// Copyright (c) 2013 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/metrics/chrome_browser_main_extra_parts_metrics.h"

#include <string>

#include "base/bind.h"
#include "base/command_line.h"
#include "base/cpu.h"
#include "base/metrics/histogram.h"
#include "base/metrics/sparse_histogram.h"
#include "base/sys_info.h"
#include "base/threading/sequenced_worker_pool.h"
#include "base/time/time.h"
#include "chrome/browser/about_flags.h"
#include "chrome/browser/browser_process.h"
#include "chrome/browser/chrome_browser_main.h"
#include "chrome/browser/pref_service_flags_storage.h"
#include "chrome/browser/shell_integration.h"
#include "content/public/browser/browser_thread.h"
#include "ui/base/touch/touch_device.h"
#include "ui/base/ui_base_switches.h"
#include "ui/events/event_switches.h"

#if defined(OS_LINUX) && !defined(OS_CHROMEOS)
#include <gnu/libc-version.h>

#include "base/version.h"
#endif

namespace {

enum UMALinuxGlibcVersion {
  UMA_LINUX_GLIBC_NOT_PARSEABLE,
  UMA_LINUX_GLIBC_UNKNOWN,
  UMA_LINUX_GLIBC_2_11,
  UMA_LINUX_GLIBC_2_19 = UMA_LINUX_GLIBC_2_11 + 8,
  // NOTE: Add new version above this line and update the enum list in
  // tools/histograms/histograms.xml accordingly.
  UMA_LINUX_GLIBC_VERSION_COUNT
};

enum UMATouchEventsState {
  UMA_TOUCH_EVENTS_ENABLED,
  UMA_TOUCH_EVENTS_AUTO_ENABLED,
  UMA_TOUCH_EVENTS_AUTO_DISABLED,
  UMA_TOUCH_EVENTS_DISABLED,
  // NOTE: Add states only immediately above this line. Make sure to
  // update the enum list in tools/histograms/histograms.xml accordingly.
  UMA_TOUCH_EVENTS_STATE_COUNT
};

void RecordMicroArchitectureStats() {
#if defined(ARCH_CPU_X86_FAMILY)
  base::CPU cpu;
  base::CPU::IntelMicroArchitecture arch = cpu.GetIntelMicroArchitecture();
  UMA_HISTOGRAM_ENUMERATION("Platform.IntelMaxMicroArchitecture", arch,
                            base::CPU::MAX_INTEL_MICRO_ARCHITECTURE);
#endif  // defined(ARCH_CPU_X86_FAMILY)
  UMA_HISTOGRAM_SPARSE_SLOWLY("Platform.LogicalCpuCount",
                              base::SysInfo::NumberOfProcessors());
}

void RecordDefaultBrowserUMAStat() {
  // Record whether Chrome is the default browser or not.
  ShellIntegration::DefaultWebClientState default_state =
      ShellIntegration::GetDefaultBrowser();
  UMA_HISTOGRAM_ENUMERATION("DefaultBrowser.State", default_state,
                            ShellIntegration::NUM_DEFAULT_STATES);
}

void RecordLinuxGlibcVersion() {
#if defined(OS_LINUX) && !defined(OS_CHROMEOS)
  Version version(gnu_get_libc_version());

  UMALinuxGlibcVersion glibc_version_result = UMA_LINUX_GLIBC_NOT_PARSEABLE;
  if (version.IsValid() && version.components().size() == 2) {
    glibc_version_result = UMA_LINUX_GLIBC_UNKNOWN;
    int glibc_major_version = version.components()[0];
    int glibc_minor_version = version.components()[1];
    if (glibc_major_version == 2) {
      // A constant to translate glibc 2.x minor versions to their
      // equivalent UMALinuxGlibcVersion values.
      const int kGlibcMinorVersionTranslationOffset = 11 - UMA_LINUX_GLIBC_2_11;
      int translated_glibc_minor_version =
          glibc_minor_version - kGlibcMinorVersionTranslationOffset;
      if (translated_glibc_minor_version >= UMA_LINUX_GLIBC_2_11 &&
          translated_glibc_minor_version <= UMA_LINUX_GLIBC_2_19) {
        glibc_version_result =
            static_cast<UMALinuxGlibcVersion>(translated_glibc_minor_version);
      }
    }
  }
  UMA_HISTOGRAM_ENUMERATION("Linux.GlibcVersion", glibc_version_result,
                            UMA_LINUX_GLIBC_VERSION_COUNT);
#endif
}

void RecordTouchEventState() {
  const CommandLine& command_line = *CommandLine::ForCurrentProcess();
  const std::string touch_enabled_switch =
      command_line.HasSwitch(switches::kTouchEvents) ?
      command_line.GetSwitchValueASCII(switches::kTouchEvents) :
      switches::kTouchEventsAuto;

  UMATouchEventsState state;
  if (touch_enabled_switch.empty() ||
      touch_enabled_switch == switches::kTouchEventsEnabled) {
    state = UMA_TOUCH_EVENTS_ENABLED;
  } else if (touch_enabled_switch == switches::kTouchEventsAuto) {
    state = ui::IsTouchDevicePresent() ?
        UMA_TOUCH_EVENTS_AUTO_ENABLED : UMA_TOUCH_EVENTS_AUTO_DISABLED;
  } else if (touch_enabled_switch == switches::kTouchEventsDisabled) {
    state = UMA_TOUCH_EVENTS_DISABLED;
  } else {
    NOTREACHED();
    return;
  }

  UMA_HISTOGRAM_ENUMERATION("Touchscreen.TouchEventsEnabled", state,
                            UMA_TOUCH_EVENTS_STATE_COUNT);
}

}  // namespace

ChromeBrowserMainExtraPartsMetrics::ChromeBrowserMainExtraPartsMetrics() {
}

ChromeBrowserMainExtraPartsMetrics::~ChromeBrowserMainExtraPartsMetrics() {
}

void ChromeBrowserMainExtraPartsMetrics::PreProfileInit() {
  RecordMicroArchitectureStats();
}

void ChromeBrowserMainExtraPartsMetrics::PreBrowserStart() {
  about_flags::PrefServiceFlagsStorage flags_storage_(
      g_browser_process->local_state());
  about_flags::RecordUMAStatistics(&flags_storage_);

  // Querying the default browser state can be slow, do it in the background.
  content::BrowserThread::GetBlockingPool()->PostDelayedTask(
        FROM_HERE,
        base::Bind(&RecordDefaultBrowserUMAStat),
        base::TimeDelta::FromSeconds(45));
}

void ChromeBrowserMainExtraPartsMetrics::PostBrowserStart() {
  RecordLinuxGlibcVersion();
  RecordTouchEventState();
}

namespace chrome {

void AddMetricsExtraParts(ChromeBrowserMainParts* main_parts) {
  main_parts->AddParts(new ChromeBrowserMainExtraPartsMetrics());
}

}  // namespace chrome