From f27c48490f244f1f930c0c396d68799fb6633042 Mon Sep 17 00:00:00 2001
From: Kartikaya Gupta <kgupta@mozilla.com>
Date: Mon, 25 Jul 2016 17:33:09 -0700
Subject: [PATCH] Bug 1288187 - Allow synthesizing widget touch events on OS X.
 r=mstange

MozReview-Commit-ID: AGvZQZtbPh
---
 widget/cocoa/nsChildView.h  | 10 ++++++++
 widget/cocoa/nsChildView.mm | 48 +++++++++++++++++++++++++++++++++++++
 2 files changed, 58 insertions(+)

diff --git a/widget/cocoa/nsChildView.h b/widget/cocoa/nsChildView.h
index 2e62f4251a33..c814fc00d58a 100644
--- a/widget/cocoa/nsChildView.h
+++ b/widget/cocoa/nsChildView.h
@@ -419,6 +419,12 @@ public:
                                                     uint32_t aModifierFlags,
                                                     uint32_t aAdditionalFlags,
                                                     nsIObserver* aObserver) override;
+  virtual nsresult SynthesizeNativeTouchPoint(uint32_t aPointerId,
+                                              TouchPointerState aPointerState,
+                                              LayoutDeviceIntPoint aPoint,
+                                              double aPointerPressure,
+                                              uint32_t aPointerOrientation,
+                                              nsIObserver* aObserver) override;
 
   // Mac specific methods
 
@@ -646,6 +652,10 @@ protected:
   static uint32_t sLastInputEventCount;
 
   void ReleaseTitlebarCGContext();
+
+  // This is used by SynthesizeNativeTouchPoint to maintain state between
+  // multiple synthesized points
+  mozilla::UniquePtr<mozilla::MultiTouchInput> mSynthesizedTouchInput;
 };
 
 #endif // nsChildView_h_
diff --git a/widget/cocoa/nsChildView.mm b/widget/cocoa/nsChildView.mm
index 9f12a334f586..83c162392778 100644
--- a/widget/cocoa/nsChildView.mm
+++ b/widget/cocoa/nsChildView.mm
@@ -1184,6 +1184,54 @@ nsresult nsChildView::SynthesizeNativeMouseScrollEvent(mozilla::LayoutDeviceIntP
   NS_OBJC_END_TRY_ABORT_BLOCK_NSRESULT;
 }
 
+nsresult nsChildView::SynthesizeNativeTouchPoint(uint32_t aPointerId,
+                                                 TouchPointerState aPointerState,
+                                                 mozilla::LayoutDeviceIntPoint aPoint,
+                                                 double aPointerPressure,
+                                                 uint32_t aPointerOrientation,
+                                                 nsIObserver* aObserver)
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK_NSRESULT;
+
+  AutoObserverNotifier notifier(aObserver, "touchpoint");
+
+  MOZ_ASSERT(NS_IsMainThread());
+  if (aPointerState == TOUCH_HOVER) {
+    return NS_ERROR_UNEXPECTED;
+  }
+
+  if (!mSynthesizedTouchInput) {
+    mSynthesizedTouchInput = MakeUnique<MultiTouchInput>();
+  }
+
+  LayoutDeviceIntPoint pointInWindow = aPoint - WidgetToScreenOffset();
+  MultiTouchInput inputToDispatch = UpdateSynthesizedTouchState(
+      mSynthesizedTouchInput.get(), aPointerId, aPointerState,
+      pointInWindow, aPointerPressure, aPointerOrientation);
+
+  if (mAPZC) {
+    uint64_t inputBlockId = 0;
+    ScrollableLayerGuid guid;
+
+    nsEventStatus result = mAPZC->ReceiveInputEvent(inputToDispatch, &guid, &inputBlockId);
+    if (result == nsEventStatus_eConsumeNoDefault) {
+      return NS_OK;
+    }
+
+    WidgetTouchEvent event = inputToDispatch.ToWidgetTouchEvent(this);
+    ProcessUntransformedAPZEvent(&event, guid, inputBlockId, result);
+  } else {
+    WidgetTouchEvent event = inputToDispatch.ToWidgetTouchEvent(this);
+
+    nsEventStatus status;
+    DispatchEvent(&event, status);
+  }
+
+  return NS_OK;;
+
+  NS_OBJC_END_TRY_ABORT_BLOCK_NSRESULT;
+}
+
 // First argument has to be an NSMenu representing the application's top-level
 // menu bar. The returned item is *not* retained.
 static NSMenuItem* NativeMenuItemWithLocation(NSMenu* menubar, NSString* locationString)