Drag and rotate windows

ui/aura_shell/workspace/workspace.cc

 // Copyright (c) 2011 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 "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"
 
 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 {
 
 Workspace::Workspace(WorkspaceManager* manager)
     : workspace_manager_(manager) {
   workspace_manager_->AddWorkspace(this);
 }
 
 Workspace::~Workspace() {
   workspace_manager_->RemoveWorkspace(this);
 }
 
 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 {
   return workspace_manager_->GetWorkAreaBounds(bounds_);
 }
 
 bool Workspace::AddWindowAfter(aura::Window* window, aura::Window* after) {
   if (!CanAdd(window))
     return false;
   DCHECK(!Contains(window));
 
   if (!after) {  // insert at the end.
     windows_.push_back(window);
   } else {
     DCHECK(Contains(after));
     aura::Window::Windows::iterator i =
         std::find(windows_.begin(), windows_.end(), after);
     windows_.insert(++i, window);
   }
-  Layout(window);
+  Layout(NULL, window);
 
   return true;
 }
 
 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()),
                    no_animation != windows_[1]);
     }
   }
 }
 
 int Workspace::GetIndexOf(aura::Window* window) const {
   aura::Window::Windows::const_iterator i =
       std::find(windows_.begin(), windows_.end(), window);
   return i == windows_.end() ? -1 : i - windows_.begin();
 }
 
 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(
     aura::Window* window,
     const gfx::Point& origin,
     bool animate) {
   if (window->show_state() == ui::SHOW_STATE_FULLSCREEN)
     window->Fullscreen();
   else if (window->show_state() == ui::SHOW_STATE_MAXIMIZED)
     window->Maximize();
   else {
     gfx::Rect bounds = window->GetTargetBounds();
     bounds.set_origin(origin);
     if (animate)
       window->layer()->SetAnimation(aura::Window::CreateDefaultAnimation());
     window->SetBounds(bounds);
   }
 }
 
+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