// Copyright (c) 2012 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 "chrome/browser/plugin_finder.h"

#include "base/bind.h"
#include "base/json/json_reader.h"
#include "base/message_loop.h"
#include "base/stl_util.h"
#include "base/values.h"
#include "chrome/browser/browser_process.h"
#include "chrome/browser/plugin_installer.h"
#include "chrome/browser/prefs/pref_service.h"
#include "chrome/common/pref_names.h"
#include "content/public/browser/browser_thread.h"
#include "googleurl/src/gurl.h"
#include "grit/browser_resources.h"
#include "ui/base/resource/resource_bundle.h"

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

PluginFinder::PluginFinder() : plugin_list_(LoadPluginList()) {
  if (!plugin_list_.get()) {
    NOTREACHED();
    plugin_list_.reset(new base::ListValue());
  }
}

// static
scoped_ptr<base::ListValue> PluginFinder::LoadPluginList() {
  return scoped_ptr<base::ListValue>(LoadPluginListInternal()).Pass();
}

base::ListValue* PluginFinder::LoadPluginListInternal() {
#if defined(OS_WIN) || defined(OS_MACOSX) || defined(OS_LINUX)
  base::StringPiece json_resource(
      ResourceBundle::GetSharedInstance().GetRawDataResource(
          IDR_PLUGIN_DB_JSON));
  bool allow_trailing_comma = false;
  std::string error_str;
  scoped_ptr<base::Value> value(base::JSONReader::ReadAndReturnError(
      json_resource.as_string(),
      allow_trailing_comma,
      NULL,
      &error_str));
  if (!value.get()) {
    DLOG(ERROR) << error_str;
    return NULL;
  }
  base::DictionaryValue* dict = NULL;
  if (!value->GetAsDictionary(&dict))
    return NULL;
  base::ListValue* list = NULL;
  if (!dict->GetList("plugins", &list))
    return NULL;
  return list->DeepCopy();
#else
  return new base::ListValue();
#endif
}

PluginFinder::~PluginFinder() {
  STLDeleteValues(&installers_);
}

void PluginFinder::FindPlugin(
    const std::string& mime_type,
    const std::string& language,
    const FindPluginCallback& callback) {
  PluginInstaller* installer = FindPluginInternal(mime_type, language);
  MessageLoop::current()->PostTask(FROM_HERE, base::Bind(callback, installer));
}

void PluginFinder::FindPluginWithIdentifier(
    const std::string& identifier,
    const FindPluginCallback& found_callback) {
  PluginInstaller* installer = NULL;
  std::map<std::string, PluginInstaller*>::const_iterator it =
      installers_.find(identifier);
  if (it != installers_.end()) {
    installer = it->second;
  } else {
    for (ListValue::const_iterator plugin_it = plugin_list_->begin();
         plugin_it != plugin_list_->end(); ++plugin_it) {
      const base::DictionaryValue* plugin = NULL;
      if (!(*plugin_it)->GetAsDictionary(&plugin)) {
        NOTREACHED();
        continue;
      }
      std::string id;
      bool success = plugin->GetString("identifier", &id);
      DCHECK(success);
      if (id == identifier) {
        installer = CreateInstaller(identifier, plugin);
        break;
      }
    }
  }
  MessageLoop::current()->PostTask(FROM_HERE,
                                   base::Bind(found_callback, installer));
}

PluginInstaller* PluginFinder::CreateInstaller(
    const std::string& identifier,
    const base::DictionaryValue* plugin_dict) {
  DCHECK(!installers_[identifier]);
  std::string url;
  bool success = plugin_dict->GetString("url", &url);
  DCHECK(success);
  std::string help_url;
  plugin_dict->GetString("help_url", &help_url);
  string16 name;
  success = plugin_dict->GetString("name", &name);
  DCHECK(success);
  bool display_url = false;
  plugin_dict->GetBoolean("displayurl", &display_url);
  PluginInstaller*installer = new PluginInstaller(identifier,
                                                  GURL(url),
                                                  GURL(help_url),
                                                  name,
                                                  display_url);
  installers_[identifier] = installer;
  return installer;
}

PluginInstaller* PluginFinder::FindPluginInternal(
    const std::string& mime_type,
    const std::string& language) {
  if (!g_browser_process->local_state()->GetBoolean(
          prefs::kDisablePluginFinder)) {
    for (ListValue::const_iterator plugin_it = plugin_list_->begin();
         plugin_it != plugin_list_->end(); ++plugin_it) {
      const base::DictionaryValue* plugin = NULL;
      if (!(*plugin_it)->GetAsDictionary(&plugin)) {
        NOTREACHED();
        continue;
      }
      std::string language_str;
      bool success = plugin->GetString("lang", &language_str);
      DCHECK(success);
      if (language_str != language)
        continue;
      ListValue* mime_types = NULL;
      success = plugin->GetList("mime_types", &mime_types);
      DCHECK(success);
      for (ListValue::const_iterator mime_type_it = mime_types->begin();
           mime_type_it != mime_types->end(); ++mime_type_it) {
        std::string mime_type_str;
        success = (*mime_type_it)->GetAsString(&mime_type_str);
        DCHECK(success);
        if (mime_type_str == mime_type) {
          std::string identifier;
          bool success = plugin->GetString("identifier", &identifier);
          DCHECK(success);
          std::map<std::string, PluginInstaller*>::const_iterator it =
              installers_.find(identifier);
          if (it != installers_.end())
            return it->second;
          return CreateInstaller(identifier, plugin);
        }
      }
    }
  }
  return NULL;
}