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/* -*- 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/. */

#include "gfxPlatformMac.h"

#include "gfxQuartzSurface.h"
#include "mozilla/gfx/2D.h"
#include "mozilla/gfx/MacIOSurface.h"

#include "gfxMacPlatformFontList.h"
#include "gfxMacFont.h"
#include "gfxCoreTextShaper.h"
#include "gfxTextRun.h"
#include "gfxUserFontSet.h"

#include "nsTArray.h"
#include "mozilla/Preferences.h"
#include "mozilla/VsyncDispatcher.h"
#include "nsCocoaFeatures.h"
#include "nsUnicodeProperties.h"
#include "qcms.h"
#include "gfx2DGlue.h"

#include <dlfcn.h>
#include <CoreVideo/CoreVideo.h>

#include "mozilla/layers/CompositorBridgeParent.h"
#include "VsyncSource.h"

using namespace mozilla;
using namespace mozilla::gfx;
using namespace mozilla::unicode;

using mozilla::dom::SystemFontListEntry;

// cribbed from CTFontManager.h
enum { kAutoActivationDisabled = 1 };
typedef uint32_t AutoActivationSetting;

// bug 567552 - disable auto-activation of fonts

static void DisableFontActivation() {
  // get the main bundle identifier
  CFBundleRef mainBundle = ::CFBundleGetMainBundle();
  CFStringRef mainBundleID = nullptr;

  if (mainBundle) {
    mainBundleID = ::CFBundleGetIdentifier(mainBundle);
  }

  // bug 969388 and bug 922590 - mainBundlID as null is sometimes problematic
  if (!mainBundleID) {
    NS_WARNING("missing bundle ID, packaging set up incorrectly");
    return;
  }

  // if possible, fetch CTFontManagerSetAutoActivationSetting
  void (*CTFontManagerSetAutoActivationSettingPtr)(CFStringRef,
                                                   AutoActivationSetting);
  CTFontManagerSetAutoActivationSettingPtr =
      (void (*)(CFStringRef, AutoActivationSetting))dlsym(
          RTLD_DEFAULT, "CTFontManagerSetAutoActivationSetting");

  // bug 567552 - disable auto-activation of fonts
  if (CTFontManagerSetAutoActivationSettingPtr) {
    CTFontManagerSetAutoActivationSettingPtr(mainBundleID,
                                             kAutoActivationDisabled);
  }
}

gfxPlatformMac::gfxPlatformMac() {
  DisableFontActivation();
  mFontAntiAliasingThreshold = ReadAntiAliasingThreshold();

  InitBackendPrefs(GetBackendPrefs());

  MacIOSurfaceLib::LoadLibrary();

  if (nsCocoaFeatures::OnHighSierraOrLater()) {
    mHasNativeColrFontSupport = true;
  }
}

gfxPlatformMac::~gfxPlatformMac() { gfxCoreTextShaper::Shutdown(); }

BackendPrefsData gfxPlatformMac::GetBackendPrefs() const {
  BackendPrefsData data;

  data.mCanvasBitmask = BackendTypeBit(BackendType::SKIA);
  data.mContentBitmask = BackendTypeBit(BackendType::SKIA);
  data.mCanvasDefault = BackendType::SKIA;
  data.mContentDefault = BackendType::SKIA;

  return data;
}

bool gfxPlatformMac::UsesTiling() const {
  // The non-tiling ContentClient requires CrossProcessSemaphore which
  // isn't implemented for OSX.
  return true;
}

bool gfxPlatformMac::ContentUsesTiling() const { return UsesTiling(); }

gfxPlatformFontList* gfxPlatformMac::CreatePlatformFontList() {
  gfxPlatformFontList* list = new gfxMacPlatformFontList();
  if (NS_SUCCEEDED(list->InitFontList())) {
    return list;
  }
  gfxPlatformFontList::Shutdown();
  return nullptr;
}

void gfxPlatformMac::ReadSystemFontList(
    InfallibleTArray<SystemFontListEntry>* aFontList) {
  gfxMacPlatformFontList::PlatformFontList()->ReadSystemFontList(aFontList);
}

already_AddRefed<gfxASurface> gfxPlatformMac::CreateOffscreenSurface(
    const IntSize& aSize, gfxImageFormat aFormat) {
  if (!Factory::AllowedSurfaceSize(aSize)) {
    return nullptr;
  }

  RefPtr<gfxASurface> newSurface = new gfxQuartzSurface(aSize, aFormat);
  return newSurface.forget();
}

gfxFontGroup* gfxPlatformMac::CreateFontGroup(
    const FontFamilyList& aFontFamilyList, const gfxFontStyle* aStyle,
    gfxTextPerfMetrics* aTextPerf, gfxUserFontSet* aUserFontSet,
    gfxFloat aDevToCssSize) {
  return new gfxFontGroup(aFontFamilyList, aStyle, aTextPerf, aUserFontSet,
                          aDevToCssSize);
}

bool gfxPlatformMac::IsFontFormatSupported(uint32_t aFormatFlags) {
  if (gfxPlatform::IsFontFormatSupported(aFormatFlags)) {
    return true;
  }

  // If the generic method rejected the format hint, then check for any
  // platform-specific format we know about.
  if (aFormatFlags & gfxUserFontSet::FLAG_FORMAT_TRUETYPE_AAT) {
    return true;
  }

  return false;
}

static const char kFontArialUnicodeMS[] = "Arial Unicode MS";
static const char kFontAppleBraille[] = "Apple Braille";
static const char kFontAppleColorEmoji[] = "Apple Color Emoji";
static const char kFontAppleSymbols[] = "Apple Symbols";
static const char kFontDevanagariSangamMN[] = "Devanagari Sangam MN";
static const char kFontEuphemiaUCAS[] = "Euphemia UCAS";
static const char kFontGeneva[] = "Geneva";
static const char kFontGeezaPro[] = "Geeza Pro";
static const char kFontGujaratiSangamMN[] = "Gujarati Sangam MN";
static const char kFontGurmukhiMN[] = "Gurmukhi MN";
static const char kFontHiraginoKakuGothic[] = "Hiragino Kaku Gothic ProN";
static const char kFontHiraginoSansGB[] = "Hiragino Sans GB";
static const char kFontKefa[] = "Kefa";
static const char kFontKhmerMN[] = "Khmer MN";
static const char kFontLaoMN[] = "Lao MN";
static const char kFontLucidaGrande[] = "Lucida Grande";
static const char kFontMenlo[] = "Menlo";
static const char kFontMicrosoftTaiLe[] = "Microsoft Tai Le";
static const char kFontMingLiUExtB[] = "MingLiU-ExtB";
static const char kFontMyanmarMN[] = "Myanmar MN";
static const char kFontPlantagenetCherokee[] = "Plantagenet Cherokee";
static const char kFontSimSunExtB[] = "SimSun-ExtB";
static const char kFontSongtiSC[] = "Songti SC";
static const char kFontSTHeiti[] = "STHeiti";
static const char kFontSTIXGeneral[] = "STIXGeneral";
static const char kFontTamilMN[] = "Tamil MN";

void gfxPlatformMac::GetCommonFallbackFonts(uint32_t aCh, uint32_t aNextCh,
                                            Script aRunScript,
                                            nsTArray<const char*>& aFontList) {
  EmojiPresentation emoji = GetEmojiPresentation(aCh);
  if (emoji != EmojiPresentation::TextOnly) {
    if (aNextCh == kVariationSelector16 ||
        (aNextCh != kVariationSelector15 &&
         emoji == EmojiPresentation::EmojiDefault)) {
      // if char is followed by VS16, try for a color emoji glyph
      aFontList.AppendElement(kFontAppleColorEmoji);
    }
  }

  aFontList.AppendElement(kFontLucidaGrande);

  if (!IS_IN_BMP(aCh)) {
    uint32_t p = aCh >> 16;
    if (p == 1) {
      aFontList.AppendElement(kFontAppleSymbols);
      aFontList.AppendElement(kFontSTIXGeneral);
      aFontList.AppendElement(kFontGeneva);
    } else if (p == 2) {
      // OSX installations with MS Office may have these fonts
      aFontList.AppendElement(kFontMingLiUExtB);
      aFontList.AppendElement(kFontSimSunExtB);
    }
  } else {
    uint32_t b = (aCh >> 8) & 0xff;

    switch (b) {
      case 0x03:
      case 0x05:
        aFontList.AppendElement(kFontGeneva);
        break;
      case 0x07:
        aFontList.AppendElement(kFontGeezaPro);
        break;
      case 0x09:
        aFontList.AppendElement(kFontDevanagariSangamMN);
        break;
      case 0x0a:
        aFontList.AppendElement(kFontGurmukhiMN);
        aFontList.AppendElement(kFontGujaratiSangamMN);
        break;
      case 0x0b:
        aFontList.AppendElement(kFontTamilMN);
        break;
      case 0x0e:
        aFontList.AppendElement(kFontLaoMN);
        break;
      case 0x0f:
        aFontList.AppendElement(kFontSongtiSC);
        break;
      case 0x10:
        aFontList.AppendElement(kFontMenlo);
        aFontList.AppendElement(kFontMyanmarMN);
        break;
      case 0x13:  // Cherokee
        aFontList.AppendElement(kFontPlantagenetCherokee);
        aFontList.AppendElement(kFontKefa);
        break;
      case 0x14:  // Unified Canadian Aboriginal Syllabics
      case 0x15:
      case 0x16:
        aFontList.AppendElement(kFontEuphemiaUCAS);
        aFontList.AppendElement(kFontGeneva);
        break;
      case 0x18:  // Mongolian, UCAS
        aFontList.AppendElement(kFontSTHeiti);
        aFontList.AppendElement(kFontEuphemiaUCAS);
        break;
      case 0x19:  // Khmer
        aFontList.AppendElement(kFontKhmerMN);
        aFontList.AppendElement(kFontMicrosoftTaiLe);
        break;
      case 0x1d:
      case 0x1e:
        aFontList.AppendElement(kFontGeneva);
        break;
      case 0x20:  // Symbol ranges
      case 0x21:
      case 0x22:
      case 0x23:
      case 0x24:
      case 0x25:
      case 0x26:
      case 0x27:
      case 0x29:
      case 0x2a:
      case 0x2b:
      case 0x2e:
        aFontList.AppendElement(kFontHiraginoKakuGothic);
        aFontList.AppendElement(kFontAppleSymbols);
        aFontList.AppendElement(kFontMenlo);
        aFontList.AppendElement(kFontSTIXGeneral);
        aFontList.AppendElement(kFontGeneva);
        aFontList.AppendElement(kFontAppleColorEmoji);
        break;
      case 0x2c:
        aFontList.AppendElement(kFontGeneva);
        break;
      case 0x2d:
        aFontList.AppendElement(kFontKefa);
        aFontList.AppendElement(kFontGeneva);
        break;
      case 0x28:  // Braille
        aFontList.AppendElement(kFontAppleBraille);
        break;
      case 0x31:
        aFontList.AppendElement(kFontHiraginoSansGB);
        break;
      case 0x4d:
        aFontList.AppendElement(kFontAppleSymbols);
        break;
      case 0xa0:  // Yi
      case 0xa1:
      case 0xa2:
      case 0xa3:
      case 0xa4:
        aFontList.AppendElement(kFontSTHeiti);
        break;
      case 0xa6:
      case 0xa7:
        aFontList.AppendElement(kFontGeneva);
        aFontList.AppendElement(kFontAppleSymbols);
        break;
      case 0xab:
        aFontList.AppendElement(kFontKefa);
        break;
      case 0xfc:
      case 0xff:
        aFontList.AppendElement(kFontAppleSymbols);
        break;
      default:
        break;
    }
  }

  // Arial Unicode MS has lots of glyphs for obscure, use it as a last resort
  aFontList.AppendElement(kFontArialUnicodeMS);
}

/*static*/
void gfxPlatformMac::LookupSystemFont(
    mozilla::LookAndFeel::FontID aSystemFontID, nsACString& aSystemFontName,
    gfxFontStyle& aFontStyle) {
  gfxMacPlatformFontList* pfl = gfxMacPlatformFontList::PlatformFontList();
  return pfl->LookupSystemFont(aSystemFontID, aSystemFontName, aFontStyle);
}

uint32_t gfxPlatformMac::ReadAntiAliasingThreshold() {
  uint32_t threshold = 0;  // default == no threshold

  // first read prefs flag to determine whether to use the setting or not
  bool useAntiAliasingThreshold =
      Preferences::GetBool("gfx.use_text_smoothing_setting", false);

  // if the pref setting is disabled, return 0 which effectively disables this
  // feature
  if (!useAntiAliasingThreshold) return threshold;

  // value set via Appearance pref panel, "Turn off text smoothing for font
  // sizes xxx and smaller"
  CFNumberRef prefValue = (CFNumberRef)CFPreferencesCopyAppValue(
      CFSTR("AppleAntiAliasingThreshold"), kCFPreferencesCurrentApplication);

  if (prefValue) {
    if (!CFNumberGetValue(prefValue, kCFNumberIntType, &threshold)) {
      threshold = 0;
    }
    CFRelease(prefValue);
  }

  return threshold;
}

bool gfxPlatformMac::AccelerateLayersByDefault() { return true; }

// This is the renderer output callback function, called on the vsync thread
static CVReturn VsyncCallback(CVDisplayLinkRef aDisplayLink,
                              const CVTimeStamp* aNow,
                              const CVTimeStamp* aOutputTime,
                              CVOptionFlags aFlagsIn, CVOptionFlags* aFlagsOut,
                              void* aDisplayLinkContext);

class OSXVsyncSource final : public VsyncSource {
 public:
  OSXVsyncSource() {}

  Display& GetGlobalDisplay() override { return mGlobalDisplay; }

  class OSXDisplay final : public VsyncSource::Display {
   public:
    OSXDisplay() : mDisplayLink(nullptr) {
      MOZ_ASSERT(NS_IsMainThread());
      mTimer = NS_NewTimer();
    }

    virtual ~OSXDisplay() { MOZ_ASSERT(NS_IsMainThread()); }

    static void RetryEnableVsync(nsITimer* aTimer, void* aOsxDisplay) {
      MOZ_ASSERT(NS_IsMainThread());
      OSXDisplay* osxDisplay = static_cast<OSXDisplay*>(aOsxDisplay);
      MOZ_ASSERT(osxDisplay);
      osxDisplay->EnableVsync();
    }

    void EnableVsync() override {
      MOZ_ASSERT(NS_IsMainThread());
      if (IsVsyncEnabled()) {
        return;
      }

      // Create a display link capable of being used with all active displays
      // TODO: See if we need to create an active DisplayLink for each monitor
      // in multi-monitor situations. According to the docs, it is compatible
      // with all displays running on the computer But if we have different
      // monitors at different display rates, we may hit issues.
      if (CVDisplayLinkCreateWithActiveCGDisplays(&mDisplayLink) !=
          kCVReturnSuccess) {
        NS_WARNING(
            "Could not create a display link with all active displays. "
            "Retrying");
        CVDisplayLinkRelease(mDisplayLink);
        mDisplayLink = nullptr;

        // bug 1142708 - When coming back from sleep,
        // or when changing displays, active displays may not be ready yet,
        // even if listening for the kIOMessageSystemHasPoweredOn event
        // from OS X sleep notifications.
        // Active displays are those that are drawable.
        // bug 1144638 - When changing display configurations and getting
        // notifications from CGDisplayReconfigurationCallBack, the
        // callback gets called twice for each active display
        // so it's difficult to know when all displays are active.
        // Instead, try again soon. The delay is arbitrary. 100ms chosen
        // because on a late 2013 15" retina, it takes about that
        // long to come back up from sleep.
        uint32_t delay = 100;
        mTimer->InitWithNamedFuncCallback(RetryEnableVsync, this, delay,
                                          nsITimer::TYPE_ONE_SHOT,
                                          "RetryEnableVsync");
        return;
      }

      if (CVDisplayLinkSetOutputCallback(mDisplayLink, &VsyncCallback, this) !=
          kCVReturnSuccess) {
        NS_WARNING("Could not set displaylink output callback");
        CVDisplayLinkRelease(mDisplayLink);
        mDisplayLink = nullptr;
        return;
      }

      mPreviousTimestamp = TimeStamp::Now();
      if (CVDisplayLinkStart(mDisplayLink) != kCVReturnSuccess) {
        NS_WARNING("Could not activate the display link");
        CVDisplayLinkRelease(mDisplayLink);
        mDisplayLink = nullptr;
      }

      CVTime vsyncRate =
          CVDisplayLinkGetNominalOutputVideoRefreshPeriod(mDisplayLink);
      if (vsyncRate.flags & kCVTimeIsIndefinite) {
        NS_WARNING("Could not get vsync rate, setting to 60.");
        mVsyncRate = TimeDuration::FromMilliseconds(1000.0 / 60.0);
      } else {
        int64_t timeValue = vsyncRate.timeValue;
        int64_t timeScale = vsyncRate.timeScale;
        const int milliseconds = 1000;
        float rateInMs = ((double)timeValue / (double)timeScale) * milliseconds;
        mVsyncRate = TimeDuration::FromMilliseconds(rateInMs);
      }
    }

    void DisableVsync() override {
      MOZ_ASSERT(NS_IsMainThread());
      if (!IsVsyncEnabled()) {
        return;
      }

      // Release the display link
      if (mDisplayLink) {
        CVDisplayLinkRelease(mDisplayLink);
        mDisplayLink = nullptr;
      }
    }

    bool IsVsyncEnabled() override {
      MOZ_ASSERT(NS_IsMainThread());
      return mDisplayLink != nullptr;
    }

    TimeDuration GetVsyncRate() override { return mVsyncRate; }

    void Shutdown() override {
      MOZ_ASSERT(NS_IsMainThread());
      mTimer->Cancel();
      mTimer = nullptr;
      DisableVsync();
    }

    // The vsync timestamps given by the CVDisplayLinkCallback are
    // in the future for the NEXT frame. Large parts of Gecko, such
    // as animations assume a timestamp at either now or in the past.
    // Normalize the timestamps given to the VsyncDispatchers to the vsync
    // that just occured, not the vsync that is upcoming.
    TimeStamp mPreviousTimestamp;

   private:
    // Manages the display link render thread
    CVDisplayLinkRef mDisplayLink;
    RefPtr<nsITimer> mTimer;
    TimeDuration mVsyncRate;
  };  // OSXDisplay

 private:
  virtual ~OSXVsyncSource() = default;

  OSXDisplay mGlobalDisplay;
};  // OSXVsyncSource

static CVReturn VsyncCallback(CVDisplayLinkRef aDisplayLink,
                              const CVTimeStamp* aNow,
                              const CVTimeStamp* aOutputTime,
                              CVOptionFlags aFlagsIn, CVOptionFlags* aFlagsOut,
                              void* aDisplayLinkContext) {
  // Executed on OS X hardware vsync thread
  OSXVsyncSource::OSXDisplay* display =
      (OSXVsyncSource::OSXDisplay*)aDisplayLinkContext;
  int64_t nextVsyncTimestamp = aOutputTime->hostTime;

  mozilla::TimeStamp nextVsync =
      mozilla::TimeStamp::FromSystemTime(nextVsyncTimestamp);
  mozilla::TimeStamp previousVsync = display->mPreviousTimestamp;
  mozilla::TimeStamp now = TimeStamp::Now();

  // Snow leopard sometimes sends vsync timestamps very far in the past.
  // Normalize the vsync timestamps to now.
  if (nextVsync <= previousVsync) {
    nextVsync = now;
    previousVsync = now;
  } else if (now < previousVsync) {
    // Bug 1158321 - The VsyncCallback can sometimes execute before the reported
    // vsync time. In those cases, normalize the timestamp to Now() as sending
    // timestamps in the future has undefined behavior. See the comment above
    // OSXDisplay::mPreviousTimestamp
    previousVsync = now;
  }

  display->mPreviousTimestamp = nextVsync;

  display->NotifyVsync(previousVsync);
  return kCVReturnSuccess;
}

already_AddRefed<mozilla::gfx::VsyncSource>
gfxPlatformMac::CreateHardwareVsyncSource() {
  RefPtr<VsyncSource> osxVsyncSource = new OSXVsyncSource();
  VsyncSource::Display& primaryDisplay = osxVsyncSource->GetGlobalDisplay();
  primaryDisplay.EnableVsync();
  if (!primaryDisplay.IsVsyncEnabled()) {
    NS_WARNING(
        "OS X Vsync source not enabled. Falling back to software vsync.");
    return gfxPlatform::CreateHardwareVsyncSource();
  }

  primaryDisplay.DisableVsync();
  return osxVsyncSource.forget();
}

void gfxPlatformMac::GetPlatformCMSOutputProfile(void*& mem, size_t& size) {
  mem = nullptr;
  size = 0;

  CGColorSpaceRef cspace = ::CGDisplayCopyColorSpace(::CGMainDisplayID());
  if (!cspace) {
    cspace = ::CGColorSpaceCreateDeviceRGB();
  }
  if (!cspace) {
    return;
  }

  CFDataRef iccp = ::CGColorSpaceCopyICCProfile(cspace);

  ::CFRelease(cspace);

  if (!iccp) {
    return;
  }

  // copy to external buffer
  size = static_cast<size_t>(::CFDataGetLength(iccp));
  if (size > 0) {
    void* data = malloc(size);
    if (data) {
      memcpy(data, ::CFDataGetBytePtr(iccp), size);
      mem = data;
    } else {
      size = 0;
    }
  }

  ::CFRelease(iccp);
}

bool gfxPlatformMac::CheckVariationFontSupport() {
  // We don't allow variation fonts to be enabled before 10.13,
  // as although the Core Text APIs existed, they are known to be
  // fairly buggy.
  // (Note that Safari also requires 10.13 for variation-font support.)
  return nsCocoaFeatures::OnHighSierraOrLater();
}