Factor out the layout code from OpaqueBrowserFrameView for testing.

chrome/browser/ui/views/frame/opaque_browser_frame_view_layout.cc

+// Copyright (c) 2013 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/frame/opaque_browser_frame_view_layout.h"
+
+#include "ui/gfx/font.h"
+#include "ui/views/controls/button/image_button.h"
+#include "ui/views/controls/label.h"
+
+#if defined(OS_WIN)
+#include "win8/util/win8_util.h"
+#endif  // OS_WIN
+
+namespace {
+
+// Besides the frame border, there's another 9 px of empty space atop the
+// window in restored mode, to use to drag the window around.
+const int kNonClientRestoredExtraThickness = 9;
+
+// The titlebar never shrinks too short to show the caption button plus some
+// padding below it.
+const int kCaptionButtonHeightWithPadding = 19;
+
+// There is a 5 px gap between the title text and the caption buttons.
+const int kTitleLogoSpacing = 5;
+
+// The frame border is only visible in restored mode and is hardcoded to 4 px on
+// each side regardless of the system window border size.
+const int kFrameBorderThickness = 4;
+
+// The titlebar has a 2 px 3D edge along the top and bottom.
+const int kTitlebarTopAndBottomEdgeThickness = 2;
+
+// The icon is inset 2 px from the left frame border.
+const int kIconLeftSpacing = 2;
+
+// There is a 4 px gap between the icon and the title text.
+const int kIconTitleSpacing = 4;
+
+// The avatar ends 2 px above the bottom of the tabstrip (which, given the
+// way the tabstrip draws its bottom edge, will appear like a 1 px gap to the
+// user).
+const int kAvatarBottomSpacing = 2;
+
+// Space between the frame border and the left edge of the avatar.
+const int kAvatarLeftSpacing = 2;
+
+// Space between the right edge of the avatar and the tabstrip.
+const int kAvatarRightSpacing = -2;
+
+// In restored mode, the New Tab button isn't at the same height as the caption
+// buttons, but the space will look cluttered if it actually slides under them,
+// so we stop it when the gap between the two is down to 5 px.
+const int kNewTabCaptionRestoredSpacing = 5;
+
+// In maximized mode, where the New Tab button and the caption buttons are at
+// similar vertical coordinates, we need to reserve a larger, 16 px gap to avoid
+// looking too cluttered.
+const int kNewTabCaptionMaximizedSpacing = 16;
+
+// The top 3 px of the tabstrip is shadow; in maximized mode we push this off
+// the top of the screen so the tabs appear flush against the screen edge.
+const int kTabstripTopShadowThickness = 3;
+
+// How far to indent the tabstrip from the left side of the screen when there
+// is no avatar icon.
+const int kTabStripIndent = -6;
+
+}  // namespace
+
+///////////////////////////////////////////////////////////////////////////////
+// OpaqueBrowserFrameView, public:
+
+OpaqueBrowserFrameViewLayout::OpaqueBrowserFrameViewLayout(
+    OpaqueBrowserFrameViewLayoutDelegate* delegate)
+    : delegate_(delegate),
+      minimize_button_(NULL),
+      maximize_button_(NULL),
+      restore_button_(NULL),
+      close_button_(NULL),
+      window_icon_(NULL),
+      window_title_(NULL),
+      avatar_label_(NULL),
+      avatar_button_(NULL) {
+}
+
+OpaqueBrowserFrameViewLayout::~OpaqueBrowserFrameViewLayout() {}
+
+// static
+bool OpaqueBrowserFrameViewLayout::ShouldAddDefaultCaptionButtons() {
+#if defined(OS_WIN)
+  return !win8::IsSingleWindowMetroMode();
+#endif  // OS_WIN
+  return true;
+}
+
+gfx::Rect OpaqueBrowserFrameViewLayout::GetBoundsForTabStrip(
+    const gfx::Size& tabstrip_preferred_size, int available_width) const {

[sky, 2013/08/30 16:35:18]

nit: wrap each param to its own line (here and every where).

+  gfx::Rect bounds = GetBoundsForTabStripAndAvatarArea(
+      tabstrip_preferred_size, available_width);
+  int space_left_of_tabstrip = kTabStripIndent;
+  if (delegate_->ShouldShowAvatar()) {
+    if (avatar_label_ && avatar_label_->bounds().width()) {
+      // Space between the right edge of the avatar label and the tabstrip.
+      const int kAvatarLabelRightSpacing = -10;
+      space_left_of_tabstrip =
+          avatar_label_->bounds().right() + kAvatarLabelRightSpacing;
+    } else {
+      space_left_of_tabstrip =
+          kAvatarLeftSpacing + avatar_bounds_.width() +
+          kAvatarRightSpacing;
+    }
+  }
+  bounds.Inset(space_left_of_tabstrip, 0, 0, 0);
+  return bounds;
+}
+
+gfx::Rect OpaqueBrowserFrameViewLayout::GetBoundsForTabStripAndAvatarArea(
+    const gfx::Size& tabstrip_preferred_size, int available_width) const {
+  if (minimize_button_) {
+    available_width = minimize_button_->x();
+  } else if (delegate_->GetAdditionalReservedSpaceInTabStrip()) {
+    available_width -= delegate_->GetAdditionalReservedSpaceInTabStrip();
+  }
+  const int caption_spacing = delegate_->IsMaximized() ?
+      kNewTabCaptionMaximizedSpacing : kNewTabCaptionRestoredSpacing;
+  const int tabstrip_x = NonClientBorderThickness();
+  const int tabstrip_width = available_width - tabstrip_x - caption_spacing;
+  return gfx::Rect(tabstrip_x, GetTabStripInsetsTop(false),
+                   std::max(0, tabstrip_width),
+                   tabstrip_preferred_size.height());
+}
+
+gfx::Size OpaqueBrowserFrameViewLayout::GetMinimumSize(
+    int available_width) const {
+  gfx::Size min_size = delegate_->GetBrowserViewMinimumSize();
+  int border_thickness = NonClientBorderThickness();
+  min_size.Enlarge(2 * border_thickness,
+                   NonClientTopBorderHeight(false) + border_thickness);
+
+  int min_titlebar_width = (2 * FrameBorderThickness(false)) +
+      kIconLeftSpacing +
+      (delegate_->ShouldShowWindowIcon() ?
+       (delegate_->GetIconSize() + kTitleLogoSpacing) : 0);
+  if (OpaqueBrowserFrameViewLayout::ShouldAddDefaultCaptionButtons()) {

[sky, 2013/08/30 16:35:18]

nit: don't need OpaqueBrowserFrameViewLayout::

+    min_titlebar_width +=
+        minimize_button_->GetMinimumSize().width() +
+        restore_button_->GetMinimumSize().width() +
+        close_button_->GetMinimumSize().width();
+  }
+  min_size.set_width(std::max(min_size.width(), min_titlebar_width));
+
+  // Ensure that the minimum width is enough to hold a minimum width tab strip
+  // and avatar icon at their usual insets.
+  if (delegate_->IsTabStripVisible()) {
+    gfx::Size preferred_size = delegate_->GetTabstripPreferredSize();
+    const int min_tabstrip_width = preferred_size.width();
+    const int min_tabstrip_area_width =
+        available_width -
+        GetBoundsForTabStripAndAvatarArea(
+            preferred_size, available_width).width() +
+        min_tabstrip_width + delegate_->GetOTRAvatarIcon().width() +
+        kAvatarLeftSpacing + kAvatarRightSpacing;
+    min_size.set_width(std::max(min_size.width(), min_tabstrip_area_width));
+  }
+
+  return min_size;
+}
+
+gfx::Rect OpaqueBrowserFrameViewLayout::GetWindowBoundsForClientBounds(
+    const gfx::Rect& client_bounds) const {
+  int top_height = NonClientTopBorderHeight(false);
+  int border_thickness = NonClientBorderThickness();
+  return gfx::Rect(std::max(0, client_bounds.x() - border_thickness),
+                   std::max(0, client_bounds.y() - top_height),
+                   client_bounds.width() + (2 * border_thickness),
+                   client_bounds.height() + top_height + border_thickness);
+}
+
+int OpaqueBrowserFrameViewLayout::FrameBorderThickness(bool restored) const {
+  return (!restored && (delegate_->IsMaximized() ||
+                        delegate_->IsFullscreen())) ?
+      0 : kFrameBorderThickness;
+}
+
+int OpaqueBrowserFrameViewLayout::NonClientBorderThickness() const {
+  // When we fill the screen, we don't show a client edge.
+  return FrameBorderThickness(false) +
+      ((delegate_->IsMaximized() || delegate_->IsFullscreen()) ?
+       0 : views::NonClientFrameView::kClientEdgeThickness);
+}
+
+int OpaqueBrowserFrameViewLayout::NonClientTopBorderHeight(
+    bool restored) const {
+  if (delegate_->ShouldShowWindowTitle()) {
+    return std::max(FrameBorderThickness(restored) + delegate_->GetIconSize(),
+        CaptionButtonY(restored) + kCaptionButtonHeightWithPadding) +
+        TitlebarBottomThickness(restored);
+  }
+
+  return FrameBorderThickness(restored) -
+      ((delegate_->IsTabStripVisible() &&
+          !restored && !delegate_->ShouldLeaveOffsetNearTopBorder())
+              ? kTabstripTopShadowThickness : 0);
+}
+
+int OpaqueBrowserFrameViewLayout::GetTabStripInsetsTop(bool restored) const {
+  return NonClientTopBorderHeight(restored) + ((!restored &&
+      (!delegate_->ShouldLeaveOffsetNearTopBorder() ||
+      delegate_->IsFullscreen())) ?
+      0 : kNonClientRestoredExtraThickness);
+}
+
+int OpaqueBrowserFrameViewLayout::TitlebarBottomThickness(bool restored) const {
+  return kTitlebarTopAndBottomEdgeThickness +
+      ((!restored && delegate_->IsMaximized()) ? 0 :
+       views::NonClientFrameView::kClientEdgeThickness);
+}
+
+int OpaqueBrowserFrameViewLayout::CaptionButtonY(bool restored) const {
+  // Maximized buttons start at window top so that even if their images aren't
+  // drawn flush with the screen edge, they still obey Fitts' Law.
+  return (!restored && delegate_->IsMaximized()) ?
+      FrameBorderThickness(false) :
+      views::NonClientFrameView::kFrameShadowThickness;
+}
+
+gfx::Rect OpaqueBrowserFrameViewLayout::IconBounds() const {
+  int size = delegate_->GetIconSize();
+  int frame_thickness = FrameBorderThickness(false);
+  int y;
+  if (delegate_->ShouldShowWindowIcon() ||
+      delegate_->ShouldShowWindowTitle()) {
+    // Our frame border has a different "3D look" than Windows'.  Theirs has a
+    // more complex gradient on the top that they push their icon/title below;
+    // then the maximized window cuts this off and the icon/title are centered
+    // in the remaining space.  Because the apparent shape of our border is
+    // simpler, using the same positioning makes things look slightly uncentered
+    // with restored windows, so when the window is restored, instead of
+    // calculating the remaining space from below the frame border, we calculate
+    // from below the 3D edge.
+    int unavailable_px_at_top = delegate_->IsMaximized() ?
+        frame_thickness : kTitlebarTopAndBottomEdgeThickness;
+    // When the icon is shorter than the minimum space we reserve for the
+    // caption button, we vertically center it.  We want to bias rounding to put
+    // extra space above the icon, since the 3D edge (+ client edge, for
+    // restored windows) below looks (to the eye) more like additional space
+    // than does the 3D edge (or nothing at all, for maximized windows) above;
+    // hence the +1.
+    y = unavailable_px_at_top + (NonClientTopBorderHeight(false) -
+        unavailable_px_at_top - size - TitlebarBottomThickness(false) + 1) / 2;
+  } else {
+    // For "browser mode" windows, we use the native positioning, which is just
+    // below the top frame border.
+    y = frame_thickness;
+  }
+  return gfx::Rect(frame_thickness + kIconLeftSpacing, y, size, size);
+}
+
+gfx::Rect OpaqueBrowserFrameViewLayout::CalculateClientAreaBounds(
+    int width, int height) const {
+  int top_height = NonClientTopBorderHeight(false);
+  int border_thickness = NonClientBorderThickness();
+  return gfx::Rect(border_thickness, top_height,
+                   std::max(0, width - (2 * border_thickness)),
+                   std::max(0, height - top_height - border_thickness));
+}
+
+///////////////////////////////////////////////////////////////////////////////
+// OpaqueBrowserFrameView, private:
+
+void OpaqueBrowserFrameViewLayout::LayoutWindowControls(views::View* host) {
+  if (!ShouldAddDefaultCaptionButtons())
+    return;
+  bool is_maximized = delegate_->IsMaximized();
+  close_button_->SetImageAlignment(views::ImageButton::ALIGN_LEFT,
+                                   views::ImageButton::ALIGN_BOTTOM);
+  int caption_y = CaptionButtonY(false);
+  // There should always be the same number of non-shadow pixels visible to the
+  // side of the caption buttons.  In maximized mode we extend the rightmost
+  // button to the screen corner to obey Fitts' Law.
+  int right_extra_width = is_maximized ?
+      (kFrameBorderThickness -
+       views::NonClientFrameView::kFrameShadowThickness) : 0;
+  gfx::Size close_button_size = close_button_->GetPreferredSize();
+  close_button_->SetBounds(host->width() - FrameBorderThickness(false) -
+      right_extra_width - close_button_size.width(), caption_y,
+      close_button_size.width() + right_extra_width,
+      close_button_size.height());
+
+  // When the window is restored, we show a maximized button; otherwise, we show
+  // a restore button.
+  bool is_restored = !is_maximized && !delegate_->IsMinimized();
+  views::ImageButton* invisible_button = is_restored ?
+      restore_button_ : maximize_button_;
+  invisible_button->SetVisible(false);
+
+  views::ImageButton* visible_button = is_restored ?
+      maximize_button_ : restore_button_;
+  visible_button->SetVisible(true);
+  visible_button->SetImageAlignment(views::ImageButton::ALIGN_LEFT,
+                                    views::ImageButton::ALIGN_BOTTOM);
+  gfx::Size visible_button_size = visible_button->GetPreferredSize();
+  visible_button->SetBounds(close_button_->x() - visible_button_size.width(),
+                            caption_y, visible_button_size.width(),
+                            visible_button_size.height());
+
+  minimize_button_->SetVisible(true);
+  minimize_button_->SetImageAlignment(views::ImageButton::ALIGN_LEFT,
+                                      views::ImageButton::ALIGN_BOTTOM);
+  gfx::Size minimize_button_size = minimize_button_->GetPreferredSize();
+  minimize_button_->SetBounds(
+      visible_button->x() - minimize_button_size.width(), caption_y,
+      minimize_button_size.width(),
+      minimize_button_size.height());
+}
+
+void OpaqueBrowserFrameViewLayout::LayoutTitleBar() {
+  gfx::Rect icon_bounds(IconBounds());
+  if (delegate_->ShouldShowWindowIcon() && window_icon_)
+    window_icon_->SetBoundsRect(icon_bounds);
+
+  if (window_title_) {
+    bool should_show = delegate_->ShouldShowWindowTitle();
+    window_title_->SetVisible(should_show);
+
+    if (should_show) {
+      window_title_->SetText(delegate_->GetWindowTitle());
+      const int title_x = delegate_->ShouldShowWindowIcon() ?
+          icon_bounds.right() + kIconTitleSpacing : icon_bounds.x();
+      window_title_->SetBounds(title_x, icon_bounds.y(),
+          std::max(0, minimize_button_->x() - kTitleLogoSpacing - title_x),
+          icon_bounds.height());
+    }
+  }
+}
+
+void OpaqueBrowserFrameViewLayout::LayoutAvatar() {
+  // Even though the avatar is used for both incognito and profiles we always
+  // use the incognito icon to layout the avatar button. The profile icon
+  // can be customized so we can't depend on its size to perform layout.
+  gfx::ImageSkia incognito_icon = delegate_->GetOTRAvatarIcon();
+
+  int avatar_bottom = GetTabStripInsetsTop(false) +
+      delegate_->GetTabStripHeight() - kAvatarBottomSpacing;
+  int avatar_restored_y = avatar_bottom - incognito_icon.height();
+  int avatar_y = delegate_->IsMaximized() ?
+      (NonClientTopBorderHeight(false) + kTabstripTopShadowThickness) :
+      avatar_restored_y;
+  avatar_bounds_.SetRect(NonClientBorderThickness() + kAvatarLeftSpacing,
+      avatar_y, incognito_icon.width(),
+      delegate_->ShouldShowAvatar() ? (avatar_bottom - avatar_y) : 0);
+  if (avatar_button_)
+    avatar_button_->SetBoundsRect(avatar_bounds_);
+
+  if (avatar_label_) {
+    // Space between the bottom of the avatar and the bottom of the avatar
+    // label.
+    const int kAvatarLabelBottomSpacing = 3;
+    // Space between the frame border and the left edge of the avatar label.
+    const int kAvatarLabelLeftSpacing = -1;
+    gfx::Size label_size = avatar_label_->GetPreferredSize();
+    gfx::Rect label_bounds(
+        FrameBorderThickness(false) + kAvatarLabelLeftSpacing,
+        avatar_bottom - kAvatarLabelBottomSpacing - label_size.height(),
+        label_size.width(),
+        delegate_->ShouldShowAvatar() ? label_size.height() : 0);
+    avatar_label_->SetBoundsRect(label_bounds);
+  }
+}
+
+void OpaqueBrowserFrameViewLayout::SetView(int id, views::View* view) {
+  // Why do things this way instead of having an Init() method, where we're
+  // passed the views we'll handle? Because OpaqueBrowserFrameView doesn't own
+  // all the views which are part of it. The avatar stuff, for example, will be
+  // added and removed by the base class of OpaqueBrowserFrameView.
+  switch (id) {
+    case VIEW_ID_MINIMIZE_BUTTON:
+      minimize_button_ = static_cast<views::ImageButton*>(view);
+      break;
+    case VIEW_ID_MAXIMIZE_BUTTON:
+      maximize_button_ = static_cast<views::ImageButton*>(view);
+      break;
+    case VIEW_ID_RESTORE_BUTTON:
+      restore_button_ = static_cast<views::ImageButton*>(view);
+      break;
+    case VIEW_ID_CLOSE_BUTTON:
+      close_button_ = static_cast<views::ImageButton*>(view);

[sky, 2013/08/30 16:35:18]

Can you DCHECK on the view class names of the ones that need a specific type?
You'll need to add a kViewClass/GetClassName override for ImageButton (Label
already has one).

+      break;
+    case VIEW_ID_WINDOW_ICON:
+      window_icon_ = view;
+      break;
+    case VIEW_ID_WINDOW_TITLE:
+      window_title_ = static_cast<views::Label*>(view);
+      break;
+    case VIEW_ID_AVATAR_LABEL:
+      avatar_label_ = view;
+      break;
+    case VIEW_ID_AVATAR_BUTTON:
+      avatar_button_ = view;
+      break;
+    default:
+      NOTIMPLEMENTED() << "Unknown view id " << id;
+      break;
+  }
+}
+
+///////////////////////////////////////////////////////////////////////////////
+// OpaqueBrowserFrameView, views::LayoutManager:
+
+void OpaqueBrowserFrameViewLayout::Layout(views::View* host) {
+  LayoutWindowControls(host);
+  LayoutTitleBar();
+  LayoutAvatar();
+
+  client_view_bounds_ = CalculateClientAreaBounds(
+      host->width(), host->height());
+}
+
+gfx::Size OpaqueBrowserFrameViewLayout::GetPreferredSize(views::View* host) {
+  // This is never used; NonClientView::GetPreferredSize() will be called
+  // instead.
+  NOTREACHED();
+  return gfx::Size();
+}
+
+void OpaqueBrowserFrameViewLayout::ViewAdded(views::View* host,
+                                             views::View* view) {
+  SetView(view->id(), view);
+}
+
+void OpaqueBrowserFrameViewLayout::ViewRemoved(views::View* host,
+                                               views::View* view) {
+  SetView(view->id(), NULL);
+}