Print Preview: Implement basic settings.

BUG=57902
TEST=Run with --enable-print-preview, make sure orientation and color settings work.
Review URL: http://codereview.chromium.org/6736014

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@79655 0039d316-1c4b-4281-b951-d872f2087c98

2 files changed, 56 insertions, 2 deletions

diff --git a/chrome/browser/ui/webui/print_preview_handler.cc b/chrome/browser/ui/webui/print_preview_handler.cc
index 45f316b..b828070 100644
--- a/chrome/browser/ui/webui/print_preview_handler.cc
+++ b/chrome/browser/ui/webui/print_preview_handler.cc
@@ -15,9 +15,13 @@
 #include "content/browser/renderer_host/render_view_host.h"
 #include "content/browser/tab_contents/tab_contents.h"
 #include "printing/backend/print_backend.h"
+#include "printing/print_job_constants.h"
 
 namespace {
 
+const bool kColorDefaultValue = false;
+const bool kLandscapeDefaultValue = false;
+
 TabContents* GetInitiatorTab(TabContents* preview_tab) {
   printing::PrintPreviewTabController* tab_controller =
       printing::PrintPreviewTabController::GetInstance();
@@ -26,6 +30,8 @@ TabContents* GetInitiatorTab(TabContents* preview_tab) {
   return tab_controller->GetInitiatorTab(preview_tab);
 }
 
+// Get the print job settings dictionary from |args|. The caller takes
+// ownership of the returned DictionaryValue. Returns NULL on failure.
 DictionaryValue* GetSettingsDictionary(const ListValue* args) {
   std::string json_str;
   if (!args->GetString(0, &json_str)) {
@@ -100,7 +106,10 @@ class EnumeratePrintersTaskProxy
 };
 
 PrintPreviewHandler::PrintPreviewHandler()
-    : print_backend_(printing::PrintBackend::CreateInstance(NULL)) {
+    : print_backend_(printing::PrintBackend::CreateInstance(NULL)),
+      need_to_generate_preview_(true),
+      color_(kColorDefaultValue),
+      landscape_(kLandscapeDefaultValue) {
 }
 
 PrintPreviewHandler::~PrintPreviewHandler() {
@@ -131,7 +140,17 @@ void PrintPreviewHandler::HandleGetPreview(const ListValue* args) {
   scoped_ptr<DictionaryValue> settings(GetSettingsDictionary(args));
   if (!settings.get())
     return;
-  initiator_tab->render_view_host()->PrintPreview(*settings);
+
+  // Handle settings that do not require print preview regeneration.
+  ProcessColorSetting(*settings);
+
+  // Handle settings that require print preview regeneration.
+  ProcessLandscapeSetting(*settings);
+
+  if (need_to_generate_preview_) {
+    initiator_tab->render_view_host()->PrintPreview(*settings);
+    need_to_generate_preview_ = false;
+  }
 }
 
 void PrintPreviewHandler::HandlePrint(const ListValue* args) {
@@ -150,3 +169,23 @@ void PrintPreviewHandler::HandlePrint(const ListValue* args) {
 void PrintPreviewHandler::SendPrinterList(const ListValue& printers) {
   web_ui_->CallJavascriptFunction("setPrinters", printers);
 }
+
+void PrintPreviewHandler::ProcessColorSetting(const DictionaryValue& settings) {
+  bool color = kColorDefaultValue;
+  settings.GetBoolean(printing::kSettingColor, &color);
+  if (color != color_) {
+    color_ = color;
+    FundamentalValue color_value(color_);
+    web_ui_->CallJavascriptFunction("setColor", color_value);
+  }
+}
+
+void PrintPreviewHandler::ProcessLandscapeSetting(
+    const DictionaryValue& settings) {
+  bool landscape = kLandscapeDefaultValue;
+  settings.GetBoolean(printing::kSettingLandscape, &landscape);
+  if (landscape != landscape_) {
+    landscape_ = landscape;
+    need_to_generate_preview_ = true;
+  }
+}
diff --git a/chrome/browser/ui/webui/print_preview_handler.h b/chrome/browser/ui/webui/print_preview_handler.h
index 9f11707..108234e 100644
--- a/chrome/browser/ui/webui/print_preview_handler.h
+++ b/chrome/browser/ui/webui/print_preview_handler.h
@@ -43,9 +43,24 @@ class PrintPreviewHandler : public WebUIMessageHandler,
   // Send the list of printers to the Web UI.
   void SendPrinterList(const ListValue& printers);
 
+  // Helper function to process the color setting in the dictionary.
+  void ProcessColorSetting(const DictionaryValue& settings);
+
+  // Helper function to process the landscape setting in the dictionary.
+  void ProcessLandscapeSetting(const DictionaryValue& settings);
+
   // Pointer to current print system.
   scoped_refptr<printing::PrintBackend> print_backend_;
 
+  // Set to true if we need to generate a new print preview.
+  bool need_to_generate_preview_;
+
+  // Set to true if the preview should be in color.
+  bool color_;
+
+  // Set to true if the preview should be landscape.
+  bool landscape_;
+
   DISALLOW_COPY_AND_ASSIGN(PrintPreviewHandler);
 };