// Copyright 2014 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 "extensions/browser/extension_function_registry.h"

#include "base/memory/singleton.h"
#include "extensions/browser/extension_function.h"
#include "extensions/browser/extensions_browser_client.h"

// static
ExtensionFunctionRegistry* ExtensionFunctionRegistry::GetInstance() {
  return base::Singleton<ExtensionFunctionRegistry>::get();
}

ExtensionFunctionRegistry::ExtensionFunctionRegistry() {
  extensions::ExtensionsBrowserClient* client =
      extensions::ExtensionsBrowserClient::Get();
  if (client) {
    client->RegisterExtensionFunctions(this);
  }
}

ExtensionFunctionRegistry::~ExtensionFunctionRegistry() {}

bool ExtensionFunctionRegistry::OverrideFunction(
    const std::string& name,
    ExtensionFunctionFactory factory) {
  FactoryMap::iterator iter = factories_.find(name);
  if (iter == factories_.end()) {
    return false;
  } else {
    iter->second.factory_ = factory;
    return true;
  }
}

ExtensionFunction* ExtensionFunctionRegistry::NewFunction(
    const std::string& name) {
  FactoryMap::iterator iter = factories_.find(name);
  if (iter == factories_.end()) {
    return NULL;
  }
  ExtensionFunction* function = iter->second.factory_();
  function->set_name(iter->second.function_name_);
  function->set_histogram_value(iter->second.histogram_value_);
  return function;
}

ExtensionFunctionRegistry::FactoryEntry::FactoryEntry()
    : factory_(0),
      function_name_(nullptr),
      histogram_value_(extensions::functions::UNKNOWN) {
}

ExtensionFunctionRegistry::FactoryEntry::FactoryEntry(
    ExtensionFunctionFactory factory,
    const char* function_name,
    extensions::functions::HistogramValue histogram_value)
    : factory_(factory),
      function_name_(function_name),
      histogram_value_(histogram_value) {
}