// Copyright (c) 2012 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.

#ifndef BASE_WIN_WINDOWS_VERSION_H_
#define BASE_WIN_WINDOWS_VERSION_H_

#include <stddef.h>

#include <string>

#include "base/base_export.h"
#include "base/gtest_prod_util.h"
#include "base/macros.h"
#include "base/version.h"

using HANDLE = void*;
struct _OSVERSIONINFOEXW;
struct _SYSTEM_INFO;

namespace base {
namespace test {
class ScopedOSInfoOverride;
}  // namespace test
}  // namespace base

namespace base {
namespace win {

// The running version of Windows.  This is declared outside OSInfo for
// syntactic sugar reasons; see the declaration of GetVersion() below.
// NOTE: Keep these in order so callers can do things like
// "if (base::win::GetVersion() >= base::win::Version::VISTA) ...".
//
// This enum is used in metrics histograms, so they shouldn't be reordered or
// removed. New values can be added before Version::WIN_LAST.
enum class Version {
  PRE_XP = 0,  // Not supported.
  XP = 1,
  SERVER_2003 = 2,  // Also includes XP Pro x64 and Server 2003 R2.
  VISTA = 3,        // Also includes Windows Server 2008.
  WIN7 = 4,         // Also includes Windows Server 2008 R2.
  WIN8 = 5,         // Also includes Windows Server 2012.
  WIN8_1 = 6,       // Also includes Windows Server 2012 R2.
  WIN10 = 7,        // Threshold 1: Version 1507, Build 10240.
  WIN10_TH2 = 8,    // Threshold 2: Version 1511, Build 10586.
  WIN10_RS1 = 9,    // Redstone 1: Version 1607, Build 14393.
  WIN10_RS2 = 10,   // Redstone 2: Version 1703, Build 15063.
  WIN10_RS3 = 11,   // Redstone 3: Version 1709, Build 16299.
  WIN10_RS4 = 12,   // Redstone 4: Version 1803, Build 17134.
  WIN10_RS5 = 13,   // Redstone 5: Version 1809, Build 17763.
  WIN10_19H1 = 14,  // 19H1: Version 1903, Build 18362.
  WIN10_20H1 = 15,  // 20H1: Version 2004, Build 19041.
  // On edit, update tools\metrics\histograms\enums.xml "WindowsVersion" and
  // "GpuBlacklistFeatureTestResultsWindows2".
  WIN_LAST,  // Indicates error condition.
};

// A rough bucketing of the available types of versions of Windows. This is used
// to distinguish enterprise enabled versions from home versions and potentially
// server versions. Keep these values in the same order, since they are used as
// is for metrics histogram ids.
enum VersionType {
  SUITE_HOME = 0,
  SUITE_PROFESSIONAL,
  SUITE_SERVER,
  SUITE_ENTERPRISE,
  SUITE_EDUCATION,
  SUITE_LAST,
};

// A singleton that can be used to query various pieces of information about the
// OS and process state. Note that this doesn't use the base Singleton class, so
// it can be used without an AtExitManager.
class BASE_EXPORT OSInfo {
 public:
  struct VersionNumber {
    int major;
    int minor;
    int build;
    int patch;
  };

  struct ServicePack {
    int major;
    int minor;
  };

  // The processor architecture this copy of Windows natively uses.  For
  // example, given an x64-capable processor, we have three possibilities:
  //   32-bit Chrome running on 32-bit Windows:           X86_ARCHITECTURE
  //   32-bit Chrome running on 64-bit Windows via WOW64: X64_ARCHITECTURE
  //   64-bit Chrome running on 64-bit Windows:           X64_ARCHITECTURE
  enum WindowsArchitecture {
    X86_ARCHITECTURE,
    X64_ARCHITECTURE,
    IA64_ARCHITECTURE,
    ARM64_ARCHITECTURE,
    OTHER_ARCHITECTURE,
  };

  // Whether a process is running under WOW64 (the wrapper that allows 32-bit
  // processes to run on 64-bit versions of Windows).  This will return
  // WOW64_DISABLED for both "32-bit Chrome on 32-bit Windows" and "64-bit
  // Chrome on 64-bit Windows".  WOW64_UNKNOWN means "an error occurred", e.g.
  // the process does not have sufficient access rights to determine this.
  enum WOW64Status {
    WOW64_DISABLED,
    WOW64_ENABLED,
    WOW64_UNKNOWN,
  };

  static OSInfo* GetInstance();

  // Separate from the rest of OSInfo so it can be used during early process
  // initialization.
  static WindowsArchitecture GetArchitecture();

  // Like wow64_status(), but for the supplied handle instead of the current
  // process.  This doesn't touch member state, so you can bypass the singleton.
  static WOW64Status GetWOW64StatusForProcess(HANDLE process_handle);

  const Version& version() const { return version_; }
  Version Kernel32Version() const;
  base::Version Kernel32BaseVersion() const;
  // The next two functions return arrays of values, [major, minor(, build)].
  const VersionNumber& version_number() const { return version_number_; }
  const VersionType& version_type() const { return version_type_; }
  const ServicePack& service_pack() const { return service_pack_; }
  const std::string& service_pack_str() const { return service_pack_str_; }
  const int& processors() const { return processors_; }
  const size_t& allocation_granularity() const {
    return allocation_granularity_;
  }
  const WOW64Status& wow64_status() const { return wow64_status_; }
  std::string processor_model_name();
  const std::string& release_id() const { return release_id_; }

 private:
  friend class base::test::ScopedOSInfoOverride;
  FRIEND_TEST_ALL_PREFIXES(OSInfo, MajorMinorBuildToVersion);
  static OSInfo** GetInstanceStorage();

  OSInfo(const _OSVERSIONINFOEXW& version_info,
         const _SYSTEM_INFO& system_info,
         int os_type);
  ~OSInfo();

  // Returns a Version value for a given OS version tuple.
  static Version MajorMinorBuildToVersion(int major, int minor, int build);

  Version version_;
  VersionNumber version_number_;
  VersionType version_type_;
  ServicePack service_pack_;

  // Represents the version of the OS associated to a release of
  // Windows 10. Each version may have different releases (such as patch
  // updates). This is the identifier of the release.
  // Example:
  //    Windows 10 Version 1809 (OS build 17763) has multiple releases
  //    (i.e. build 17763.1, build 17763.195, build 17763.379, ...).
  // See https://docs.microsoft.com/en-us/windows/windows-10/release-information
  // for more information.
  std::string release_id_;

  // A string, such as "Service Pack 3", that indicates the latest Service Pack
  // installed on the system. If no Service Pack has been installed, the string
  // is empty.
  std::string service_pack_str_;
  int processors_;
  size_t allocation_granularity_;
  WOW64Status wow64_status_;
  std::string processor_model_name_;

  DISALLOW_COPY_AND_ASSIGN(OSInfo);
};

// Because this is by far the most commonly-requested value from the above
// singleton, we add a global-scope accessor here as syntactic sugar.
BASE_EXPORT Version GetVersion();

}  // namespace win
}  // namespace base

#endif  // BASE_WIN_WINDOWS_VERSION_H_