// Copyright 2016 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 "bindings/core/v8/V8IntersectionObserverCallback.h"

#include "bindings/core/v8/ScriptController.h"
#include "bindings/core/v8/V8Binding.h"
#include "bindings/core/v8/V8IntersectionObserver.h"
#include "bindings/core/v8/V8PrivateProperty.h"
#include "core/dom/ExecutionContext.h"
#include "wtf/Assertions.h"

namespace blink {

V8IntersectionObserverCallback::V8IntersectionObserverCallback(
    v8::Local<v8::Function> callback,
    v8::Local<v8::Object> owner,
    ScriptState* scriptState)
    : ActiveDOMCallback(scriptState->getExecutionContext()),
      m_callback(scriptState->isolate(), callback),
      m_scriptState(scriptState) {
  V8PrivateProperty::getIntersectionObserverCallback(scriptState->isolate())
      .set(scriptState->context(), owner, callback);
  m_callback.setPhantom();
}

V8IntersectionObserverCallback::~V8IntersectionObserverCallback() {}

void V8IntersectionObserverCallback::handleEvent(
    const HeapVector<Member<IntersectionObserverEntry>>& entries,
    IntersectionObserver& observer) {
  if (!canInvokeCallback())
    return;

  if (!m_scriptState->contextIsValid())
    return;
  ScriptState::Scope scope(m_scriptState.get());

  if (m_callback.isEmpty())
    return;
  v8::Local<v8::Value> observerHandle = toV8(
      &observer, m_scriptState->context()->Global(), m_scriptState->isolate());
  if (!observerHandle->IsObject())
    return;

  v8::Local<v8::Object> thisObject =
      v8::Local<v8::Object>::Cast(observerHandle);
  v8::Local<v8::Value> entriesHandle = toV8(
      entries, m_scriptState->context()->Global(), m_scriptState->isolate());
  if (entriesHandle.IsEmpty()) {
    return;
  }
  v8::Local<v8::Value> argv[] = {entriesHandle, observerHandle};

  v8::TryCatch exceptionCatcher(m_scriptState->isolate());
  exceptionCatcher.SetVerbose(true);
  V8ScriptRunner::callFunction(m_callback.newLocal(m_scriptState->isolate()),
                               m_scriptState->getExecutionContext(), thisObject,
                               2, argv, m_scriptState->isolate());
}

DEFINE_TRACE(V8IntersectionObserverCallback) {
  IntersectionObserverCallback::trace(visitor);
  ActiveDOMCallback::trace(visitor);
}

}  // namespace blink