Implement Printer Preference Persistence (Step 1/3)

Introduce new "Preferences" for printer overlays were added in PrefNames:  
- printing.page.header.left  
- printing.page.header.center 
- printing.page.header.right 
- printing.page.footer.left 
- printing.page.footer.center 
- printing.page.footer.right

The prefs file will look like this:

"printing": {
   "page": {
      "header": {
         "left": " ",
         "center": " ",
         "right": " "
      },
      "footer": {
         "left": "{date}",
         "center": " ",
         "right": " "
      }
   }
}

The steps for Printer Preferences:

Step 1:
 Introduce some sort of persistence for header/footer which is located 
in the Preference file.

Step 2:
 Allow PrinterQuery to read those stored preferences and setup 
PrinterSettings so that it will apply it when printing.

Step 3:
 Create a UI for the print preference, so that the users will easily 
change those printing settings.

NOTE: I tested the following approach while doing a simple Hack with 
PrintJob (if you see the previous patch), and it works great, with some 
bad after effect.
It was done for testing purposes. So I hope we are going in the right
direction.

BUG=947 (http://crbug.com/947)

Patch contributed by Mohamed Mansour <m0.interactive@gmail.com>

Review: http://codereview.chromium.org/60118/show

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@13426 0039d316-1c4b-4281-b951-d872f2087c98

3 files changed, 68 insertions, 3 deletions

diff --git a/chrome/browser/printing/page_overlays.cc b/chrome/browser/printing/page_overlays.cc
index eb1d3c6..4a20dd6 100644
--- a/chrome/browser/printing/page_overlays.cc
+++ b/chrome/browser/printing/page_overlays.cc
@@ -1,4 +1,4 @@
-// Copyright (c) 2006-2008 The Chromium Authors. All rights reserved.
+// Copyright (c) 2006-2009 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.
 
@@ -84,6 +84,54 @@ const std::wstring& PageOverlays::GetOverlay(HorizontalPosition x,
   return EmptyWString();
 }
 
+void PageOverlays::SetOverlay(HorizontalPosition x, VerticalPosition y,
+                              std::wstring& input) {
+  switch (x) {
+    case LEFT:
+      switch (y) {
+        case TOP:
+          top_left = input;
+          break;
+        case BOTTOM:
+          bottom_left = input;
+          break;
+        default:
+          NOTREACHED();
+          break;
+      }
+      break;
+    case CENTER:
+      switch (y) {
+        case TOP:
+          top_center = input;
+          break;
+        case BOTTOM:
+          bottom_center = input;
+          break;
+        default:
+          NOTREACHED();
+          break;
+      }
+      break;
+    case RIGHT:
+      switch (y) {
+        case TOP:
+          top_right = input;
+          break;
+        case BOTTOM:
+          bottom_right = input;
+          break;
+        default:
+          NOTREACHED();
+          break;
+      }
+      break;
+    default:
+      NOTREACHED();
+      break;
+  }
+}
+
 //static
 std::wstring PageOverlays::ReplaceVariables(const std::wstring& input,
                                             const PrintedDocument& document,
diff --git a/chrome/browser/printing/page_overlays.h b/chrome/browser/printing/page_overlays.h
index 42e77fc..7663153 100644
--- a/chrome/browser/printing/page_overlays.h
+++ b/chrome/browser/printing/page_overlays.h
@@ -1,4 +1,4 @@
-// Copyright (c) 2006-2008 The Chromium Authors. All rights reserved.
+// Copyright (c) 2006-2009 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.
 
@@ -39,6 +39,10 @@ class PageOverlays {
   const std::wstring& GetOverlay(HorizontalPosition x,
                                  VerticalPosition y) const;
 
+  // Sets the string of an overlay according to its x,y position.
+  void SetOverlay(HorizontalPosition x, VerticalPosition y,
+                  std::wstring& input);
+
   // Replaces the variables in |input| with their actual values according to the
   // properties of the current printed document and the current printed page.
   static std::wstring ReplaceVariables(const std::wstring& input,
diff --git a/chrome/browser/printing/page_overlays_unittest.cc b/chrome/browser/printing/page_overlays_unittest.cc
index 04104a8..0710f33 100644
--- a/chrome/browser/printing/page_overlays_unittest.cc
+++ b/chrome/browser/printing/page_overlays_unittest.cc
@@ -1,4 +1,4 @@
-// Copyright (c) 2006-2008 The Chromium Authors. All rights reserved.
+// Copyright (c) 2006-2009 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.
 
@@ -73,4 +73,17 @@ TEST_F(PageOverlaysTest, StringConversion) {
     EXPECT_EQ(StringPrintf(L"foo%lsbar", kOverlayKeys[i].expected), out) <<
         kOverlayKeys[i].key;
   }
+
+  // Check if SetOverlay really sets the page overlay.
+  overlays.SetOverlay(printing::PageOverlays::LEFT,
+                      printing::PageOverlays::TOP,
+                      UTF16ToWide(L"Page {page}"));
+  input = overlays.GetOverlay(printing::PageOverlays::LEFT,
+                              printing::PageOverlays::TOP);
+  EXPECT_EQ(input, L"Page {page}");
+
+  // Replace the variables to see if the page number is correct.
+  out = printing::PageOverlays::ReplaceVariables(input, *doc.get(),
+                                                 *page.get());
+  EXPECT_EQ(out, L"Page 1");
 }