[Offline Pages] Create a event/activity logger

components/offline_pages/offline_event_logger.cc

+// Copyright 2016 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 "base/strings/stringprintf.h"
+#include "base/time/time.h"
+#include "components/offline_pages/offline_event_logger.h"
+
+namespace offline_pages {
+
+OfflineEventLogger::OfflineEventLogger()
+    : activities_(kMaxLogCount), is_logging_(false) {}
+
+OfflineEventLogger::~OfflineEventLogger() {}
+
+void OfflineEventLogger::SetIsLogging(bool is_logging) {
+  is_logging_ = is_logging;
+}
+
+bool OfflineEventLogger::GetIsLogging() {
+  return is_logging_;
+}
+
+void OfflineEventLogger::Clear() {
+  activities_.clear();
+}
+
+void OfflineEventLogger::RecordActivity(const std::string& activity) {
+  if (!is_logging_) {
+    return;
+  }
+  if (activities_.size() == kMaxLogCount)
+    activities_.pop_back();
+
+  base::Time::Exploded current_time;
+  base::Time::Now().LocalExplode(&current_time);
+
+  std::string date_string = base::StringPrintf(
+      "%d %02d %02d %02d:%02d:%02d",
+      current_time.year,
+      current_time.month,
+      current_time.day_of_month,
+      current_time.hour,
+      current_time.minute,
+      current_time.second);
+
+  activities_.push_front(date_string + ": " + activity);
+}
+
+void OfflineEventLogger::GetLogs(std::vector<std::string>* records) {
+  DCHECK(records);
+  for (std::deque<std::string>::iterator it = activities_.begin();
+       it != activities_.end(); it++) {
+    if (!it->empty())
+      records->push_back(*it);
+  }
+}
+
+}  // namespace offline_pages