// 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/net/proxy_service_factory.h"

#include "base/command_line.h"
#include "base/strings/string_number_conversions.h"
#include "base/threading/thread.h"
#include "chrome/browser/browser_process.h"
#include "chrome/browser/io_thread.h"
#include "chrome/browser/net/pref_proxy_config_tracker_impl.h"
#include "chrome/common/chrome_switches.h"
#include "content/public/browser/browser_thread.h"
#include "net/base/net_log.h"
#include "net/proxy/dhcp_proxy_script_fetcher_factory.h"
#include "net/proxy/proxy_config_service.h"
#include "net/proxy/proxy_script_fetcher_impl.h"
#include "net/proxy/proxy_service.h"
#include "net/proxy/proxy_service_v8.h"
#include "net/url_request/url_request_context.h"

#if defined(OS_CHROMEOS)
#include "chrome/browser/chromeos/proxy_config_service_impl.h"
#include "chromeos/network/dhcp_proxy_script_fetcher_chromeos.h"
#endif  // defined(OS_CHROMEOS)

#if defined(OS_WIN)
#include "win8/util/win8_util.h"
#endif

using content::BrowserThread;

// static
net::ProxyConfigService* ProxyServiceFactory::CreateProxyConfigService(
    PrefProxyConfigTracker* tracker) {
  // The linux gconf-based proxy settings getter relies on being initialized
  // from the UI thread.
  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));

  scoped_ptr<net::ProxyConfigService> base_service;

#if !defined(OS_CHROMEOS)
  // On ChromeOS, base service is NULL; chromeos::ProxyConfigServiceImpl
  // determines the effective proxy config to take effect in the network layer,
  // be it from prefs or system (which is network shill on chromeos).

  // For other platforms, create a baseline service that provides proxy
  // configuration in case nothing is configured through prefs (Note: prefs
  // include command line and configuration policy).

  // TODO(port): the IO and FILE message loops are only used by Linux.  Can
  // that code be moved to chrome/browser instead of being in net, so that it
  // can use BrowserThread instead of raw MessageLoop pointers? See bug 25354.
  base_service.reset(net::ProxyService::CreateSystemProxyConfigService(
      BrowserThread::GetMessageLoopProxyForThread(BrowserThread::IO).get(),
      BrowserThread::UnsafeGetMessageLoopForThread(BrowserThread::FILE)));
#endif  // !defined(OS_CHROMEOS)

  return tracker->CreateTrackingProxyConfigService(base_service.Pass())
      .release();
}

// static
PrefProxyConfigTracker*
ProxyServiceFactory::CreatePrefProxyConfigTrackerOfProfile(
    PrefService* profile_prefs,
    PrefService* local_state_prefs) {
#if defined(OS_CHROMEOS)
  return new chromeos::ProxyConfigServiceImpl(profile_prefs, local_state_prefs);
#else
  return new PrefProxyConfigTrackerImpl(profile_prefs);
#endif  // defined(OS_CHROMEOS)
}

// static
PrefProxyConfigTracker*
ProxyServiceFactory::CreatePrefProxyConfigTrackerOfLocalState(
    PrefService* local_state_prefs) {
#if defined(OS_CHROMEOS)
  return new chromeos::ProxyConfigServiceImpl(NULL, local_state_prefs);
#else
  return new PrefProxyConfigTrackerImpl(local_state_prefs);
#endif  // defined(OS_CHROMEOS)
}

// static
net::ProxyService* ProxyServiceFactory::CreateProxyService(
    net::NetLog* net_log,
    net::URLRequestContext* context,
    net::NetworkDelegate* network_delegate,
    net::ProxyConfigService* proxy_config_service,
    const CommandLine& command_line) {
  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::IO));

#if defined(OS_IOS)
  bool use_v8 = false;
#else
  bool use_v8 = !command_line.HasSwitch(switches::kWinHttpProxyResolver);
  if (use_v8 && command_line.HasSwitch(switches::kSingleProcess)) {
    // See the note about V8 multithreading in net/proxy/proxy_resolver_v8.h
    // to understand why we have this limitation.
    LOG(ERROR) << "Cannot use V8 Proxy resolver in single process mode.";
    use_v8 = false;  // Fallback to non-v8 implementation.
  }
#endif  // defined(OS_IOS)

#if defined(OS_WIN)
  // Crashes. http://crbug.com/266838
  if (use_v8 && win8::IsSingleWindowMetroMode())
    use_v8 = false;
#endif

  size_t num_pac_threads = 0u;  // Use default number of threads.

  // Check the command line for an override on the number of proxy resolver
  // threads to use.
  if (command_line.HasSwitch(switches::kNumPacThreads)) {
    std::string s = command_line.GetSwitchValueASCII(switches::kNumPacThreads);

    // Parse the switch (it should be a positive integer formatted as decimal).
    int n;
    if (base::StringToInt(s, &n) && n > 0) {
      num_pac_threads = static_cast<size_t>(n);
    } else {
      LOG(ERROR) << "Invalid switch for number of PAC threads: " << s;
    }
  }

  net::ProxyService* proxy_service = NULL;
  if (use_v8) {
#if defined(OS_IOS)
    NOTREACHED();
#else
    net::DhcpProxyScriptFetcher* dhcp_proxy_script_fetcher;
#if defined(OS_CHROMEOS)
    dhcp_proxy_script_fetcher =
        new chromeos::DhcpProxyScriptFetcherChromeos(context);
#else
    net::DhcpProxyScriptFetcherFactory dhcp_factory;
    if (command_line.HasSwitch(switches::kDisableDhcpWpad))
      dhcp_factory.set_enabled(false);
    dhcp_proxy_script_fetcher = dhcp_factory.Create(context);
#endif

    proxy_service = net::CreateProxyServiceUsingV8ProxyResolver(
        proxy_config_service,
        new net::ProxyScriptFetcherImpl(context),
        dhcp_proxy_script_fetcher,
        context->host_resolver(),
        net_log,
        network_delegate);
#endif  // defined(OS_IOS)
  } else {
    proxy_service = net::ProxyService::CreateUsingSystemProxyResolver(
        proxy_config_service,
        num_pac_threads,
        net_log);
  }

  return proxy_service;
}