Drag and rotate windows between/within workspaces

BUG=none
TEST=new tests in workspace_manager_unittests

Review URL: http://codereview.chromium.org/8391035

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@107643 0039d316-1c4b-4281-b951-d872f2087c98

ui/aura_shell/default_container_event_filter.cc

@@ -26,6 +26,10 @@ bool DefaultContainerEventFilter::PreHandleMouseEvent(aura::Window* target,
       static_cast<DefaultContainerLayoutManager*>(owner()->layout_manager());
   DCHECK(layout_manager);
 
+  // TODO(oshima|derat): Move ToplevelWindowEventFilter to the shell,
+  // incorporate the logic below and intorduce DragObserver (or something
+  // similar) to decouple DCLM.
+
   // Notify layout manager that drag event may move/resize the target wnidow.
   if (event->type() == ui::ET_MOUSE_DRAGGED && drag_state_ == DRAG_NONE)
     layout_manager->PrepareForMoveOrResize(target, event);
@@ -36,8 +40,21 @@ bool DefaultContainerEventFilter::PreHandleMouseEvent(aura::Window* target,
     case ui::ET_MOUSE_DRAGGED:
       // Cancel move/resize if the event wasn't handled, or
       // drag_state_ didn't move to MOVE or RESIZE.
-      if (!handled || (drag_state_ == DRAG_NONE && !UpdateDragState()))
+      if (handled) {
+        switch (drag_state_) {
+          case DRAG_NONE:
+            if (!UpdateDragState())
+              layout_manager->CancelMoveOrResize(target, event);
+            break;
+          case DRAG_MOVE:
+            layout_manager->ProcessMove(target, event);
+            break;
+          case DRAG_RESIZE:
+            break;
+        }
+      } else {
         layout_manager->CancelMoveOrResize(target, event);
+      }
       break;
     case ui::ET_MOUSE_RELEASED:
       if (drag_state_ == DRAG_MOVE)

ui/aura_shell/default_container_layout_manager.cc

@@ -6,6 +6,7 @@
 
 #include "base/auto_reset.h"
 #include "ui/aura/desktop.h"
+#include "ui/aura/event.h"
 #include "ui/aura/window.h"
 #include "ui/aura/screen_aura.h"
 #include "ui/aura/window_types.h"
@@ -44,6 +45,29 @@ void DefaultContainerLayoutManager::CancelMoveOrResize(
   drag_window_ = NULL;
 }
 
+void DefaultContainerLayoutManager::ProcessMove(
+    aura::Window* drag,
+    aura::MouseEvent* event) {
+  AutoReset<bool> reset(&ignore_calculate_bounds_, true);
+
+  // TODO(oshima): Just zooming out may (and will) move/swap window without
+  // a users's intent. We probably should scroll viewport, but that may not
+  // be enough. See crbug.com/101826 for more discussion.
+  workspace_manager_->SetOverview(true);
+
+  gfx::Point point_in_owner = event->location();
+  aura::Window::ConvertPointToWindow(
+      drag,
+      owner_,
+      &point_in_owner);
+  // TODO(oshima): We should support simply moving to another
+  // workspace when the destination workspace has enough room to accomodate.
+  aura::Window* rotate_target =
+      workspace_manager_->FindRotateWindowForLocation(point_in_owner);
+  if (rotate_target)
+    workspace_manager_->RotateWindows(drag, rotate_target);
+}
+
 void DefaultContainerLayoutManager::EndMove(
     aura::Window* drag,
     aura::MouseEvent* evnet) {
@@ -52,7 +76,8 @@ void DefaultContainerLayoutManager::EndMove(
   drag_window_ = NULL;
   Workspace* workspace = workspace_manager_->GetActiveWorkspace();
   if (workspace)
-    workspace->Layout(NULL);
+    workspace->Layout(NULL, NULL);
+  workspace_manager_->SetOverview(false);
 }
 
 void DefaultContainerLayoutManager::EndResize(
@@ -62,7 +87,8 @@ void DefaultContainerLayoutManager::EndResize(
   drag_window_ = NULL;
   Workspace* workspace = workspace_manager_->GetActiveWorkspace();
   if (workspace)
-    workspace->Layout(NULL);
+    workspace->Layout(NULL, NULL);
+  workspace_manager_->SetOverview(false);
 }
 
 ////////////////////////////////////////////////////////////////////////////////

ui/aura_shell/default_container_layout_manager.h

@@ -39,6 +39,9 @@ class AURA_SHELL_EXPORT DefaultContainerLayoutManager
   // Invoked when a drag event didn't start any drag operation.
   void CancelMoveOrResize(aura::Window* drag, aura::MouseEvent* event);
 
+  // Invoked when a drag event moved the |window|.
+  void ProcessMove(aura::Window* window, aura::MouseEvent* event);
+
   // Invoked when a user finished moving window.
   void EndMove(aura::Window* drag, aura::MouseEvent* evnet);
 

ui/aura_shell/workspace/workspace.cc

@@ -5,6 +5,7 @@
 #include "ui/aura_shell/workspace/workspace.h"
 
 #include "base/logging.h"
+#include "ui/aura/desktop.h"
 #include "ui/aura/window.h"
 #include "ui/aura_shell/workspace/workspace_manager.h"
 #include "ui/gfx/compositor/layer.h"
@@ -12,6 +13,9 @@
 namespace {
 // Horizontal margin between windows.
 const int kWindowHorizontalMargin = 10;
+
+// Maximum number of windows a workspace can have.
+size_t g_max_windows_per_workspace = 2;
 }
 
 namespace aura_shell {
@@ -29,7 +33,7 @@ void Workspace::SetBounds(const gfx::Rect& bounds) {
   bool bounds_changed = bounds_ != bounds;
   bounds_ = bounds;
   if (bounds_changed)
-    Layout(NULL);
+    Layout(NULL, NULL);
 }
 
 gfx::Rect Workspace::GetWorkAreaBounds() const {
@@ -49,7 +53,7 @@ bool Workspace::AddWindowAfter(aura::Window* window, aura::Window* after) {
         std::find(windows_.begin(), windows_.end(), after);
     windows_.insert(++i, window);
   }
-  Layout(window);
+  Layout(NULL, window);
 
   return true;
 }
@@ -57,45 +61,124 @@ bool Workspace::AddWindowAfter(aura::Window* window, aura::Window* after) {
 void Workspace::RemoveWindow(aura::Window* window) {
   DCHECK(Contains(window));
   windows_.erase(std::find(windows_.begin(), windows_.end(), window));
-  Layout(NULL);
+  Layout(NULL, NULL);
 }
 
 bool Workspace::Contains(aura::Window* window) const {
   return std::find(windows_.begin(), windows_.end(), window) != windows_.end();
 }
 
+aura::Window* Workspace::FindRotateWindowForLocation(
+    const gfx::Point& position) {
+  aura::Window* active = aura::Desktop::GetInstance()->active_window();
+  if (GetTotalWindowsWidth() < bounds_.width()) {
+    // If all windows fit to the width of the workspace, it returns the
+    // window which contains |position|'s x coordinate.
+    for (aura::Window::Windows::const_iterator i = windows_.begin();
+         i != windows_.end();
+         ++i) {
+      if (active == *i)
+        continue;
+      gfx::Rect bounds = (*i)->GetTargetBounds();
+      if (bounds.x() < position.x() && position.x() < bounds.right())
+        return *i;
+    }
+  } else if (bounds_.x() < position.x() && position.x() < bounds_.right()) {
+    // If windows are overlapping, it divides the workspace into
+    // regions with the same width, and returns the Nth window that
+    // corresponds to the region that contains the |position|.
+    int width = bounds_.width() / windows_.size();
+    size_t index = (position.x() - bounds_.x()) / width;
+    DCHECK(index < windows_.size());
+    aura::Window* window = windows_[index];
+    if (window != active)
+      return window;
+  }
+  return NULL;
+}
+
+void Workspace::RotateWindows(aura::Window* source, aura::Window* target) {
+  DCHECK(Contains(source));
+  DCHECK(Contains(target));
+  aura::Window::Windows::iterator source_iter =
+      std::find(windows_.begin(), windows_.end(), source);
+  aura::Window::Windows::iterator target_iter =
+      std::find(windows_.begin(), windows_.end(), target);
+  DCHECK(source_iter != target_iter);
+  if (source_iter < target_iter)
+    std::rotate(source_iter, source_iter + 1, target_iter + 1);
+  else
+    std::rotate(target_iter, source_iter, source_iter + 1);
+  Layout(source, NULL);
+}
+
+aura::Window* Workspace::ShiftWindows(aura::Window* insert,
+                                      aura::Window* until,
+                                      aura::Window* target,
+                                      ShiftDirection direction) {
+  DCHECK(until);
+  DCHECK(!Contains(insert));
+
+  bool shift_reached_until = GetIndexOf(until) >= 0;
+  if (shift_reached_until)
+    RemoveWindow(until);
+  aura::Window* pushed = NULL;
+  if (direction == SHIFT_TO_RIGHT) {
+    aura::Window::Windows::iterator iter =
+        std::find(windows_.begin(), windows_.end(), target);
+    // Insert at |target| position, or at the begining.
+    if (iter == windows_.end())
+      iter = windows_.begin();
+    windows_.insert(iter, insert);
+    if (!shift_reached_until) {
+      pushed = windows_.back();
+      windows_.erase(--windows_.end());
+    }
+  } else {
+    aura::Window::Windows::iterator iter =
+        std::find(windows_.begin(), windows_.end(), target);
+    // Insert after |target|, or at the end.
+    if (iter != windows_.end())
+      ++iter;
+    windows_.insert(iter, insert);
+    if (!shift_reached_until) {
+      pushed = windows_.front();
+      windows_.erase(windows_.begin());
+    }
+  }
+  Layout(shift_reached_until ? until : NULL, NULL);
+  return pushed;
+}
+
 void Workspace::Activate() {
   workspace_manager_->SetActiveWorkspace(this);
 }
 
-void Workspace::Layout(aura::Window* no_animation) {
+void Workspace::Layout(aura::Window* ignore, aura::Window* no_animation) {
   gfx::Rect work_area = workspace_manager_->GetWorkAreaBounds(bounds_);
-  int total_width = 0;
-  for (aura::Window::Windows::const_iterator i = windows_.begin();
-       i != windows_.end();
-       ++i) {
-    if (total_width)
-      total_width += kWindowHorizontalMargin;
-    // TODO(oshima): use restored bounds.
-    total_width += (*i)->bounds().width();
-  }
-
+  int total_width = GetTotalWindowsWidth();
   if (total_width < work_area.width()) {
     int dx = (work_area.width() - total_width) / 2;
     for (aura::Window::Windows::iterator i = windows_.begin();
          i != windows_.end();
          ++i) {
-      MoveWindowTo(*i,
-                   gfx::Point(work_area.x() + dx, work_area.y()),
-                   no_animation != *i);
+      if (*i != ignore) {
+        MoveWindowTo(*i,
+                     gfx::Point(work_area.x() + dx, work_area.y()),
+                     no_animation != *i);
+      }
       dx += (*i)->bounds().width() + kWindowHorizontalMargin;
     }
   } else {
     DCHECK_LT(windows_.size(), 3U);
-    // TODO(oshima): Figure out general algorithm to layout more than
-    // 2 windows.
-    MoveWindowTo(windows_[0], work_area.origin(), no_animation != windows_[0]);
-    if (windows_.size() == 2) {
+    // TODO(oshima): This is messy. Figure out general algorithm to
+    // layout more than 2 windows.
+    if (windows_[0] != ignore) {
+      MoveWindowTo(windows_[0],
+                   work_area.origin(),
+                   no_animation != windows_[0]);
+    }
+    if (windows_.size() == 2 && windows_[1] != ignore) {
       MoveWindowTo(windows_[1],
                    gfx::Point(work_area.right() - windows_[1]->bounds().width(),
                               work_area.y()),
@@ -114,7 +197,7 @@ bool Workspace::CanAdd(aura::Window* window) const {
   // TODO(oshima): This should be based on available space and the
   // size of the |window|.
   NOTIMPLEMENTED();
-  return windows_.size() < 2;
+  return windows_.size() < g_max_windows_per_workspace;
 }
 
 void Workspace::MoveWindowTo(
@@ -134,4 +217,24 @@ void Workspace::MoveWindowTo(
   }
 }
 
+int Workspace::GetTotalWindowsWidth() const {
+  int total_width = 0;
+  for (aura::Window::Windows::const_iterator i = windows_.begin();
+       i != windows_.end();
+       ++i) {
+    if (total_width)
+      total_width += kWindowHorizontalMargin;
+    // TODO(oshima): use restored bounds.
+    total_width += (*i)->bounds().width();
+  }
+  return total_width;
+}
+
+// static
+size_t Workspace::SetMaxWindowsCount(size_t max) {
+  int old = g_max_windows_per_workspace;
+  g_max_windows_per_workspace = max;
+  return old;
+}
+
 }  // namespace aura_shell

ui/aura_shell/workspace/workspace.h

@@ -32,6 +32,12 @@ class AURA_SHELL_EXPORT Workspace {
   explicit Workspace(WorkspaceManager* manager);
   virtual ~Workspace();
 
+  // Specifies the direction to shift windows in |ShiftWindows()|.
+  enum ShiftDirection {
+    SHIFT_TO_RIGHT,
+    SHIFT_TO_LEFT
+  };
+
   //  Returns true if this workspace has no windows.
   bool is_empty() const { return windows_.empty(); }
 
@@ -49,23 +55,48 @@ class AURA_SHELL_EXPORT Workspace {
   // failed.
   bool AddWindowAfter(aura::Window* window, aura::Window* after);
 
-  // Removes the |window| from this workspace.
+  // Removes |window| from this workspace.
   void RemoveWindow(aura::Window* window);
 
-  // Return true if this workspace has the |window|.
+  // Return true if this workspace has |window|.
   bool Contains(aura::Window* window) const;
 
+  // Returns a window to rotate to based on |position|.
+  aura::Window* FindRotateWindowForLocation(const gfx::Point& position);
+
+  // Rotates the windows by removing |source| and inserting it to the
+  // position that |target| was in. It re-layouts windows except for |source|.
+  void RotateWindows(aura::Window* source, aura::Window* target);
+
+  // Shift the windows in the workspace by inserting |window| until it
+  // reaches |until|. If |direction| is |SHIFT_TO_RIGHT|, |insert| is
+  // inserted at the position of |target| or at the beginning if
+  // |target| is NULL. If |direction| is |SHIFT_TO_LEFT|, |insert| is
+  // inserted after the position of |target|, or at the end if
+  // |target| is NULL.  It returns the window that is overflowed by
+  // shifting, or NULL if shifting stopped at |until|.
+  aura::Window* ShiftWindows(aura::Window* insert,
+                             aura::Window* until,
+                             aura::Window* target,
+                             ShiftDirection direction);
+
   // Activates this workspace.
   void Activate();
 
-  // Layout windows. Moving animation is applied to all windows except
-  // for the window specified by |no_animation|.
-  void Layout(aura::Window* no_animation);
+  // Layout windows. The workspace doesn't set bounds on |ignore| if it's
+  // given. It still uses |ignore| window's bounds to calculate
+  // bounds for other windows. Moving animation is applied to all
+  // windows except for the window specified by |no_animation| and |ignore|.
+  void Layout(aura::Window* ignore, aura::Window* no_animation);
 
  private:
   FRIEND_TEST_ALL_PREFIXES(WorkspaceTest, WorkspaceBasic);
+  FRIEND_TEST_ALL_PREFIXES(WorkspaceTest, RotateWindows);
+  FRIEND_TEST_ALL_PREFIXES(WorkspaceTest, ShiftWindowsSingle);
+  FRIEND_TEST_ALL_PREFIXES(WorkspaceTest, ShiftWindowsMultiple);
+  FRIEND_TEST_ALL_PREFIXES(WorkspaceManagerTest, RotateWindows);
 
-  // Returns the index in layout order of the |window| in this workspace.
+  // Returns the index in layout order of |window| in this workspace.
   int GetIndexOf(aura::Window* window) const;
 
   // Returns true if the given |window| can be added to this workspace.
@@ -77,6 +108,14 @@ class AURA_SHELL_EXPORT Workspace {
                     const gfx::Point& origin,
                     bool animate);
 
+  // Returns the sum of all window's width.
+  int GetTotalWindowsWidth() const;
+
+  // Test only: Changes how may windows workspace can have.
+  // Returns the current value so that it can be reverted back to
+  // original value.
+  static size_t SetMaxWindowsCount(size_t max);
+
   WorkspaceManager* workspace_manager_;
 
   gfx::Rect bounds_;

ui/aura_shell/workspace/workspace_manager.cc

@@ -60,11 +60,18 @@ Workspace* WorkspaceManager::GetActiveWorkspace() const {
 }
 
 Workspace* WorkspaceManager::FindBy(aura::Window* window) const {
+  int index = GetWorkspaceIndexContaining(window);
+  return index < 0 ? NULL : workspaces_[index];
+}
+
+aura::Window* WorkspaceManager::FindRotateWindowForLocation(
+    const gfx::Point& point) {
   for (Workspaces::const_iterator i = workspaces_.begin();
        i != workspaces_.end();
        ++i) {
-    if ((*i)->Contains(window))
-      return *i;
+    aura::Window* window = (*i)->FindRotateWindowForLocation(point);
+    if (window)
+      return window;
   }
   return NULL;
 }
@@ -128,6 +135,36 @@ void WorkspaceManager::SetOverview(bool overview) {
   viewport_->layer()->SetTransform(transform);
 }
 
+void WorkspaceManager::RotateWindows(aura::Window* source,
+                                     aura::Window* target) {
+  DCHECK(source);
+  DCHECK(target);
+  int source_ws_index = GetWorkspaceIndexContaining(source);
+  int target_ws_index = GetWorkspaceIndexContaining(target);
+  DCHECK(source_ws_index >= 0);
+  DCHECK(target_ws_index >= 0);
+  if (source_ws_index == target_ws_index) {
+    workspaces_[source_ws_index]->RotateWindows(source, target);
+  } else {
+    aura::Window* insert = source;
+    if (source_ws_index < target_ws_index) {
+      for (int i = target_ws_index; i >= source_ws_index; --i) {
+        insert = workspaces_[i]->ShiftWindows(
+            insert, source, target, Workspace::SHIFT_TO_LEFT);
+        // |target| can only be in the 1st workspace.
+        target = NULL;
+      }
+    } else {
+      for (int i = target_ws_index; i <= source_ws_index; ++i) {
+        insert = workspaces_[i]->ShiftWindows(
+            insert, source, target, Workspace::SHIFT_TO_RIGHT);
+        // |target| can only be in the 1st workspace.
+        target = NULL;
+      }
+    }
+  }
+}
+
 ////////////////////////////////////////////////////////////////////////////////
 // WorkspaceManager, Overridden from aura::DesktopObserver:
 
@@ -186,6 +223,17 @@ gfx::Rect WorkspaceManager::GetWorkAreaBounds(
   return bounds;
 }
 
+// Returns the index of the workspace that contains the |window|.
+int WorkspaceManager::GetWorkspaceIndexContaining(aura::Window* window) const {
+  for (Workspaces::const_iterator i = workspaces_.begin();
+       i != workspaces_.end();
+       ++i) {
+    if ((*i)->Contains(window))
+      return i - workspaces_.begin();
+  }
+  return -1;
+}
+
 void WorkspaceManager::UpdateViewport() {
   int num_workspaces = std::max(1, static_cast<int>(workspaces_.size()));
   int total_width = workspace_size_.width() * num_workspaces +

ui/aura_shell/workspace/workspace_manager.h

@@ -44,6 +44,9 @@ class AURA_SHELL_EXPORT WorkspaceManager : public aura::DesktopObserver {
   // Returns the workspace that contanis the |window|.
   Workspace* FindBy(aura::Window* window) const;
 
+  // Returns the window for rotate operation based on the |location|.
+  aura::Window* FindRotateWindowForLocation(const gfx::Point& location);
+
   // Sets the bounds of all workspaces.
   void LayoutWorkspaces();
 
@@ -54,6 +57,9 @@ class AURA_SHELL_EXPORT WorkspaceManager : public aura::DesktopObserver {
   void SetOverview(bool overview);
   bool is_overview() const { return is_overview_; }
 
+  // Rotate windows by moving |source| window to the position of |target|.
+  void RotateWindows(aura::Window* source, aura::Window* target);
+
   // Overridden from aura::DesktopObserver:
   virtual void OnDesktopResized(const gfx::Size& new_size) OVERRIDE;
   virtual void OnActiveWindowChanged(aura::Window* active) OVERRIDE;
@@ -62,6 +68,7 @@ class AURA_SHELL_EXPORT WorkspaceManager : public aura::DesktopObserver {
   friend class Workspace;
   FRIEND_TEST_ALL_PREFIXES(WorkspaceManagerTest, Overview);
   FRIEND_TEST_ALL_PREFIXES(WorkspaceManagerTest, LayoutWorkspaces);
+  FRIEND_TEST_ALL_PREFIXES(WorkspaceManagerTest, FindRotateWindow);
 
   void AddWorkspace(Workspace* workspace);
   void RemoveWorkspace(Workspace* workspace);
@@ -72,6 +79,9 @@ class AURA_SHELL_EXPORT WorkspaceManager : public aura::DesktopObserver {
   // Returns the bounds of the work are given |workspace_bounds|.
   gfx::Rect GetWorkAreaBounds(const gfx::Rect& workspace_bounds);
 
+  // Returns the index of the workspace that contains the |window|.
+  int GetWorkspaceIndexContaining(aura::Window* window) const;
+
   // Update viewport size and move to the active workspace.
   void UpdateViewport();
 

ui/aura_shell/workspace/workspace_manager_unittest.cc

@@ -15,6 +15,19 @@ namespace {
 
 class WorkspaceManagerTestBase : public aura::test::AuraTestBase {
  public:
+  WorkspaceManagerTestBase() {}
+  virtual ~WorkspaceManagerTestBase() {}
+
+  virtual void SetUp() OVERRIDE {
+    aura::test::AuraTestBase::SetUp();
+    manager_.reset(new aura_shell::WorkspaceManager(viewport()));
+  }
+
+  virtual void TearDown() OVERRIDE {
+    manager_.reset();
+    aura::test::AuraTestBase::TearDown();
+  }
+
   aura::Window* CreateTestWindow() {
     aura::Window* window = new aura::Window(NULL);
     window->Init(ui::Layer::LAYER_HAS_NO_TEXTURE);
@@ -24,6 +37,10 @@ class WorkspaceManagerTestBase : public aura::test::AuraTestBase {
   aura::Window* viewport() {
     return GetTestDesktopDelegate()->default_container();
   }
+  scoped_ptr<aura_shell::WorkspaceManager> manager_;
+
+ private:
+  DISALLOW_COPY_AND_ASSIGN(WorkspaceManagerTestBase);
 };
 
 }  // namespace
@@ -38,46 +55,47 @@ class WorkspaceManagerTest : public WorkspaceManagerTestBase {
 };
 
 TEST_F(WorkspaceManagerTest, WorkspaceManagerCreateAddFind) {
-  WorkspaceManager manager(viewport());
   scoped_ptr<Window> w1(CreateTestWindow());
   scoped_ptr<Window> w2(CreateTestWindow());
 
-  Workspace* ws1 = manager.CreateWorkspace();
+  Workspace* ws1 = manager_->CreateWorkspace();
   ws1->AddWindowAfter(w1.get(), NULL);
   // w2 is not a part of any workspace yet.
-  EXPECT_EQ(NULL, manager.FindBy(w2.get()));
+  EXPECT_EQ(NULL, manager_->FindBy(w2.get()));
 
   // w2 is in ws2 workspace.
-  Workspace* ws2 = manager.CreateWorkspace();
+  Workspace* ws2 = manager_->CreateWorkspace();
   ws2->AddWindowAfter(w2.get(), NULL);
-  EXPECT_EQ(ws2, manager.FindBy(w2.get()));
+  EXPECT_EQ(ws2, manager_->FindBy(w2.get()));
 
   // Make sure |FindBy(w1.get())| still returns
   // correct workspace.
-  EXPECT_EQ(ws1, manager.FindBy(w1.get()));
+  EXPECT_EQ(ws1, manager_->FindBy(w1.get()));
 
   // once workspace is gone, w2 shouldn't match
   // any workspace.
   delete ws2;
-  EXPECT_EQ(NULL, manager.FindBy(w2.get()));
+  EXPECT_EQ(NULL, manager_->FindBy(w2.get()));
+
+  // Reset now before windows are destroyed.
+  manager_.reset();
 }
 
 TEST_F(WorkspaceManagerTest, LayoutWorkspaces) {
-  WorkspaceManager manager(viewport());
-  manager.workspace_size_ = gfx::Size(100, 100);
-  manager.LayoutWorkspaces();
+  manager_->workspace_size_ = gfx::Size(100, 100);
+  manager_->LayoutWorkspaces();
   EXPECT_EQ("0,0 100x100", viewport()->bounds().ToString());
 
-  Workspace* ws1 = manager.CreateWorkspace();
-  manager.LayoutWorkspaces();
+  Workspace* ws1 = manager_->CreateWorkspace();
+  manager_->LayoutWorkspaces();
 
   // ws1 is laied out in left most position.
   EXPECT_EQ(100, viewport()->bounds().width());
   EXPECT_EQ("0,0 100x100", ws1->bounds().ToString());
 
   // ws2 is laied out next to ws1, with 50 margin.
-  Workspace* ws2 = manager.CreateWorkspace();
-  manager.LayoutWorkspaces();
+  Workspace* ws2 = manager_->CreateWorkspace();
+  manager_->LayoutWorkspaces();
 
   EXPECT_EQ(250, viewport()->bounds().width());
   EXPECT_EQ("0,0 100x100", ws1->bounds().ToString());
@@ -87,87 +105,188 @@ TEST_F(WorkspaceManagerTest, LayoutWorkspaces) {
 TEST_F(WorkspaceManagerTest, WorkspaceManagerDragArea) {
   aura::Desktop::GetInstance()->screen()->set_work_area_insets(
       gfx::Insets(10, 10, 10, 10));
-
-  WorkspaceManager manager(viewport());
   viewport()->SetBounds(gfx::Rect(0, 0, 200, 200));
-  EXPECT_EQ("10,10 180x180", manager.GetDragAreaBounds().ToString());
+  EXPECT_EQ("10,10 180x180", manager_->GetDragAreaBounds().ToString());
 }
 
 TEST_F(WorkspaceManagerTest, Overview) {
-  WorkspaceManager manager(viewport());
-  manager.workspace_size_ = gfx::Size(500, 300);
+  manager_->workspace_size_ = gfx::Size(500, 300);
 
   // Creating two workspaces, ws1 which contains window w1,
   // and ws2 which contains window w2.
-  Workspace* ws1 = manager.CreateWorkspace();
+  Workspace* ws1 = manager_->CreateWorkspace();
   scoped_ptr<Window> w1(CreateTestWindow());
   viewport()->AddChild(w1.get());
   EXPECT_TRUE(ws1->AddWindowAfter(w1.get(), NULL));
 
-  Workspace* ws2 = manager.CreateWorkspace();
+  Workspace* ws2 = manager_->CreateWorkspace();
   scoped_ptr<Window> w2(CreateTestWindow());
   viewport()->AddChild(w2.get());
   EXPECT_TRUE(ws2->AddWindowAfter(w2.get(), NULL));
 
   // Activating a window switches the active workspace.
   w2->Activate();
-  EXPECT_EQ(ws2, manager.GetActiveWorkspace());
+  EXPECT_EQ(ws2, manager_->GetActiveWorkspace());
 
   // The size of viewport() is now ws1(500) + ws2(500) + margin(50).
   EXPECT_EQ("0,0 1050x300", viewport()->bounds().ToString());
-  EXPECT_FALSE(manager.is_overview());
-  manager.SetOverview(true);
-  EXPECT_TRUE(manager.is_overview());
+  EXPECT_FALSE(manager_->is_overview());
+  manager_->SetOverview(true);
+  EXPECT_TRUE(manager_->is_overview());
 
   // Switching overview mode doesn't change the active workspace.
-  EXPECT_EQ(ws2, manager.GetActiveWorkspace());
+  EXPECT_EQ(ws2, manager_->GetActiveWorkspace());
 
   // Activaing window w1 switches the active window and
   // the mode back to normal mode.
   w1->Activate();
-  EXPECT_EQ(ws1, manager.GetActiveWorkspace());
-  EXPECT_FALSE(manager.is_overview());
+  EXPECT_EQ(ws1, manager_->GetActiveWorkspace());
+  EXPECT_FALSE(manager_->is_overview());
 
   // Deleting w1 without DesktopDelegate resets the active workspace
   ws1->RemoveWindow(w1.get());
   delete ws1;
   w1.reset();
-  EXPECT_EQ(NULL, manager.GetActiveWorkspace());
-
+  EXPECT_EQ(NULL, manager_->GetActiveWorkspace());
   EXPECT_EQ("0,0 500x300", viewport()->bounds().ToString());
   ws2->RemoveWindow(w2.get());
   delete ws2;
   // The size of viewport() for no workspace case must be
   // same as one viewport() case.
   EXPECT_EQ("0,0 500x300", viewport()->bounds().ToString());
+
+  // Reset now before windows are destroyed.
+  manager_.reset();
 }
 
 TEST_F(WorkspaceManagerTest, WorkspaceManagerActivate) {
-  WorkspaceManager manager(viewport());
-  Workspace* ws1 = manager.CreateWorkspace();
-  Workspace* ws2 = manager.CreateWorkspace();
-  EXPECT_EQ(NULL, manager.GetActiveWorkspace());
+  Workspace* ws1 = manager_->CreateWorkspace();
+  Workspace* ws2 = manager_->CreateWorkspace();
+  EXPECT_EQ(NULL, manager_->GetActiveWorkspace());
 
   // Activate ws1.
   ws1->Activate();
-  EXPECT_EQ(ws1, manager.GetActiveWorkspace());
+  EXPECT_EQ(ws1, manager_->GetActiveWorkspace());
 
   // Activate ws2.
   ws2->Activate();
-  EXPECT_EQ(ws2, manager.GetActiveWorkspace());
+  EXPECT_EQ(ws2, manager_->GetActiveWorkspace());
 
   // Deleting active workspace sets active workspace to NULL.
   delete ws2;
-  EXPECT_EQ(NULL, manager.GetActiveWorkspace());
+  EXPECT_EQ(NULL, manager_->GetActiveWorkspace());
+  manager_.reset();
+}
+
+TEST_F(WorkspaceManagerTest, FindRotateWindow) {
+  manager_->workspace_size_ = gfx::Size(500, 300);
+
+  Workspace* ws1 = manager_->CreateWorkspace();
+  scoped_ptr<Window> w11(CreateTestWindow());
+  w11->SetBounds(gfx::Rect(0, 0, 100, 100));
+  ws1->AddWindowAfter(w11.get(), NULL);
+
+  scoped_ptr<Window> w12(CreateTestWindow());
+  w12->SetBounds(gfx::Rect(0, 0, 100, 100));
+  ws1->AddWindowAfter(w12.get(), NULL);
+  manager_->LayoutWorkspaces();
+
+  // Workspaces are 0-empt-145-w11-245-margin-265-365-500.
+  EXPECT_EQ(NULL, manager_->FindRotateWindowForLocation(gfx::Point(0, 0)));
+  EXPECT_EQ(NULL, manager_->FindRotateWindowForLocation(gfx::Point(100, 0)));
+  EXPECT_EQ(w11.get(),
+            manager_->FindRotateWindowForLocation(gfx::Point(150, 0)));
+  EXPECT_EQ(w12.get(),
+            manager_->FindRotateWindowForLocation(gfx::Point(300, 0)));
+  EXPECT_EQ(NULL, manager_->FindRotateWindowForLocation(gfx::Point(400, 0)));
+
+  w11->SetBounds(gfx::Rect(0, 0, 400, 100));
+  w12->SetBounds(gfx::Rect(0, 0, 200, 100));
+  manager_->LayoutWorkspaces();
+  EXPECT_EQ(w11.get(),
+            manager_->FindRotateWindowForLocation(gfx::Point(10, 0)));
+  EXPECT_EQ(w11.get(),
+            manager_->FindRotateWindowForLocation(gfx::Point(240, 0)));
+  EXPECT_EQ(w12.get(),
+            manager_->FindRotateWindowForLocation(gfx::Point(260, 0)));
+  EXPECT_EQ(w12.get(),
+            manager_->FindRotateWindowForLocation(gfx::Point(490, 0)));
+
+  Workspace* ws2 = manager_->CreateWorkspace();
+  scoped_ptr<Window> w21(CreateTestWindow());
+  w21->SetBounds(gfx::Rect(0, 0, 100, 100));
+  ws2->AddWindowAfter(w21.get(), NULL);
+  manager_->LayoutWorkspaces();
+
+  // 2nd workspace starts from 500+50 and the window is centered 750-850.
+  EXPECT_EQ(NULL, manager_->FindRotateWindowForLocation(gfx::Point(600, 0)));
+  EXPECT_EQ(NULL, manager_->FindRotateWindowForLocation(gfx::Point(740, 0)));
+  EXPECT_EQ(w21.get(),
+            manager_->FindRotateWindowForLocation(gfx::Point(760, 0)));
+  EXPECT_EQ(w21.get(),
+            manager_->FindRotateWindowForLocation(gfx::Point(840, 0)));
+  EXPECT_EQ(NULL, manager_->FindRotateWindowForLocation(gfx::Point(860, 0)));
+
+  // Reset now before windows are destroyed.
+  manager_.reset();
+}
+
+TEST_F(WorkspaceManagerTest, RotateWindows) {
+  Workspace* ws1 = manager_->CreateWorkspace();
+  Workspace* ws2 = manager_->CreateWorkspace();
+
+  scoped_ptr<Window> w11(CreateTestWindow());
+  ws1->AddWindowAfter(w11.get(), NULL);
+
+  scoped_ptr<Window> w21(CreateTestWindow());
+  scoped_ptr<Window> w22(CreateTestWindow());
+  ws2->AddWindowAfter(w21.get(), NULL);
+  ws2->AddWindowAfter(w22.get(), NULL);
+
+  EXPECT_EQ(0, ws1->GetIndexOf(w11.get()));
+  EXPECT_EQ(0, ws2->GetIndexOf(w21.get()));
+  EXPECT_EQ(1, ws2->GetIndexOf(w22.get()));
+
+  // Rotate right most to left most.
+  manager_->RotateWindows(w22.get(), w11.get());
+
+  EXPECT_EQ(0, ws1->GetIndexOf(w22.get()));
+  EXPECT_EQ(0, ws2->GetIndexOf(w11.get()));
+  EXPECT_EQ(1, ws2->GetIndexOf(w21.get()));
+
+  // Rotate left most to right most.
+  manager_->RotateWindows(w22.get(), w21.get());
+  EXPECT_EQ(0, ws1->GetIndexOf(w11.get()));
+  EXPECT_EQ(0, ws2->GetIndexOf(w21.get()));
+  EXPECT_EQ(1, ws2->GetIndexOf(w22.get()));
+
+  // Rotate left most to 1st element in 2nd workspace.
+  manager_->RotateWindows(w11.get(), w21.get());
+  EXPECT_EQ(0, ws1->GetIndexOf(w21.get()));
+  EXPECT_EQ(0, ws2->GetIndexOf(w11.get()));
+  EXPECT_EQ(1, ws2->GetIndexOf(w22.get()));
+
+  // Rotate middle to right most.
+  manager_->RotateWindows(w11.get(), w22.get());
+  EXPECT_EQ(0, ws1->GetIndexOf(w21.get()));
+  EXPECT_EQ(0, ws2->GetIndexOf(w22.get()));
+  EXPECT_EQ(1, ws2->GetIndexOf(w11.get()));
+
+  // Rotate middle to left most.
+  manager_->RotateWindows(w22.get(), w21.get());
+  EXPECT_EQ(0, ws1->GetIndexOf(w22.get()));
+  EXPECT_EQ(0, ws2->GetIndexOf(w21.get()));
+  EXPECT_EQ(1, ws2->GetIndexOf(w11.get()));
+
+  // Reset now before windows are destroyed.
+  manager_.reset();
 }
 
 class WorkspaceTest : public WorkspaceManagerTestBase {
 };
 
 TEST_F(WorkspaceTest, WorkspaceBasic) {
-  WorkspaceManager manager(viewport());
-
-  Workspace* ws = manager.CreateWorkspace();
+  Workspace* ws = manager_->CreateWorkspace();
   // Sanity check
   EXPECT_TRUE(ws->is_empty());
 
@@ -207,6 +326,167 @@ TEST_F(WorkspaceTest, WorkspaceBasic) {
   EXPECT_TRUE(ws->AddWindowAfter(w1.get(), w2.get()));
   EXPECT_EQ(0, ws->GetIndexOf(w2.get()));
   EXPECT_EQ(1, ws->GetIndexOf(w1.get()));
+
+  // Reset now before windows are destroyed.
+  manager_.reset();
+}
+
+TEST_F(WorkspaceTest, RotateWindows) {
+  size_t orig_max = Workspace::SetMaxWindowsCount(3);
+  Workspace* ws = manager_->CreateWorkspace();
+  scoped_ptr<Window> w1(CreateTestWindow());
+  scoped_ptr<Window> w2(CreateTestWindow());
+  scoped_ptr<Window> w3(CreateTestWindow());
+  ws->AddWindowAfter(w1.get(), NULL);
+  ws->AddWindowAfter(w2.get(), NULL);
+  ws->AddWindowAfter(w3.get(), NULL);
+
+  EXPECT_EQ(0, ws->GetIndexOf(w1.get()));
+  EXPECT_EQ(1, ws->GetIndexOf(w2.get()));
+  EXPECT_EQ(2, ws->GetIndexOf(w3.get()));
+
+  // Rotate to left.
+  ws->RotateWindows(w1.get(), w3.get());
+  EXPECT_EQ(0, ws->GetIndexOf(w2.get()));
+  EXPECT_EQ(1, ws->GetIndexOf(w3.get()));
+  EXPECT_EQ(2, ws->GetIndexOf(w1.get()));
+
+  // Rotate to right.
+  ws->RotateWindows(w1.get(), w2.get());
+  EXPECT_EQ(0, ws->GetIndexOf(w1.get()));
+  EXPECT_EQ(1, ws->GetIndexOf(w2.get()));
+  EXPECT_EQ(2, ws->GetIndexOf(w3.get()));
+
+  // Rotating to the middle from left.
+  ws->RotateWindows(w1.get(), w2.get());
+  EXPECT_EQ(0, ws->GetIndexOf(w2.get()));
+  EXPECT_EQ(1, ws->GetIndexOf(w1.get()));
+  EXPECT_EQ(2, ws->GetIndexOf(w3.get()));
+
+  // Rotating to the middle from right.
+  ws->RotateWindows(w3.get(), w1.get());
+  EXPECT_EQ(0, ws->GetIndexOf(w2.get()));
+  EXPECT_EQ(1, ws->GetIndexOf(w3.get()));
+  EXPECT_EQ(2, ws->GetIndexOf(w1.get()));
+
+  // Reset now before windows are destroyed.
+  manager_.reset();
+  Workspace::SetMaxWindowsCount(orig_max);
+}
+
+TEST_F(WorkspaceTest, ShiftWindowsSingle) {
+  Workspace* ws = manager_->CreateWorkspace();
+  // Single window in a workspace case.
+  scoped_ptr<Window> w1(CreateTestWindow());
+  ws->AddWindowAfter(w1.get(), NULL);
+
+  scoped_ptr<Window> w2(CreateTestWindow());
+
+  // Sanity check.
+  EXPECT_EQ(0, ws->GetIndexOf(w1.get()));
+  EXPECT_EQ(-1, ws->GetIndexOf(w2.get()));
+
+  // Insert |w2| at the beginning and shift.
+  aura::Window* overflow =
+      ws->ShiftWindows(
+          w2.get(), w2.get(), NULL, Workspace::SHIFT_TO_RIGHT);
+  EXPECT_EQ(w1.get(), overflow);
+  EXPECT_EQ(-1, ws->GetIndexOf(w1.get()));
+  EXPECT_EQ(0, ws->GetIndexOf(w2.get()));
+
+  // Insert |w1| at the end and shift.
+  overflow = ws->ShiftWindows(
+      w1.get(), w1.get(), NULL, Workspace::SHIFT_TO_LEFT);
+  EXPECT_EQ(w2.get(), overflow);
+  EXPECT_EQ(-1, ws->GetIndexOf(w2.get()));
+  EXPECT_EQ(0, ws->GetIndexOf(w1.get()));
+
+  // Insert |w2| at the begining and shift up to the w1.
+  overflow = ws->ShiftWindows(
+      w2.get(), w1.get(), NULL, Workspace::SHIFT_TO_RIGHT);
+  EXPECT_EQ(NULL, overflow);
+  EXPECT_EQ(-1, ws->GetIndexOf(w1.get()));
+  EXPECT_EQ(0, ws->GetIndexOf(w2.get()));
+
+  // Insert |w1| at the end and shift up to the w2.
+  overflow = ws->ShiftWindows(
+      w1.get(), w2.get(), NULL, Workspace::SHIFT_TO_LEFT);
+  EXPECT_EQ(NULL, overflow);
+  EXPECT_EQ(-1, ws->GetIndexOf(w2.get()));
+  EXPECT_EQ(0, ws->GetIndexOf(w1.get()));
+
+  // Reset now before windows are destroyed.
+  manager_.reset();
+}
+
+TEST_F(WorkspaceTest, ShiftWindowsMultiple) {
+  Workspace* ws = manager_->CreateWorkspace();
+  // Single window in a workspace case.
+  scoped_ptr<Window> w1(CreateTestWindow());
+  scoped_ptr<Window> w2(CreateTestWindow());
+  ws->AddWindowAfter(w1.get(), NULL);
+  ws->AddWindowAfter(w2.get(), NULL);
+
+  scoped_ptr<Window> w3(CreateTestWindow());
+
+  // Sanity check.
+  EXPECT_EQ(0, ws->GetIndexOf(w1.get()));
+  EXPECT_EQ(1, ws->GetIndexOf(w2.get()));
+  EXPECT_EQ(-1, ws->GetIndexOf(w3.get()));
+
+  // Insert |w3| at the beginning and shift.
+  aura::Window* overflow =
+      ws->ShiftWindows(w3.get(), w3.get(), NULL,
+                       Workspace::SHIFT_TO_RIGHT);
+  EXPECT_EQ(w2.get(), overflow);
+  EXPECT_EQ(-1, ws->GetIndexOf(w2.get()));
+  EXPECT_EQ(0, ws->GetIndexOf(w3.get()));
+  EXPECT_EQ(1, ws->GetIndexOf(w1.get()));
+
+  // Insert |w3| at the end and shift.
+  overflow = ws->ShiftWindows(w2.get(), w2.get(), NULL,
+                              Workspace::SHIFT_TO_LEFT);
+  EXPECT_EQ(w3.get(), overflow);
+  EXPECT_EQ(-1, ws->GetIndexOf(w3.get()));
+  EXPECT_EQ(0, ws->GetIndexOf(w1.get()));
+  EXPECT_EQ(1, ws->GetIndexOf(w2.get()));
+
+  // Insert |w3| at the begining and shift up to the w1.
+  overflow = ws->ShiftWindows(w3.get(), w1.get(), NULL,
+                              Workspace::SHIFT_TO_RIGHT);
+  EXPECT_EQ(NULL, overflow);
+  EXPECT_EQ(-1, ws->GetIndexOf(w1.get()));
+  EXPECT_EQ(0, ws->GetIndexOf(w3.get()));
+  EXPECT_EQ(1, ws->GetIndexOf(w2.get()));
+
+  // Insert |w1| at the end and shift up to the w2.
+  overflow = ws->ShiftWindows(w1.get(), w2.get(), NULL,
+                              Workspace::SHIFT_TO_LEFT);
+  EXPECT_EQ(NULL, overflow);
+  EXPECT_EQ(-1, ws->GetIndexOf(w2.get()));
+  EXPECT_EQ(0, ws->GetIndexOf(w3.get()));
+  EXPECT_EQ(1, ws->GetIndexOf(w1.get()));
+
+  scoped_ptr<Window> unused(CreateTestWindow());
+
+  // Insert |w2| at the |w3| and shift to right.
+  overflow = ws->ShiftWindows(w2.get(), unused.get(), w3.get(),
+                              Workspace::SHIFT_TO_RIGHT);
+  EXPECT_EQ(w1.get(), overflow);
+  EXPECT_EQ(-1, ws->GetIndexOf(w1.get()));
+  EXPECT_EQ(0, ws->GetIndexOf(w2.get()));
+  EXPECT_EQ(1, ws->GetIndexOf(w3.get()));
+
+  // Insert |w1| at the |w2| and shift to left.
+  overflow = ws->ShiftWindows(w1.get(), unused.get(), w2.get(),
+                              Workspace::SHIFT_TO_LEFT);
+  EXPECT_EQ(w2.get(), overflow);
+  EXPECT_EQ(-1, ws->GetIndexOf(w2.get()));
+  EXPECT_EQ(0, ws->GetIndexOf(w1.get()));
+  EXPECT_EQ(1, ws->GetIndexOf(w3.get()));
+
+  // Reset now before windows are destroyed.
+  manager_.reset();
 }
 
 }  // namespace aura_shell