/*
 * Copyright (C) 2010 Google Inc. All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are
 * met:
 *
 *     * Redistributions of source code must retain the above copyright
 * notice, this list of conditions and the following disclaimer.
 *     * Redistributions in binary form must reproduce the above
 * copyright notice, this list of conditions and the following disclaimer
 * in the documentation and/or other materials provided with the
 * distribution.
 *     * Neither the name of Google Inc. nor the names of its
 * contributors may be used to endorse or promote products derived from
 * this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */

#include "third_party/blink/renderer/modules/filesystem/dom_file_system.h"

#include <memory>
#include <utility>

#include "storage/common/database/database_identifier.h"
#include "third_party/blink/renderer/core/probe/async_task_context.h"
#include "third_party/blink/renderer/core/probe/core_probes.h"
#include "third_party/blink/renderer/modules/filesystem/directory_entry.h"
#include "third_party/blink/renderer/modules/filesystem/dom_file_path.h"
#include "third_party/blink/renderer/modules/filesystem/file_entry.h"
#include "third_party/blink/renderer/modules/filesystem/file_system_callbacks.h"
#include "third_party/blink/renderer/modules/filesystem/file_system_dispatcher.h"
#include "third_party/blink/renderer/modules/filesystem/file_writer.h"
#include "third_party/blink/renderer/platform/weborigin/security_origin.h"
#include "third_party/blink/renderer/platform/wtf/functional.h"
#include "third_party/blink/renderer/platform/wtf/text/string_builder.h"
#include "third_party/blink/renderer/platform/wtf/text/wtf_string.h"

namespace blink {

namespace {

void RunCallback(ExecutionContext* execution_context,
                 base::OnceClosure task,
                 std::unique_ptr<probe::AsyncTaskContext> async_task_context) {
  if (!execution_context)
    return;
  DCHECK(execution_context->IsContextThread());
  probe::AsyncTask async_task(execution_context, async_task_context.get());
  std::move(task).Run();
}

}  // namespace

DOMFileSystem* DOMFileSystem::CreateIsolatedFileSystem(
    ExecutionContext* context,
    const String& filesystem_id) {
  if (filesystem_id.empty())
    return nullptr;

  StringBuilder filesystem_name;
  filesystem_name.Append(String::FromUtf8(storage::GetIdentifierFromOrigin(
      context->GetSecurityOrigin()->ToUrlOrigin())));
  filesystem_name.Append(":Isolated_");
  filesystem_name.Append(filesystem_id);

  // The rootURL created here is going to be attached to each filesystem request
  // and is to be validated each time the request is being handled.
  StringBuilder root_url;
  root_url.Append("filesystem:");
  root_url.Append(context->GetSecurityOrigin()->ToString());
  root_url.Append('/');
  root_url.Append(kIsolatedPathPrefix);
  root_url.Append('/');
  root_url.Append(filesystem_id);
  root_url.Append('/');

  return MakeGarbageCollected<DOMFileSystem>(
      context, filesystem_name.ToString(),
      mojom::blink::FileSystemType::kIsolated, KURL(root_url));
}

DOMFileSystem::DOMFileSystem(ExecutionContext* context,
                             const String& name,
                             mojom::blink::FileSystemType type,
                             const KURL& root_url)
    : DOMFileSystemBase(context, name, type, root_url),
      ActiveScriptWrappable<DOMFileSystem>({}),
      ExecutionContextClient(context),
      number_of_pending_callbacks_(0),
      root_entry_(
          MakeGarbageCollected<DirectoryEntry>(this, DOMFilePath::kRoot)) {}

DirectoryEntry* DOMFileSystem::root() const {
  return root_entry_.Get();
}

void DOMFileSystem::AddPendingCallbacks() {
  ++number_of_pending_callbacks_;
}

void DOMFileSystem::RemovePendingCallbacks() {
  DCHECK_GT(number_of_pending_callbacks_, 0);
  --number_of_pending_callbacks_;
}

bool DOMFileSystem::HasPendingActivity() const {
  DCHECK_GE(number_of_pending_callbacks_, 0);
  return number_of_pending_callbacks_;
}

void DOMFileSystem::ReportError(ErrorCallback error_callback,
                                base::File::Error error) {
  ReportError(GetExecutionContext(), std::move(error_callback), error);
}

void DOMFileSystem::ReportError(ExecutionContext* execution_context,
                                ErrorCallback error_callback,
                                base::File::Error error) {
  if (!error_callback)
    return;
  ScheduleCallback(execution_context,
                   blink::BindOnce(std::move(error_callback), error));
}

void DOMFileSystem::CreateWriter(
    const FileEntry* file_entry,
    FileWriterCallbacks::SuccessCallback success_callback,
    FileWriterCallbacks::ErrorCallback error_callback) {
  DCHECK(file_entry);

  auto* file_writer = MakeGarbageCollected<FileWriter>(GetExecutionContext());
  auto callbacks = std::make_unique<FileWriterCallbacks>(
      file_writer, std::move(success_callback), std::move(error_callback),
      context_);
  FileSystemDispatcher::From(context_).InitializeFileWriter(
      CreateFileSystemURL(file_entry), std::move(callbacks));
}

void DOMFileSystem::CreateFile(
    const FileEntry* file_entry,
    SnapshotFileCallback::SuccessCallback success_callback,
    SnapshotFileCallback::ErrorCallback error_callback) {
  KURL file_system_url = CreateFileSystemURL(file_entry);

  FileSystemDispatcher::From(context_).CreateSnapshotFile(
      file_system_url,
      std::make_unique<SnapshotFileCallback>(
          this, file_entry->name(), file_system_url,
          std::move(success_callback), std::move(error_callback), context_));
}

void DOMFileSystem::ScheduleCallback(ExecutionContext* execution_context,
                                     base::OnceClosure task) {
  if (!execution_context)
    return;

  DCHECK(execution_context->IsContextThread());

  auto async_task_context = std::make_unique<probe::AsyncTaskContext>();
  async_task_context->Schedule(execution_context, TaskNameForInstrumentation());
  execution_context->GetTaskRunner(TaskType::kFileReading)
      ->PostTask(
          FROM_HERE,
          blink::BindOnce(&RunCallback, WrapWeakPersistent(execution_context),
                          std::move(task), std::move(async_task_context)));
}

void DOMFileSystem::Trace(Visitor* visitor) const {
  visitor->Trace(root_entry_);
  DOMFileSystemBase::Trace(visitor);
  ExecutionContextClient::Trace(visitor);
}

}  // namespace blink