SnapManager implementation using V8 Extras - {WIP}

third_party/WebKit/Source/core/page/scrolling/snap/SnapManagerBridge.cpp

+// Copyright 2015 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.
+
+#include "core/page/scrolling/snap/SnapManagerBridge.h"
+
+#include "bindings/core/v8/V8ObjectConstructor.h"
+#include "core/dom/Document.h"
+#include "core/dom/Element.h"
+#include "core/frame/DOMWindow.h"
+#include "core/frame/LocalDOMWindow.h"
+#include "core/layout/LayoutBox.h"
+#include "wtf/Vector.h"
+
+#include <v8.h>
+
+namespace blink {
+
+SnapManagerBridge::SnapManagerBridge(const Document* document)
+    : m_document(document)
+{
+}
+
+void SnapManagerBridge::maybeCreateSnapManagerInstance()
+{
+    if (!m_instance.isEmpty())
+        return;
+
+    m_scriptState = ScriptState::forMainWorld(m_document->frame());
+    ScriptState::Scope scope(m_scriptState.get());
+
+    // Pass in window
+    v8::Local<v8::Value> args[] = {toV8(m_document->domWindow(), m_scriptState->context()->Global(), m_scriptState->isolate())};
+    v8::MaybeLocal<v8::Value> result = V8ScriptRunner::callExtra(m_scriptState.get(), "CreateSnapManager", args);
+
+    v8::Local<v8::Value> managerInstance;
+    if (result.ToLocal(&managerInstance)) {
+        m_instance = ScriptValue(m_scriptState.get(), managerInstance.As<v8::Object>());
+    } else {
+        NOTREACHED() << "Couldn't instantiate SnapManager";
+    }
+}
+
+void SnapManagerBridge::didUpdateSnapOffsets(const LayoutBox& box, SnapOffsets offsets)
+{
+    maybeCreateSnapManagerInstance();
+    Node* container = box.node();
+
+    ScriptState::Scope scope(m_scriptState.get());
+    v8::Local<v8::Value> containerWrapper = toV8(container, m_scriptState->context()->Global(), m_scriptState->isolate());
+    v8::Local<v8::Value> horizontalOffsetsWrapper = toV8(offsets.horizontal, m_scriptState->context()->Global(), m_scriptState->isolate());
+    v8::Local<v8::Value> verticalOffsetsWrapper = toV8(offsets.vertical, m_scriptState->context()->Global(), m_scriptState->isolate());
+
+    v8::Local<v8::Value> args[] = { m_instance.v8Value(), containerWrapper, horizontalOffsetsWrapper, verticalOffsetsWrapper};
+
+    V8ScriptRunner::callExtra(m_scriptState.get(), "UpdateSnapContainer", args);
+}
+
+} // namespace blink
+