[Popular Sites] Move PopularSitesImpl to dedicated file

components/ntp_tiles/popular_sites.cc

Index: components/ntp_tiles/popular_sites.cc
diff --git a/components/ntp_tiles/popular_sites.cc b/components/ntp_tiles/popular_sites.cc
deleted file mode 100644
index 0917a14a47768709519b10820c0909154abcb20c..0000000000000000000000000000000000000000
--- a/components/ntp_tiles/popular_sites.cc
+++ /dev/null
@@ -1,398 +0,0 @@
-// Copyright 2015 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 "components/ntp_tiles/popular_sites.h"
-
-#include <stddef.h>
-
-#include "base/bind.h"
-#include "base/command_line.h"
-#include "base/files/file_path.h"
-#include "base/files/file_util.h"
-#include "base/files/important_file_writer.h"
-#include "base/json/json_reader.h"
-#include "base/json/json_writer.h"
-#include "base/path_service.h"
-#include "base/strings/string_util.h"
-#include "base/strings/stringprintf.h"
-#include "base/task_runner_util.h"
-#include "base/time/time.h"
-#include "base/values.h"
-#include "components/data_use_measurement/core/data_use_user_data.h"
-#include "components/google/core/browser/google_util.h"
-#include "components/ntp_tiles/constants.h"
-#include "components/ntp_tiles/pref_names.h"
-#include "components/ntp_tiles/switches.h"
-#include "components/pref_registry/pref_registry_syncable.h"
-#include "components/prefs/pref_service.h"
-#include "components/search_engines/search_engine_type.h"
-#include "components/search_engines/template_url_service.h"
-#include "components/variations/service/variations_service.h"
-#include "components/variations/variations_associated_data.h"
-#include "net/base/load_flags.h"
-#include "net/http/http_status_code.h"
-
-#if defined(OS_IOS)
-#include "components/ntp_tiles/country_code_ios.h"
-#endif
-
-using net::URLFetcher;
-using variations::VariationsService;
-
-namespace ntp_tiles {
-
-namespace {
-
-const char kPopularSitesURLFormat[] =
-    "https://www.gstatic.com/chrome/ntp/suggested_sites_%s_%s.json";
-const char kPopularSitesDefaultCountryCode[] = "DEFAULT";
-const char kPopularSitesDefaultVersion[] = "5";
-const char kPopularSitesLocalFilename[] = "suggested_sites.json";
-const int kPopularSitesRedownloadIntervalHours = 24;
-
-const char kPopularSitesLastDownloadPref[] = "popular_sites_last_download";
-const char kPopularSitesURLPref[] = "popular_sites_url";
-
-GURL GetPopularSitesURL(const std::string& country,
-                        const std::string& version) {
-  return GURL(base::StringPrintf(kPopularSitesURLFormat, country.c_str(),
-                                 version.c_str()));
-}
-
-// Extract the country from the default search engine if the default search
-// engine is Google.
-std::string GetDefaultSearchEngineCountryCode(
-    const TemplateURLService* template_url_service) {
-  DCHECK(template_url_service);
-
-  base::CommandLine* cmd_line = base::CommandLine::ForCurrentProcess();
-  if (!cmd_line->HasSwitch(
-          ntp_tiles::switches::kEnableNTPSearchEngineCountryDetection))
-    return std::string();
-
-  const TemplateURL* default_provider =
-      template_url_service->GetDefaultSearchProvider();
-  // It's possible to not have a default provider in the case that the default
-  // search engine is defined by policy.
-  if (default_provider) {
-    bool is_google_search_engine =
-        default_provider->GetEngineType(
-            template_url_service->search_terms_data()) ==
-        SearchEngineType::SEARCH_ENGINE_GOOGLE;
-
-    if (is_google_search_engine) {
-      GURL search_url = default_provider->GenerateSearchURL(
-          template_url_service->search_terms_data());
-      return google_util::GetGoogleCountryCode(search_url);
-    }
-  }
-
-  return std::string();
-}
-
-std::string GetVariationCountry() {
-  return variations::GetVariationParamValue(kPopularSitesFieldTrialName,
-                                            "country");
-}
-
-std::string GetVariationVersion() {
-  return variations::GetVariationParamValue(kPopularSitesFieldTrialName,
-                                            "version");
-}
-
-// Must run on the blocking thread pool.
-bool WriteJsonToFile(const base::FilePath& local_path,
-                     const base::Value* json) {
-  std::string json_string;
-  return base::JSONWriter::Write(*json, &json_string) &&
-         base::ImportantFileWriter::WriteFileAtomically(local_path,
-                                                        json_string);
-}
-
-}  // namespace
-
-PopularSites::Site::Site(const base::string16& title,
-                         const GURL& url,
-                         const GURL& favicon_url,
-                         const GURL& large_icon_url,
-                         const GURL& thumbnail_url)
-    : title(title),
-      url(url),
-      favicon_url(favicon_url),
-      large_icon_url(large_icon_url),
-      thumbnail_url(thumbnail_url) {}
-
-PopularSites::Site::Site(const Site& other) = default;
-
-PopularSites::Site::~Site() {}
-
-PopularSitesImpl::PopularSitesImpl(
-    const scoped_refptr<base::SequencedWorkerPool>& blocking_pool,
-    PrefService* prefs,
-    const TemplateURLService* template_url_service,
-    VariationsService* variations_service,
-    net::URLRequestContextGetter* download_context,
-    const base::FilePath& directory,
-    ParseJSONCallback parse_json)
-    : blocking_runner_(blocking_pool->GetTaskRunnerWithShutdownBehavior(
-          base::SequencedWorkerPool::CONTINUE_ON_SHUTDOWN)),
-      prefs_(prefs),
-      template_url_service_(template_url_service),
-      variations_(variations_service),
-      download_context_(download_context),
-      local_path_(directory.empty()
-                      ? base::FilePath()
-                      : directory.AppendASCII(kPopularSitesLocalFilename)),
-      parse_json_(std::move(parse_json)),
-      is_fallback_(false),
-      weak_ptr_factory_(this) {}
-
-PopularSitesImpl::~PopularSitesImpl() {}
-
-void PopularSitesImpl::StartFetch(bool force_download,
-                                  const FinishedCallback& callback) {
-  DCHECK(!callback_);
-  callback_ = callback;
-
-  const base::Time last_download_time = base::Time::FromInternalValue(
-      prefs_->GetInt64(kPopularSitesLastDownloadPref));
-  const base::TimeDelta time_since_last_download =
-      base::Time::Now() - last_download_time;
-  const base::TimeDelta redownload_interval =
-      base::TimeDelta::FromHours(kPopularSitesRedownloadIntervalHours);
-  const bool download_time_is_future = base::Time::Now() < last_download_time;
-
-  pending_url_ = GetURLToFetch();
-  const bool url_changed =
-      pending_url_.spec() != prefs_->GetString(kPopularSitesURLPref);
-
-  // No valid path to save to. Immediately post failure.
-  if (local_path_.empty()) {
-    base::ThreadTaskRunnerHandle::Get()->PostTask(FROM_HERE,
-                                                  base::Bind(callback_, false));
-    return;
-  }
-
-  // Download forced, or we need to download a new file.
-  if (force_download || download_time_is_future ||
-      (time_since_last_download > redownload_interval) || url_changed) {
-    FetchPopularSites();
-    return;
-  }
-
-  std::unique_ptr<std::string> file_data(new std::string);
-  std::string* file_data_ptr = file_data.get();
-  base::PostTaskAndReplyWithResult(
-      blocking_runner_.get(), FROM_HERE,
-      base::Bind(&base::ReadFileToString, local_path_, file_data_ptr),
-      base::Bind(&PopularSitesImpl::OnReadFileDone,
-                 weak_ptr_factory_.GetWeakPtr(),
-                 base::Passed(std::move(file_data))));
-}
-
-const PopularSites::SitesVector& PopularSitesImpl::sites() const {
-  return sites_;
-}
-
-GURL PopularSitesImpl::GetLastURLFetched() const {
-  return GURL(prefs_->GetString(kPopularSitesURLPref));
-}
-
-const base::FilePath& PopularSitesImpl::local_path() const {
-  return local_path_;
-}
-
-GURL PopularSitesImpl::GetURLToFetch() {
-  const std::string country = GetCountryToFetch();
-  const std::string version = GetVersionToFetch();
-
-  const GURL override_url =
-      GURL(prefs_->GetString(ntp_tiles::prefs::kPopularSitesOverrideURL));
-  return override_url.is_valid() ? override_url
-                                 : GetPopularSitesURL(country, version);
-}
-
-// Determine the country code to use. In order of precedence:
-// - The explicit "override country" pref set by the user.
-// - The country code from the field trial config (variation parameter).
-// - The Google country code if Google is the default search engine (and the
-//   "--enable-ntp-search-engine-country-detection" switch is present).
-// - The country provided by the VariationsService.
-// - A default fallback.
-std::string PopularSitesImpl::GetCountryToFetch() {
-  std::string country_code =
-      prefs_->GetString(ntp_tiles::prefs::kPopularSitesOverrideCountry);
-
-  if (country_code.empty())
-    country_code = GetVariationCountry();
-
-  if (country_code.empty())
-    country_code = GetDefaultSearchEngineCountryCode(template_url_service_);
-
-  if (country_code.empty() && variations_)
-    country_code = variations_->GetStoredPermanentCountry();
-
-#if defined(OS_IOS)
-  if (country_code.empty())
-    country_code = GetDeviceCountryCode();
-#endif
-
-  if (country_code.empty())
-    country_code = kPopularSitesDefaultCountryCode;
-
-  return base::ToUpperASCII(country_code);
-}
-
-// Determine the version to use. In order of precedence:
-// - The explicit "override version" pref set by the user.
-// - The version from the field trial config (variation parameter).
-// - A default fallback.
-std::string PopularSitesImpl::GetVersionToFetch() {
-  std::string version =
-      prefs_->GetString(ntp_tiles::prefs::kPopularSitesOverrideVersion);
-
-  if (version.empty())
-    version = GetVariationVersion();
-
-  if (version.empty())
-    version = kPopularSitesDefaultVersion;
-
-  return version;
-}
-
-// static
-void PopularSitesImpl::RegisterProfilePrefs(
-    user_prefs::PrefRegistrySyncable* user_prefs) {
-  user_prefs->RegisterStringPref(ntp_tiles::prefs::kPopularSitesOverrideURL,
-                                 std::string());
-  user_prefs->RegisterStringPref(ntp_tiles::prefs::kPopularSitesOverrideCountry,
-                                 std::string());
-  user_prefs->RegisterStringPref(ntp_tiles::prefs::kPopularSitesOverrideVersion,
-                                 std::string());
-
-  user_prefs->RegisterInt64Pref(kPopularSitesLastDownloadPref, 0);
-  user_prefs->RegisterStringPref(kPopularSitesURLPref, std::string());
-}
-
-void PopularSitesImpl::OnReadFileDone(std::unique_ptr<std::string> data,
-                                      bool success) {
-  if (success) {
-    auto json = base::JSONReader::Read(*data, base::JSON_ALLOW_TRAILING_COMMAS);
-    if (json) {
-      ParseSiteList(std::move(json));
-    } else {
-      OnJsonParseFailed("previously-fetched JSON was no longer parseable");
-    }
-  } else {
-    // File didn't exist, or couldn't be read for some other reason.
-    FetchPopularSites();
-  }
-}
-
-void PopularSitesImpl::FetchPopularSites() {
-  fetcher_ = URLFetcher::Create(pending_url_, URLFetcher::GET, this);
-  data_use_measurement::DataUseUserData::AttachToFetcher(
-      fetcher_.get(), data_use_measurement::DataUseUserData::NTP_TILES);
-  fetcher_->SetRequestContext(download_context_);
-  fetcher_->SetLoadFlags(net::LOAD_DO_NOT_SEND_COOKIES |
-                         net::LOAD_DO_NOT_SAVE_COOKIES);
-  fetcher_->SetAutomaticallyRetryOnNetworkChanges(1);
-  fetcher_->Start();
-}
-
-void PopularSitesImpl::OnURLFetchComplete(const net::URLFetcher* source) {
-  DCHECK_EQ(fetcher_.get(), source);
-  std::unique_ptr<net::URLFetcher> free_fetcher = std::move(fetcher_);
-
-  std::string json_string;
-  if (!(source->GetStatus().is_success() &&
-        source->GetResponseCode() == net::HTTP_OK &&
-        source->GetResponseAsString(&json_string))) {
-    OnDownloadFailed();
-    return;
-  }
-
-  parse_json_.Run(json_string, base::Bind(&PopularSitesImpl::OnJsonParsed,
-                                          weak_ptr_factory_.GetWeakPtr()),
-                  base::Bind(&PopularSitesImpl::OnJsonParseFailed,
-                             weak_ptr_factory_.GetWeakPtr()));
-}
-
-void PopularSitesImpl::OnJsonParsed(std::unique_ptr<base::Value> json) {
-  const base::Value* json_ptr = json.get();
-  base::PostTaskAndReplyWithResult(
-      blocking_runner_.get(), FROM_HERE,
-      base::Bind(&WriteJsonToFile, local_path_, json_ptr),
-      base::Bind(&PopularSitesImpl::OnFileWriteDone,
-                 weak_ptr_factory_.GetWeakPtr(),
-                 base::Passed(std::move(json))));
-}
-
-void PopularSitesImpl::OnJsonParseFailed(const std::string& error_message) {
-  DLOG(WARNING) << "JSON parsing failed: " << error_message;
-  OnDownloadFailed();
-}
-
-void PopularSitesImpl::OnFileWriteDone(std::unique_ptr<base::Value> json,
-                                       bool success) {
-  if (success) {
-    prefs_->SetInt64(kPopularSitesLastDownloadPref,
-                     base::Time::Now().ToInternalValue());
-    prefs_->SetString(kPopularSitesURLPref, pending_url_.spec());
-    ParseSiteList(std::move(json));
-  } else {
-    DLOG(WARNING) << "Could not write file to "
-                  << local_path_.LossyDisplayName();
-    OnDownloadFailed();
-  }
-}
-
-void PopularSitesImpl::ParseSiteList(std::unique_ptr<base::Value> json) {
-  base::ListValue* list = nullptr;
-  if (!json || !json->GetAsList(&list)) {
-    DLOG(WARNING) << "JSON is not a list";
-    sites_.clear();
-    callback_.Run(false);
-    return;
-  }
-
-  SitesVector sites;
-  for (size_t i = 0; i < list->GetSize(); i++) {
-    base::DictionaryValue* item;
-    if (!list->GetDictionary(i, &item))
-      continue;
-    base::string16 title;
-    std::string url;
-    if (!item->GetString("title", &title) || !item->GetString("url", &url))
-      continue;
-    std::string favicon_url;
-    item->GetString("favicon_url", &favicon_url);
-    std::string thumbnail_url;
-    item->GetString("thumbnail_url", &thumbnail_url);
-    std::string large_icon_url;
-    item->GetString("large_icon_url", &large_icon_url);
-
-    sites.push_back(PopularSitesImpl::Site(title, GURL(url), GURL(favicon_url),
-                                           GURL(large_icon_url),
-                                           GURL(thumbnail_url)));
-  }
-
-  sites_.swap(sites);
-  callback_.Run(true);
-}
-
-void PopularSitesImpl::OnDownloadFailed() {
-  if (!is_fallback_) {
-    DLOG(WARNING) << "Download country site list failed";
-    is_fallback_ = true;
-    pending_url_ = GetPopularSitesURL(kPopularSitesDefaultCountryCode,
-                                      kPopularSitesDefaultVersion);
-    FetchPopularSites();
-  } else {
-    DLOG(WARNING) << "Download fallback site list failed";
-    callback_.Run(false);
-  }
-}
-
-}  // namespace ntp_tiles