// 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.

#import "ios/chrome/app/memory_monitor.h"

#include <dispatch/dispatch.h>
#import <Foundation/NSPathUtilities.h>

#include "base/bind.h"
#include "base/files/file_path.h"
#include "base/files/file_util.h"
#include "base/location.h"
#include "base/logging.h"
#import "base/mac/foundation_util.h"
#include "base/strings/sys_string_conversions.h"
#include "base/system/sys_info.h"
#include "base/task/post_task.h"
#include "base/threading/scoped_blocking_call.h"
#import "ios/chrome/browser/crash_report/breakpad_helper.h"
#import "ios/chrome/browser/metrics/previous_session_info.h"

#if !defined(__has_feature) || !__has_feature(objc_arc)
#error "This file requires ARC support."
#endif

namespace {
// Delay between each invocations of |UpdateMemoryValues|.
const int64_t kMemoryMonitorDelayInSeconds = 30;

// Checks the values of free RAM and free disk space and updates breakpad with
// these values. Also updates available free disk space for PreviousSessionInfo.
void UpdateMemoryValues() {
  base::ScopedBlockingCall scoped_blocking_call(FROM_HERE,
                                                base::BlockingType::WILL_BLOCK);
  const int free_memory =
      static_cast<int>(base::SysInfo::AmountOfAvailablePhysicalMemory() / 1024);
  breakpad_helper::SetCurrentFreeMemoryInKB(free_memory);

  NSURL* fileURL = [[NSURL alloc] initFileURLWithPath:@"/"];
  NSDictionary* results = [fileURL resourceValuesForKeys:@[
    NSURLVolumeAvailableCapacityForImportantUsageKey
  ]
                                                   error:nil];
  int free_disk_space_kilobytes = -1;
  if (results) {
    NSNumber* available_bytes =
        results[NSURLVolumeAvailableCapacityForImportantUsageKey];
    free_disk_space_kilobytes = [available_bytes integerValue] / 1024;
  }
  breakpad_helper::SetCurrentFreeDiskInKB(free_disk_space_kilobytes);
  [[PreviousSessionInfo sharedInstance]
      updateAvailableDeviceStorage:(NSInteger)free_disk_space_kilobytes];
}

// Invokes |UpdateMemoryValues| and schedules itself to be called after
// |kMemoryMonitorDelayInSeconds|.
void AsynchronousFreeMemoryMonitor() {
  UpdateMemoryValues();
  base::PostDelayedTaskWithTraits(
      FROM_HERE, {base::MayBlock(), base::TaskPriority::BEST_EFFORT},
      base::BindOnce(&AsynchronousFreeMemoryMonitor),
      base::TimeDelta::FromSeconds(kMemoryMonitorDelayInSeconds));
}
}  // namespace

void StartFreeMemoryMonitor() {
  base::PostTaskWithTraits(FROM_HERE,
                           {base::MayBlock(), base::TaskPriority::BEST_EFFORT},
                           base::BindOnce(&AsynchronousFreeMemoryMonitor));
}