpret_cast<Profile*>(
      window->GetNativeWindowProperty(Profile::kProfileKey));
  if (!profile) {
    // Use local state for windows that have no explicit profile.
    return g_browser_process->local_state();
  }
  return profile->GetPrefs();
}

}  // namespace

///////////////////////////////////////////////////////////////////////////////
// ChromeViewsDelegate, views::ViewsDelegate implementation:

void ChromeViewsDelegate::SaveWindowPlacement(const views::Widget* window,
                                              const std::string& window_name,
                                              const gfx::Rect& bounds,
                                              ui::WindowShowState show_state) {
  PrefService* prefs = GetPrefsForWindow(window);
  if (!prefs)
    return;

  DCHECK(prefs->FindPreference(window_name.c_str()));
  DictionaryPrefUpdate update(prefs, window_name.c_str());
  DictionaryValue* window_preferences = update.Get();
  window_preferences->SetInteger("left", bounds.x());
  window_preferences->SetInteger("top", bounds.y());
  window_preferences->SetInteger("right", bounds.right());
  window_preferences->SetInteger("bottom", bounds.bottom());
  window_preferences->SetBoolean("maximized",
                                 show_state == ui::SHOW_STATE_MAXIMIZED);
  gfx::Rect work_area(gfx::Screen::GetScreenFor(window->GetNativeView())->
      GetDisplayMatching(bounds).work_area());
  window_preferences->SetInteger("work_area_left", work_area.x());
  window_preferences->SetInteger("work_area_top", work_area.y());
  window_preferences->SetInteger("work_area_right", work_area.right());
  window_preferences->SetInteger("work_area_bottom", work_area.bottom());
}

bool ChromeViewsDelegate::GetSavedWindowPlacement(
    const std::string& window_name,
    gfx::Rect* bounds,
    ui::WindowShowState* show_state) const {
  PrefService* prefs = g_browser_process->local_state();
  if (!prefs)
    return false;

  DCHECK(prefs->FindPreference(window_name.c_str()));
  const DictionaryValue* dictionary = prefs->GetDictionary(window_name.c_str());
  int left, top, right, bottom;
  if (!dictionary || !dictionary->GetInteger("left", &left) ||
      !dictionary->GetInteger("top", &top) ||
      !dictionary->GetInteger("right", &right) ||
      !dictionary->GetInteger("bottom", &bottom))
    return false;

  bounds->SetRect(left, top, right - left, bottom - top);

  bool maximized = false;
  if (dictionary)
    dictionary->GetBoolean("maximized", &maximized);
  *show_state = maximized ? ui::SHOW_STATE_MAXIMIZED : ui::SHOW_STATE_NORMAL;

  return true;
}

void ChromeViewsDelegate::NotifyAccessibilityEvent(
    views::View* view, ui::AccessibilityTypes::Event event_type) {
  AccessibilityEventRouterViews::GetInstance()->HandleAccessibilityEvent(
      view, event_type);
}

void ChromeViewsDelegate::NotifyMenuItemFocused(const string16& menu_name,
                                                const string16& menu_item_name,
                                                int item_index,
                                                int item_count,
                                                bool has_submenu) {
  AccessibilityEventRouterViews::GetInstance()->HandleMenuItemFocused(
      menu_name, menu_item_name, item_index, item_count, has_submenu);
}

#if defined(OS_WIN)
HICON ChromeViewsDelegate::GetDefaultWindowIcon() const {
  return GetAppIcon();
}
#endif

views::NonClientFrameView* ChromeViewsDelegate::CreateDefaultNonClientFrameView(
    views::Widget* widget) {
#if defined(USE_ASH)
  if (chrome::IsNativeViewInAsh(widget->GetNativeView()))
    return ash::Shell::GetInstance()->CreateDefaultNonClientFrameView(widget);
#endif
  return NULL;
}

bool ChromeViewsDelegate::UseTransparentWindows() const {
#if defined(USE_ASH)
  // TODO(scottmg): http://crbug.com/133312. This needs context to determine
  // if it's desktop or ash.
#if defined(OS_CHROMEOS)
  return true;
#else
  NOTIMPLEMENTED();
  return false;
#endif
#else
  return false;
#endif
}

void ChromeViewsDelegate::AddRef() {
  g_browser_process->AddRefModule();
}

void ChromeViewsDelegate::ReleaseRef() {
  g_browser_process->ReleaseModule();
}

content::WebContents* ChromeViewsDelegate::CreateWebContents(
    content::BrowserContext* browser_context,
    content::SiteInstance* site_instance) {
  return NULL;
}

void ChromeViewsDelegate::OnBeforeWidgetInit(
    views::Widget::InitParams* params,
    views::internal::NativeWidgetDelegate* delegate) {
  // If we already have a native_widget, we don't have to try to come
  // up with one.
  if (params->native_widget)
    return;

#if defined(USE_AURA) && !defined(OS_CHROMEOS)
  bool use_non_toplevel_window =
      params->parent && params->type != views::Widget::InitParams::TYPE_MENU;
#if defined(OS_WIN)
  // If we're on Vista+ with composition enabled, then we can use toplevel
  // windows for most things (they get blended via WS_EX_COMPOSITED, which
  // allows for animation effects, but also exceeding the bounds of the parent
  // window).
  if (base::win::GetVersion() >= base::win::VERSION_VISTA) {
    BOOL composition_enabled = FALSE;
    HRESULT hr = DwmIsCompositionEnabled(&composition_enabled);
    if (CommandLine::ForCurrentProcess()->HasSwitch(
            switches::kDisableDwmComposition))
      composition_enabled = FALSE;
    if (SUCCEEDED(hr) && composition_enabled) {
      if (chrome::GetActiveDesktop() != chrome::HOST_DESKTOP_TYPE_ASH &&
          params->parent &&
          params->type != views::Widget::InitParams::TYPE_CONTROL &&
          params->type != views::Widget::InitParams::TYPE_WINDOW) {
        // When we set this to false, we get a DesktopNativeWidgetAura from the
        // default case (not handled in this function).
        use_non_toplevel_window = false;
      }
    }
  }
#endif  // OS_WIN
#endif  // USE_AURA

#if defined(OS_CHROMEOS)
  // When we are doing straight chromeos builds, we still need to handle the
  // toplevel window case.
  // There may be a few remaining widgets in Chrome OS that are not top level,
  // but have neither a context nor a parent. Provide a fallback context so
  // users don't crash. Developers will hit the DCHECK and should provide a
  // context.
  DCHECK(params->parent || params->context || params->top_level)
      << "Please provide a parent or context for this widget.";
  if (!params->parent && !params->context)
    params->context = ash::Shell::GetPrimaryRootWindow();
#elif defined(USE_AURA)
  // While the majority of the time, context wasn't plumbed through due to the
  // existence of a global StackingClient, if this window is a toplevel, it's
  // possible that there is no contextual state that we can use.
  if (params->parent == NULL && params->context == NULL && params->top_level) {
    // We need to make a decision about where to place this window based on the
    // desktop type.
    switch (chrome::GetActiveDesktop()) {
      case chrome::HOST_DESKTOP_TYPE_NATIVE:
        // If we're native, we should give this window its own toplevel desktop
        // widget.
        params->native_widget = new views::DesktopNativeWidgetAura(delegate);
        break;
#if defined(USE_ASH)
      case chrome::HOST_DESKTOP_TYPE_ASH:
        // If we're in ash, give this window the context of the main monitor.
        params->context = ash::Shell::GetPrimaryRootWindow();
        break;
#endif
      default:
        NOTREACHED();
    }
  } else if (use_non_toplevel_window) {
    params->native_widget = new views::NativeWidgetAura(delegate);
  } else if (params->type != views::Widget::InitParams::TYPE_TOOLTIP) {
    // TODO(erg): Once we've threaded context to everywhere that needs it, we
    // should remove this check here.
    gfx::NativeView to_check =
        params->context ? params->context : params->parent;
    if (chrome::GetHostDesktopTypeForNativeView(to_check) ==
        chrome::HOST_DESKTOP_TYPE_NATIVE) {
      params->native_widget = new views::DesktopNativeWidgetAura(delegate);
    }
  }
#endif
}