Move WindowImpl to gfx so I can use it there for canvas unit tests.

BUG=none
TEST=none

Review URL: http://codereview.chromium.org/2813042

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@51554 0039d316-1c4b-4281-b951-d872f2087c98

3 files changed, 345 insertions, 0 deletions

diff --git a/gfx/gfx.gyp b/gfx/gfx.gyp
index 592901c..668ac00 100644
--- a/gfx/gfx.gyp
+++ b/gfx/gfx.gyp
@@ -113,7 +113,13 @@
             'icon_util.h',
             'native_theme_win.cc',
             'native_theme_win.h',
+            'window_impl.cc',
+            'window_impl.h'
           ],
+          'include_dirs': [
+            '..',
+            '<(DEPTH)/third_party/wtl/include',
+          ],          
         }],
         ['OS=="linux" or OS=="freebsd" or OS=="openbsd"', {
           'dependencies': [
diff --git a/gfx/window_impl.cc b/gfx/window_impl.cc
new file mode 100644
index 0000000..86eecce
--- /dev/null
+++ b/gfx/window_impl.cc
@@ -0,0 +1,226 @@
+// Copyright (c) 2009 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 "gfx/window_impl.h"
+
+#include <list>
+
+#include "base/singleton.h"
+#include "base/string_util.h"
+#include "base/win_util.h"
+
+namespace gfx {
+
+static const DWORD kWindowDefaultChildStyle =
+    WS_CHILD | WS_VISIBLE | WS_CLIPCHILDREN | WS_CLIPSIBLINGS;
+static const DWORD kWindowDefaultStyle = WS_OVERLAPPEDWINDOW;
+static const DWORD kWindowDefaultExStyle = 0;
+
+///////////////////////////////////////////////////////////////////////////////
+// WindowImpl class tracking.
+
+// Several external scripts rely explicitly on this base class name for
+// acquiring the window handle and will break if this is modified!
+// static
+const wchar_t* const WindowImpl::kBaseClassName = L"Chrome_WidgetWin_";
+
+// WindowImpl class information used for registering unique windows.
+struct ClassInfo {
+  UINT style;
+  HBRUSH background;
+
+  explicit ClassInfo(int style)
+      : style(style),
+        background(NULL) {}
+
+  // Compares two ClassInfos. Returns true if all members match.
+  bool Equals(const ClassInfo& other) const {
+    return (other.style == style && other.background == background);
+  }
+};
+
+class ClassRegistrar {
+ public:
+  ~ClassRegistrar() {
+    for (RegisteredClasses::iterator i = registered_classes_.begin();
+         i != registered_classes_.end(); ++i) {
+      UnregisterClass(i->name.c_str(), NULL);
+    }
+  }
+
+  // Puts the name for the class matching |class_info| in |class_name|, creating
+  // a new name if the class is not yet known.
+  // Returns true if this class was already known, false otherwise.
+  bool RetrieveClassName(const ClassInfo& class_info, std::wstring* name) {
+    for (RegisteredClasses::const_iterator i = registered_classes_.begin();
+         i != registered_classes_.end(); ++i) {
+      if (class_info.Equals(i->info)) {
+        name->assign(i->name);
+        return true;
+      }
+    }
+
+    name->assign(std::wstring(WindowImpl::kBaseClassName) +
+        IntToWString(registered_count_++));
+    return false;
+  }
+
+  void RegisterClass(const ClassInfo& class_info,
+                     const std::wstring& name,
+                     ATOM atom) {
+    registered_classes_.push_back(RegisteredClass(class_info, name, atom));
+  }
+
+ private:
+  // Represents a registered window class.
+  struct RegisteredClass {
+    RegisteredClass(const ClassInfo& info,
+                    const std::wstring& name,
+                    ATOM atom)
+        : info(info),
+          name(name),
+          atom(atom) {
+    }
+
+    // Info used to create the class.
+    ClassInfo info;
+
+    // The name given to the window.
+    std::wstring name;
+
+    // The ATOM returned from creating the window.
+    ATOM atom;
+  };
+
+  ClassRegistrar() : registered_count_(0) { }
+  friend struct DefaultSingletonTraits<ClassRegistrar>;
+
+  typedef std::list<RegisteredClass> RegisteredClasses;
+  RegisteredClasses registered_classes_;
+
+  // Counter of how many classes have been registered so far.
+  int registered_count_;
+
+  DISALLOW_COPY_AND_ASSIGN(ClassRegistrar);
+};
+
+///////////////////////////////////////////////////////////////////////////////
+// WindowImpl, public
+
+WindowImpl::WindowImpl()
+    : window_style_(0),
+      window_ex_style_(kWindowDefaultExStyle),
+      class_style_(CS_DBLCLKS),
+      hwnd_(NULL) {
+}
+
+WindowImpl::~WindowImpl() {
+}
+
+void WindowImpl::Init(HWND parent, const gfx::Rect& bounds) {
+  if (window_style_ == 0)
+    window_style_ = parent ? kWindowDefaultChildStyle : kWindowDefaultStyle;
+
+  // Ensures the parent we have been passed is valid, otherwise CreateWindowEx
+  // will fail.
+  if (parent && !::IsWindow(parent)) {
+    NOTREACHED() << "invalid parent window specified.";
+    parent = NULL;
+  }
+
+  int x, y, width, height;
+  if (bounds.IsEmpty()) {
+    x = y = width = height = CW_USEDEFAULT;
+  } else {
+    x = bounds.x();
+    y = bounds.y();
+    width = bounds.width();
+    height = bounds.height();
+  }
+
+  hwnd_ = CreateWindowEx(window_ex_style_, GetWindowClassName().c_str(), NULL,
+                         window_style_, x, y, width, height,
+                         parent, NULL, NULL, this);
+  DCHECK(hwnd_);
+
+  // The window procedure should have set the data for us.
+  DCHECK(win_util::GetWindowUserData(hwnd_) == this);
+}
+
+HICON WindowImpl::GetDefaultWindowIcon() const {
+  return NULL;
+}
+
+// static
+bool WindowImpl::IsWindowImpl(HWND hwnd) {
+  wchar_t tmp[128];
+  if (!::GetClassName(hwnd, tmp, 128))
+    return false;
+
+  std::wstring class_name(tmp);
+  return class_name.find(kBaseClassName) == 0;
+}
+
+LRESULT WindowImpl::OnWndProc(UINT message, WPARAM w_param, LPARAM l_param) {
+  LRESULT result = 0;
+
+  // Handle the message if it's in our message map; otherwise, let the system
+  // handle it.
+  if (!ProcessWindowMessage(hwnd_, message, w_param, l_param, result))
+    result = DefWindowProc(hwnd_, message, w_param, l_param);
+
+  return result;
+}
+
+// static
+LRESULT CALLBACK WindowImpl::WndProc(HWND hwnd,
+                                     UINT message,
+                                     WPARAM w_param,
+                                     LPARAM l_param) {
+  if (message == WM_NCCREATE) {
+    CREATESTRUCT* cs = reinterpret_cast<CREATESTRUCT*>(l_param);
+    WindowImpl* window = reinterpret_cast<WindowImpl*>(cs->lpCreateParams);
+    DCHECK(window);
+    win_util::SetWindowUserData(hwnd, window);
+    window->hwnd_ = hwnd;
+    return TRUE;
+  }
+
+  WindowImpl* window = reinterpret_cast<WindowImpl*>(
+      win_util::GetWindowUserData(hwnd));
+  if (!window)
+    return 0;
+
+  return window->OnWndProc(message, w_param, l_param);
+}
+
+std::wstring WindowImpl::GetWindowClassName() {
+  ClassInfo class_info(initial_class_style());
+  std::wstring name;
+  if (Singleton<ClassRegistrar>()->RetrieveClassName(class_info, &name))
+    return name;
+
+  // No class found, need to register one.
+  WNDCLASSEX class_ex;
+  class_ex.cbSize = sizeof(WNDCLASSEX);
+  class_ex.style = class_info.style;
+  class_ex.lpfnWndProc = &WindowImpl::WndProc;
+  class_ex.cbClsExtra = 0;
+  class_ex.cbWndExtra = 0;
+  class_ex.hInstance = NULL;
+  class_ex.hIcon = GetDefaultWindowIcon();
+  class_ex.hCursor = LoadCursor(NULL, IDC_ARROW);
+  class_ex.hbrBackground = reinterpret_cast<HBRUSH>(class_info.background + 1);
+  class_ex.lpszMenuName = NULL;
+  class_ex.lpszClassName = name.c_str();
+  class_ex.hIconSm = class_ex.hIcon;
+  ATOM atom = RegisterClassEx(&class_ex);
+  DCHECK(atom);
+
+  Singleton<ClassRegistrar>()->RegisterClass(class_info, name, atom);
+
+  return name;
+}
+
+}  // namespace gfx
diff --git a/gfx/window_impl.h b/gfx/window_impl.h
new file mode 100644
index 0000000..228e9096
--- /dev/null
+++ b/gfx/window_impl.h
@@ -0,0 +1,113 @@
+// Copyright (c) 2010 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.
+
+#ifndef GFX_WINDOW_IMPL_H_
+#define GFX_WINDOW_IMPL_H_
+
+#include <atlbase.h>
+#include <atlapp.h>
+#include <atlmisc.h>
+#include <atlcrack.h>
+
+#include <string>
+
+#include "base/logging.h"
+#include "gfx/native_widget_types.h"
+#include "gfx/rect.h"
+
+namespace gfx {
+
+// An interface implemented by classes that use message maps.
+// ProcessWindowMessage is implemented by the BEGIN_MESSAGE_MAP_EX macro.
+class MessageMapInterface {
+ public:
+  // Processes one message from the window's message queue.
+  virtual BOOL ProcessWindowMessage(HWND window,
+                                    UINT message,
+                                    WPARAM w_param,
+                                    LPARAM l_param,
+                                    LRESULT& result,
+                                    DWORD msg_mad_id = 0) = 0;
+};
+
+///////////////////////////////////////////////////////////////////////////////
+//
+// WindowImpl
+//  A convenience class that encapsulates the details of creating and
+//  destroying a HWND.  This class also hosts the windows procedure used by all
+//  Windows.
+//
+///////////////////////////////////////////////////////////////////////////////
+class WindowImpl : public MessageMapInterface {
+ public:
+  WindowImpl();
+  virtual ~WindowImpl();
+
+  // Initializes the Window with a parent and an initial desired size.
+  void Init(HWND parent, const gfx::Rect& bounds);
+
+  // Retrieves the default window icon to use for windows if none is specified.
+  virtual HICON GetDefaultWindowIcon() const;
+
+  // Returns the HWND associated with this Window.
+  HWND hwnd() const { return hwnd_; }
+
+  // Sets the window styles. This is ONLY used when the window is created.
+  // In other words, if you invoke this after invoking Init, nothing happens.
+  void set_window_style(DWORD style) { window_style_ = style; }
+  DWORD window_style() const { return window_style_; }
+
+  // Sets the extended window styles. See comment about |set_window_style|.
+  void set_window_ex_style(DWORD style) { window_ex_style_ = style; }
+  DWORD window_ex_style() const { return window_ex_style_; }
+
+  // Sets the class style to use. The default is CS_DBLCLKS.
+  void set_initial_class_style(UINT class_style) {
+    // We dynamically generate the class name, so don't register it globally!
+    DCHECK_EQ((class_style & CS_GLOBALCLASS), 0u);
+    class_style_ = class_style;
+  }
+  UINT initial_class_style() const { return class_style_; }
+
+  // Returns true if the specified |hwnd| is a WindowImpl.
+  static bool IsWindowImpl(HWND hwnd);
+
+ protected:
+  // Handles the WndProc callback for this object.
+  virtual LRESULT OnWndProc(UINT message, WPARAM w_param, LPARAM l_param);
+
+ private:
+  friend class ClassRegistrar;
+
+  // The window procedure used by all Windows.
+  static LRESULT CALLBACK WndProc(HWND window,
+                                  UINT message,
+                                  WPARAM w_param,
+                                  LPARAM l_param);
+
+  // Gets the window class name to use when creating the corresponding HWND.
+  // If necessary, this registers the window class.
+  std::wstring GetWindowClassName();
+
+  // All classes registered by WidgetWin start with this name.
+  static const wchar_t* const kBaseClassName;
+
+  // Window Styles used when creating the window.
+  DWORD window_style_;
+
+  // Window Extended Styles used when creating the window.
+  DWORD window_ex_style_;
+
+  // Style of the class to use.
+  UINT class_style_;
+
+  // Our hwnd.
+  HWND hwnd_;
+
+  DISALLOW_COPY_AND_ASSIGN(WindowImpl);
+};
+
+}  // namespace gfx
+
+#endif  // GFX_WINDOW_IMPL_H_