// 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 "extensions/renderer/api_binding_test.h"

#include "base/memory/ptr_util.h"
#include "base/threading/thread_task_runner_handle.h"
#include "gin/array_buffer.h"
#include "gin/public/context_holder.h"
#include "gin/public/isolate_holder.h"
#include "gin/v8_initializer.h"

namespace extensions {

APIBindingTest::APIBindingTest() {}
APIBindingTest::~APIBindingTest() {}

v8::ExtensionConfiguration* APIBindingTest::GetV8ExtensionConfiguration() {
  return nullptr;
}

void APIBindingTest::SetUp() {
  // Much of this initialization is stolen from the somewhat-similar
  // gin::V8Test.
#ifdef V8_USE_EXTERNAL_STARTUP_DATA
  gin::V8Initializer::LoadV8Snapshot();
  gin::V8Initializer::LoadV8Natives();
#endif

  gin::IsolateHolder::Initialize(gin::IsolateHolder::kStrictMode,
                                 gin::IsolateHolder::kStableV8Extras,
                                 gin::ArrayBufferAllocator::SharedInstance());

  isolate_holder_ =
      base::MakeUnique<gin::IsolateHolder>(base::ThreadTaskRunnerHandle::Get());
  isolate()->Enter();

  v8::HandleScope handle_scope(isolate());
  v8::Local<v8::Context> context =
      v8::Context::New(isolate(), GetV8ExtensionConfiguration());
  context->Enter();
  context_holder_ = base::MakeUnique<gin::ContextHolder>(isolate());
  context_holder_->SetContext(context);
}

void APIBindingTest::TearDown() {
  auto run_garbage_collection = [this]() {
    // '5' is a magic number stolen from Blink; arbitrarily large enough to
    // hopefully clean up all the various paths.
    for (int i = 0; i < 5; ++i) {
      isolate()->RequestGarbageCollectionForTesting(
          v8::Isolate::kFullGarbageCollection);
    }
  };

  if (context_holder_) {
    // Check for leaks - a weak handle to a context is invalidated on context
    // destruction, so resetting the context should reset the handle.
    v8::Global<v8::Context> weak_context;
    {
      v8::HandleScope handle_scope(isolate());
      v8::Local<v8::Context> context = ContextLocal();
      weak_context.Reset(isolate(), context);
      weak_context.SetWeak();
      context->Exit();
    }
    context_holder_.reset();

    // Garbage collect everything so that we find any issues where we might be
    // double-freeing.
    run_garbage_collection();

    // The context should have been deleted.
    // (ASSERT_TRUE is not used, so that Isolate::Exit is still called.)
    EXPECT_TRUE(weak_context.IsEmpty());
  } else {
    // The context was already deleted (as through DisposeContext()), but we
    // still need to garbage collect.
    run_garbage_collection();
  }

  isolate()->Exit();
  isolate_holder_.reset();
}

v8::Local<v8::Context> APIBindingTest::ContextLocal() {
  return context_holder_->context();
}

void APIBindingTest::DisposeContext() {
  context_holder_.reset();
}

v8::Isolate* APIBindingTest::isolate() {
  return isolate_holder_->isolate();
}

}  // namespace extensions