/* -*- 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 "mozilla/dom/FileSystemUtils.h"

namespace mozilla {

namespace dom {

namespace {

bool TokenizerIgnoreNothing(char16_t /* aChar */) { return false; }

}  // anonymous namespace

/* static */ bool FileSystemUtils::IsDescendantPath(

    const nsAString& aPath, const nsAString& aDescendantPath) {

  // Check the sub-directory path to see if it has the parent path as prefix.

  if (!aDescendantPath.Equals(aPath) &&

      !StringBeginsWith(aDescendantPath, aPath)) {

    return false;

  }

  return true;

}

/* static */ bool FileSystemUtils::IsValidRelativeDOMPath(

    const nsAString& aPath, nsTArray<nsString>& aParts) {

  // We don't allow empty relative path to access the root.

  if (aPath.IsEmpty()) {

    return false;

  }

  // Leading and trailing "/" are not allowed.

  if (aPath.First() == FILESYSTEM_DOM_PATH_SEPARATOR_CHAR ||

      aPath.Last() == FILESYSTEM_DOM_PATH_SEPARATOR_CHAR) {

    return false;

  }

  NS_NAMED_LITERAL_STRING(kCurrentDir, ".");

  NS_NAMED_LITERAL_STRING(kParentDir, "..");

  // Split path and check each path component.

  nsCharSeparatedTokenizerTemplate<TokenizerIgnoreNothing> tokenizer(

      aPath, FILESYSTEM_DOM_PATH_SEPARATOR_CHAR);

  while (tokenizer.hasMoreTokens()) {

    nsDependentSubstring pathComponent = tokenizer.nextToken();

    // The path containing empty components, such as "foo//bar", is invalid.

    // We don't allow paths, such as "../foo", "foo/./bar" and "foo/../bar",

    // to walk up the directory.

    if (pathComponent.IsEmpty() || pathComponent.Equals(kCurrentDir) ||

        pathComponent.Equals(kParentDir)) {

      return false;

    }

    aParts.AppendElement(pathComponent);

  }

  return true;

}

/* static */ nsresult FileSystemUtils::DispatchRunnable(

    nsIGlobalObject* aGlobal, already_AddRefed<nsIRunnable>&& aRunnable) {

  nsCOMPtr<nsIRunnable> runnable = aRunnable;

  nsCOMPtr<nsIEventTarget> target;

  if (!aGlobal) {

    target = SystemGroup::EventTargetFor(TaskCategory::Other);

  } else {

    target = aGlobal->EventTargetFor(TaskCategory::Other);

  }

  MOZ_ASSERT(target);

  nsresult rv = target->Dispatch(runnable.forget(), NS_DISPATCH_NORMAL);

  if (NS_WARN_IF(NS_FAILED(rv))) {

    return rv;

  }

  return NS_OK;

}

}  // namespace dom

}  // namespace mozilla