Printing: Convert PrintingContext into an interface implemented by the separate

printing/printing_context_win.h

+// 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 PRINTING_PRINTING_CONTEXT_WIN_H_
+#define PRINTING_PRINTING_CONTEXT_WIN_H_
+
+#include <ocidl.h>
+#include <commdlg.h>
+
+#include <string>
+
+#include "base/scoped_ptr.h"
+#include "build/build_config.h"
+#include "gfx/native_widget_types.h"
+#include "printing/printing_context.h"
+
+namespace printing {
+
+class PrintingContextWin : public PrintingContext {
+ public:
+  PrintingContextWin();
+  ~PrintingContextWin();
+
+  // PrintingContext implementation.
+  virtual void AskUserForSettings(gfx::NativeView parent_view,
+                                  int max_pages,
+                                  bool has_selection,
+                                  PrintSettingsCallback* callback);
+  virtual Result UseDefaultSettings();
+  virtual Result InitWithSettings(const PrintSettings& settings);
+  virtual Result NewDocument(const string16& document_name);
+  virtual Result NewPage();
+  virtual Result PageDone();
+  virtual Result DocumentDone();
+  virtual void Cancel();
+  virtual void DismissDialog();
+  virtual void ReleaseContext();
+  virtual gfx::NativeDrawingContext context() const;
+
+#if defined(UNIT_TEST)
+  // Sets a fake PrintDlgEx function pointer in tests.
+  void SetPrintDialog(HRESULT (__stdcall *print_dialog_func)(LPPRINTDLGEX)) {
+    print_dialog_func_ = print_dialog_func;
+  }
+#endif  // defined(UNIT_TEST)
+
+  // Allocates the HDC for a specific DEVMODE.
+  static bool AllocateContext(const std::wstring& printer_name,
+                              const DEVMODE* dev_mode,
+                              gfx::NativeDrawingContext* context);
+
+  // Retrieves the content of a GetPrinter call.
+  static void GetPrinterHelper(HANDLE printer, int level,
+                               scoped_array<uint8>* buffer);
+
+ private:
+  // Class that manages the PrintDlgEx() callbacks. This is meant to be a
+  // temporary object used during the Print... dialog display.
+  class CallbackHandler;
+
+  // Used in response to the user canceling the printing.
+  static BOOL CALLBACK AbortProc(HDC hdc, int nCode);
+
+  // Reads the settings from the selected device context. Updates settings_ and
+  // its margins.
+  bool InitializeSettings(const DEVMODE& dev_mode,
+                          const std::wstring& new_device_name,
+                          const PRINTPAGERANGE* ranges,
+                          int number_ranges,
+                          bool selection_only);
+
+  // Retrieves the printer's default low-level settings. On Windows, context_ is
+  // allocated with this call.
+  bool GetPrinterSettings(HANDLE printer,
+                          const std::wstring& device_name);
+
+  // Parses the result of a PRINTDLGEX result.
+  Result ParseDialogResultEx(const PRINTDLGEX& dialog_options);
+  Result ParseDialogResult(const PRINTDLG& dialog_options);
+
+  // The selected printer context.
+  HDC context_;
+
+  // The dialog box for the time it is shown.
+  volatile HWND dialog_box_;
+
+  // Function pointer that defaults to PrintDlgEx. It can be changed using
+  // SetPrintDialog() in tests.
+  HRESULT (__stdcall *print_dialog_func_)(LPPRINTDLGEX);
+
+  DISALLOW_COPY_AND_ASSIGN(PrintingContextWin);
+};
+
+}  // namespace printing
+
+#endif  // PRINTING_PRINTING_CONTEXT_WIN_H_