/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* vim: set ts=8 sts=2 et sw=2 tw=80: */
/* 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 "URLWorker.h"

#include "mozilla/dom/Blob.h"
#include "mozilla/dom/BlobURLProtocolHandler.h"
#include "mozilla/dom/WorkerPrivate.h"
#include "mozilla/dom/WorkerRunnable.h"
#include "mozilla/dom/WorkerScope.h"

namespace mozilla {
namespace dom {

// This class creates an URL from a DOM Blob on the main thread.
class CreateURLRunnable : public WorkerMainThreadRunnable {
 private:
  BlobImpl* mBlobImpl;
  nsAString& mURL;

 public:
  CreateURLRunnable(WorkerPrivate* aWorkerPrivate, BlobImpl* aBlobImpl,
                    nsAString& aURL)
      : WorkerMainThreadRunnable(aWorkerPrivate,
                                 NS_LITERAL_CSTRING("URL :: CreateURL")),
        mBlobImpl(aBlobImpl),
        mURL(aURL) {
    MOZ_ASSERT(aBlobImpl);

    DebugOnly<bool> isMutable;
    MOZ_ASSERT(NS_SUCCEEDED(aBlobImpl->GetMutable(&isMutable)));
    MOZ_ASSERT(!isMutable);
  }

  bool MainThreadRun() override {
    using namespace mozilla::ipc;

    AssertIsOnMainThread();

    DebugOnly<bool> isMutable;
    MOZ_ASSERT(NS_SUCCEEDED(mBlobImpl->GetMutable(&isMutable)));
    MOZ_ASSERT(!isMutable);

    nsCOMPtr<nsIPrincipal> principal = mWorkerPrivate->GetPrincipal();

    nsAutoCString url;
    nsresult rv =
        BlobURLProtocolHandler::AddDataEntry(mBlobImpl, principal, url);

    if (NS_FAILED(rv)) {
      NS_WARNING("Failed to add data entry for the blob!");
      SetDOMStringToNull(mURL);
      return false;
    }

    if (!mWorkerPrivate->IsSharedWorker() &&
        !mWorkerPrivate->IsServiceWorker()) {
      // Walk up to top worker object.
      WorkerPrivate* wp = mWorkerPrivate;
      while (WorkerPrivate* parent = wp->GetParent()) {
        wp = parent;
      }

      nsCOMPtr<nsIScriptContext> sc = wp->GetScriptContext();
      // We could not have a ScriptContext in JSM code. In this case, we leak.
      if (sc) {
        nsCOMPtr<nsIGlobalObject> global = sc->GetGlobalObject();
        MOZ_ASSERT(global);

        global->RegisterHostObjectURI(url);
      }
    }

    mURL = NS_ConvertUTF8toUTF16(url);
    return true;
  }
};

// This class revokes an URL on the main thread.
class RevokeURLRunnable : public WorkerMainThreadRunnable {
 private:
  const nsString mURL;

 public:
  RevokeURLRunnable(WorkerPrivate* aWorkerPrivate, const nsAString& aURL)
      : WorkerMainThreadRunnable(aWorkerPrivate,
                                 NS_LITERAL_CSTRING("URL :: RevokeURL")),
        mURL(aURL) {}

  bool MainThreadRun() override {
    AssertIsOnMainThread();

    NS_ConvertUTF16toUTF8 url(mURL);

    nsIPrincipal* urlPrincipal =
        BlobURLProtocolHandler::GetDataEntryPrincipal(url);

    nsCOMPtr<nsIPrincipal> principal = mWorkerPrivate->GetPrincipal();

    bool subsumes;
    if (urlPrincipal &&
        NS_SUCCEEDED(principal->Subsumes(urlPrincipal, &subsumes)) &&
        subsumes) {
      BlobURLProtocolHandler::RemoveDataEntry(url);
    }

    if (!mWorkerPrivate->IsSharedWorker() &&
        !mWorkerPrivate->IsServiceWorker()) {
      // Walk up to top worker object.
      WorkerPrivate* wp = mWorkerPrivate;
      while (WorkerPrivate* parent = wp->GetParent()) {
        wp = parent;
      }

      nsCOMPtr<nsIScriptContext> sc = wp->GetScriptContext();
      // We could not have a ScriptContext in JSM code. In this case, we leak.
      if (sc) {
        nsCOMPtr<nsIGlobalObject> global = sc->GetGlobalObject();
        MOZ_ASSERT(global);

        global->UnregisterHostObjectURI(url);
      }
    }

    return true;
  }
};

// This class checks if an URL is valid on the main thread.
class IsValidURLRunnable : public WorkerMainThreadRunnable {
 private:
  const nsString mURL;
  bool mValid;

 public:
  IsValidURLRunnable(WorkerPrivate* aWorkerPrivate, const nsAString& aURL)
      : WorkerMainThreadRunnable(aWorkerPrivate,
                                 NS_LITERAL_CSTRING("URL :: IsValidURL")),
        mURL(aURL),
        mValid(false) {}

  bool MainThreadRun() override {
    AssertIsOnMainThread();

    NS_ConvertUTF16toUTF8 url(mURL);
    mValid = BlobURLProtocolHandler::HasDataEntry(url);

    return true;
  }

  bool IsValidURL() const { return mValid; }
};

/* static */
void URLWorker::CreateObjectURL(const GlobalObject& aGlobal, Blob& aBlob,
                                nsAString& aResult, mozilla::ErrorResult& aRv) {
  JSContext* cx = aGlobal.Context();
  WorkerPrivate* workerPrivate = GetWorkerPrivateFromContext(cx);

  RefPtr<BlobImpl> blobImpl = aBlob.Impl();
  MOZ_ASSERT(blobImpl);

  aRv = blobImpl->SetMutable(false);
  if (NS_WARN_IF(aRv.Failed())) {
    return;
  }

  RefPtr<CreateURLRunnable> runnable =
      new CreateURLRunnable(workerPrivate, blobImpl, aResult);

  runnable->Dispatch(Canceling, aRv);
  if (NS_WARN_IF(aRv.Failed())) {
    return;
  }

  if (workerPrivate->IsSharedWorker() || workerPrivate->IsServiceWorker()) {
    WorkerGlobalScope* scope = workerPrivate->GlobalScope();
    MOZ_ASSERT(scope);

    scope->RegisterHostObjectURI(NS_ConvertUTF16toUTF8(aResult));
  }
}

/* static */
void URLWorker::RevokeObjectURL(const GlobalObject& aGlobal,
                                const nsAString& aUrl, ErrorResult& aRv) {
  JSContext* cx = aGlobal.Context();
  WorkerPrivate* workerPrivate = GetWorkerPrivateFromContext(cx);

  RefPtr<RevokeURLRunnable> runnable =
      new RevokeURLRunnable(workerPrivate, aUrl);

  runnable->Dispatch(Canceling, aRv);
  if (NS_WARN_IF(aRv.Failed())) {
    return;
  }

  if (workerPrivate->IsSharedWorker() || workerPrivate->IsServiceWorker()) {
    WorkerGlobalScope* scope = workerPrivate->GlobalScope();
    MOZ_ASSERT(scope);

    scope->UnregisterHostObjectURI(NS_ConvertUTF16toUTF8(aUrl));
  }
}

/* static */
bool URLWorker::IsValidURL(const GlobalObject& aGlobal, const nsAString& aUrl,
                           ErrorResult& aRv) {
  JSContext* cx = aGlobal.Context();
  WorkerPrivate* workerPrivate = GetWorkerPrivateFromContext(cx);

  RefPtr<IsValidURLRunnable> runnable =
      new IsValidURLRunnable(workerPrivate, aUrl);

  runnable->Dispatch(Canceling, aRv);
  if (NS_WARN_IF(aRv.Failed())) {
    return false;
  }

  return runnable->IsValidURL();
}

}  // namespace dom
}  // namespace mozilla