// 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.

#if !defined(OS_ANDROID)

#include "chrome/browser/metrics/first_web_contents_profiler.h"

#include "base/metrics/histogram_macros.h"
#include "base/process/process_info.h"
#include "base/time/time.h"
#include "chrome/browser/ui/browser.h"
#include "chrome/browser/ui/browser_iterator.h"
#include "chrome/browser/ui/tabs/tab_strip_model.h"
#include "components/metrics/profiler/tracking_synchronizer.h"
#include "components/metrics/proto/profiler_event.pb.h"

scoped_ptr<FirstWebContentsProfiler>
FirstWebContentsProfiler::CreateProfilerForFirstWebContents(
    Delegate* delegate) {
  DCHECK(delegate);
  for (chrome::BrowserIterator iterator; !iterator.done(); iterator.Next()) {
    Browser* browser = *iterator;
    content::WebContents* web_contents =
        browser->tab_strip_model()->GetActiveWebContents();
    if (web_contents) {
      return scoped_ptr<FirstWebContentsProfiler>(
          new FirstWebContentsProfiler(web_contents, delegate));
    }
  }
  return nullptr;
}

FirstWebContentsProfiler::FirstWebContentsProfiler(
    content::WebContents* web_contents,
    Delegate* delegate)
    : content::WebContentsObserver(web_contents),
      collected_paint_metric_(false),
      collected_load_metric_(false),
      delegate_(delegate) {
  process_creation_time_ = base::CurrentProcessInfo::CreationTime();
}

void FirstWebContentsProfiler::DidFirstVisuallyNonEmptyPaint() {
  if (collected_paint_metric_)
    return;

  collected_paint_metric_ = true;
  if (!process_creation_time_.is_null()) {
    base::TimeDelta elapsed = base::Time::Now() - process_creation_time_;

    UMA_HISTOGRAM_LONG_TIMES_100("Startup.FirstWebContents.NonEmptyPaint",
                                 elapsed);
  }

  metrics::TrackingSynchronizer::OnProfilingPhaseCompleted(
      metrics::ProfilerEventProto::EVENT_FIRST_NONEMPTY_PAINT);

  if (IsFinishedCollectingMetrics())
    FinishedCollectingMetrics();
}

void FirstWebContentsProfiler::DocumentOnLoadCompletedInMainFrame() {
  if (collected_load_metric_)
    return;

  collected_load_metric_ = true;
  if (!process_creation_time_.is_null()) {
    base::TimeDelta elapsed = base::Time::Now() - process_creation_time_;

    UMA_HISTOGRAM_LONG_TIMES_100("Startup.FirstWebContents.MainFrameLoad",
                                 elapsed);
  }

  if (IsFinishedCollectingMetrics())
    FinishedCollectingMetrics();
}

void FirstWebContentsProfiler::WebContentsDestroyed() {
  FinishedCollectingMetrics();
}

bool FirstWebContentsProfiler::IsFinishedCollectingMetrics() {
  return collected_paint_metric_ && collected_load_metric_;
}

void FirstWebContentsProfiler::FinishedCollectingMetrics() {
  delegate_->ProfilerFinishedCollectingMetrics();
}

#endif  // !defined(OS_ANDROID)