Functional prefs implementation

shell/src/PrefsCommand.cpp

Index: shell/src/PrefsCommand.cpp
===================================================================
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+++ b/shell/src/PrefsCommand.cpp
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+/*
+ * This file is part of Adblock Plus <http://adblockplus.org/>,
+ * Copyright (C) 2006-2013 Eyeo GmbH
+ *
+ * Adblock Plus is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 3 as
+ * published by the Free Software Foundation.
+ *
+ * Adblock Plus is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with Adblock Plus.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include <iostream>
+#include <sstream>
+
+#include "PrefsCommand.h"
+
+PrefsCommand::PrefsCommand(AdblockPlus::FilterEngine& filterEngine)
+  : Command("prefs"), filterEngine(filterEngine)
+{
+}
+
+void PrefsCommand::operator()(const std::string& arguments)
+{
+  std::istringstream argumentStream(arguments);
+  std::string action;
+  argumentStream >> action;
+  if (!action.size())
+  {
+    ShowUsage();
+    return;
+  }
+
+  if (action == "show")
+  {
+    std::string pref;
+    argumentStream >> pref;
+
+    AdblockPlus::JsValuePtr value = filterEngine.GetPref(pref);
+    if (value->IsUndefined())
+      std::cout << "No such preference" << std::endl;
+    else
+    {
+      if (value->IsString())
+        std::cout << "(string) ";
+      else if (value->IsNumber())
+        std::cout << "(number) ";
+      else if (value->IsBool())
+        std::cout << "(bool) ";
+      else
+        std::cout << "(unknown type) ";
+      std::cout << value->AsString() << std::endl;
+    }
+  }
+  else if (action == "set")
+  {
+    std::string pref;
+    argumentStream >> pref;
+
+    AdblockPlus::JsValuePtr current = filterEngine.GetPref(pref);
+    if (current->IsUndefined())
+      std::cout << "No such preference" << std::endl;
+    else if (current->IsString())
+    {
+      std::string value;
+      std::getline(argumentStream, value);
+      filterEngine.SetPref(pref, filterEngine.GetJsEngine()->NewValue(value));
+    }
+    else if (current->IsNumber())
+    {
+      int64_t value;
+      argumentStream >> value;
+      filterEngine.SetPref(pref, filterEngine.GetJsEngine()->NewValue(value));
+    }
+    else if (current->IsBool())
+    {
+      bool value;
+      argumentStream >> value;
+      filterEngine.SetPref(pref, filterEngine.GetJsEngine()->NewValue(value));
+    }
+    else
+      std::cout << "Cannot set a preference of unknown type" << std::endl;
+  }
+  else
+    throw NoSuchCommandError(name + " " + action);
+}
+
+std::string PrefsCommand::GetDescription() const
+{
+  return "Get and set preferences";
+}
+
+std::string PrefsCommand::GetUsage() const
+{
+  return name + " [show PREF|set PREF VALUE]";
+}