/* -*- Mode: C++; tab-width: 20; indent-tabs-mode: nil; c-basic-offset: 2 -*-
 * This Source Code Form is subject to the terms of the Mozilla Public
 * License, v. 2.0. If a copy of the MPL was not distributed with this
 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */

// This file makes some assumptions about the versions of OS X.
// We are assuming that the minor and bugfix versions are less than 16.
// There are MOZ_ASSERTs for that.

// The formula for the version integer based on OS X version 10.minor.bugfix is
// 0x1000 + (minor << 4) + bugifix.  See AssembleVersion() below for major > 10.
// Major version < 10 is not allowed.

#define MAC_OS_X_VERSION_MASK 0x0000FFFF
#define MAC_OS_X_VERSION_10_0_HEX 0x00001000
#define MAC_OS_X_VERSION_10_7_HEX 0x00001070
#define MAC_OS_X_VERSION_10_8_HEX 0x00001080
#define MAC_OS_X_VERSION_10_9_HEX 0x00001090
#define MAC_OS_X_VERSION_10_10_HEX 0x000010A0
#define MAC_OS_X_VERSION_10_11_HEX 0x000010B0
#define MAC_OS_X_VERSION_10_12_HEX 0x000010C0
#define MAC_OS_X_VERSION_10_13_HEX 0x000010D0
#define MAC_OS_X_VERSION_10_14_HEX 0x000010E0
#define MAC_OS_X_VERSION_10_15_HEX 0x000010F0

#include "nsCocoaFeatures.h"
#include "nsCocoaUtils.h"
#include "nsDebug.h"
#include "nsObjCExceptions.h"

#import <Cocoa/Cocoa.h>

int32_t nsCocoaFeatures::mOSXVersion = 0;

// This should not be called with unchecked aMajor, which should be >= 10.
inline int32_t AssembleVersion(int32_t aMajor, int32_t aMinor, int32_t aBugFix) {
  MOZ_ASSERT(aMajor >= 10);
  return MAC_OS_X_VERSION_10_0_HEX + (aMajor - 10) * 0x100 + (aMinor << 4) + aBugFix;
}

int32_t nsCocoaFeatures::ExtractMajorVersion(int32_t aVersion) {
  MOZ_ASSERT((aVersion & MAC_OS_X_VERSION_MASK) == aVersion);
  return ((aVersion & 0xFF00) - 0x1000) / 0x100 + 10;
}

int32_t nsCocoaFeatures::ExtractMinorVersion(int32_t aVersion) {
  MOZ_ASSERT((aVersion & MAC_OS_X_VERSION_MASK) == aVersion);
  return (aVersion & 0xF0) >> 4;
}

int32_t nsCocoaFeatures::ExtractBugFixVersion(int32_t aVersion) {
  MOZ_ASSERT((aVersion & MAC_OS_X_VERSION_MASK) == aVersion);
  return aVersion & 0x0F;
}

static int intAtStringIndex(NSArray* array, int index) {
  return [(NSString*)[array objectAtIndex:index] integerValue];
}

void nsCocoaFeatures::GetSystemVersion(int& major, int& minor, int& bugfix) {
  major = minor = bugfix = 0;

  NSString* versionString = [[NSDictionary
      dictionaryWithContentsOfFile:@"/System/Library/CoreServices/SystemVersion.plist"]
      objectForKey:@"ProductVersion"];
  NSArray* versions = [versionString componentsSeparatedByString:@"."];
  NSUInteger count = [versions count];
  if (count > 0) {
    major = intAtStringIndex(versions, 0);
    if (count > 1) {
      minor = intAtStringIndex(versions, 1);
      if (count > 2) {
        bugfix = intAtStringIndex(versions, 2);
      }
    }
  }
}

int32_t nsCocoaFeatures::GetVersion(int32_t aMajor, int32_t aMinor, int32_t aBugFix) {
  int32_t osxVersion;
  if (aMajor < 10) {
    aMajor = 10;
    NS_ERROR("Couldn't determine OS X version, assuming 10.7");
    osxVersion = MAC_OS_X_VERSION_10_7_HEX;
  } else if (aMinor < 7) {
    aMinor = 7;
    NS_ERROR("OS X version too old, assuming 10.7");
    osxVersion = MAC_OS_X_VERSION_10_7_HEX;
  } else {
    MOZ_ASSERT(aMajor == 10);  // For now, even though we're ready...
    MOZ_ASSERT(aMinor < 16);
    MOZ_ASSERT(aBugFix >= 0);
    MOZ_ASSERT(aBugFix < 16);
    osxVersion = AssembleVersion(aMajor, aMinor, aBugFix);
  }
  MOZ_ASSERT(aMajor == ExtractMajorVersion(osxVersion));
  MOZ_ASSERT(aMinor == ExtractMinorVersion(osxVersion));
  MOZ_ASSERT(aBugFix == ExtractBugFixVersion(osxVersion));
  return osxVersion;
}

/*static*/ void nsCocoaFeatures::InitializeVersionNumbers() {
  NS_OBJC_BEGIN_TRY_ABORT_BLOCK;

  // Provide an autorelease pool to avoid leaking Cocoa objects,
  // as this gets called before the main autorelease pool is in place.
  nsAutoreleasePool localPool;

  int major, minor, bugfix;
  GetSystemVersion(major, minor, bugfix);
  mOSXVersion = GetVersion(major, minor, bugfix);

  NS_OBJC_END_TRY_ABORT_BLOCK;
}

/* static */ int32_t nsCocoaFeatures::OSXVersion() {
  // Don't let this be called while we're first setting the value...
  MOZ_ASSERT((mOSXVersion & MAC_OS_X_VERSION_MASK) >= 0);
  if (!mOSXVersion) {
    mOSXVersion = -1;
    InitializeVersionNumbers();
  }
  return mOSXVersion;
}

/* static */ int32_t nsCocoaFeatures::OSXVersionMajor() {
  MOZ_ASSERT((OSXVersion() & MAC_OS_X_VERSION_10_0_HEX) == MAC_OS_X_VERSION_10_0_HEX);
  return 10;
}

/* static */ int32_t nsCocoaFeatures::OSXVersionMinor() {
  return ExtractMinorVersion(OSXVersion());
}

/* static */ int32_t nsCocoaFeatures::OSXVersionBugFix() {
  return ExtractBugFixVersion(OSXVersion());
}

/* static */ bool nsCocoaFeatures::OnYosemiteOrLater() {
  return (OSXVersion() >= MAC_OS_X_VERSION_10_10_HEX);
}

/* static */ bool nsCocoaFeatures::OnElCapitanOrLater() {
  return (OSXVersion() >= MAC_OS_X_VERSION_10_11_HEX);
}

/* static */ bool nsCocoaFeatures::OnSierraExactly() {
  return (OSXVersion() >= MAC_OS_X_VERSION_10_12_HEX) &&
         (OSXVersion() < MAC_OS_X_VERSION_10_13_HEX);
}

/* Version of OnSierraExactly as global function callable from cairo & skia */
bool Gecko_OnSierraExactly() { return nsCocoaFeatures::OnSierraExactly(); }

/* static */ bool nsCocoaFeatures::OnSierraOrLater() {
  return (OSXVersion() >= MAC_OS_X_VERSION_10_12_HEX);
}

/* static */ bool nsCocoaFeatures::OnHighSierraOrLater() {
  return (OSXVersion() >= MAC_OS_X_VERSION_10_13_HEX);
}

bool Gecko_OnHighSierraOrLater() { return nsCocoaFeatures::OnHighSierraOrLater(); }

/* static */ bool nsCocoaFeatures::OnMojaveOrLater() {
  return (OSXVersion() >= MAC_OS_X_VERSION_10_14_HEX);
}

/* static */ bool nsCocoaFeatures::OnCatalinaOrLater() {
  return (OSXVersion() >= MAC_OS_X_VERSION_10_15_HEX);
}

/* static */ bool nsCocoaFeatures::IsAtLeastVersion(int32_t aMajor, int32_t aMinor,
                                                    int32_t aBugFix) {
  return OSXVersion() >= GetVersion(aMajor, aMinor, aBugFix);
}
