// Copyright 2022 The Cobalt Authors. All Rights Reserved.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
//     http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.

#include "cobalt/worker/service_worker_jobs.h"

#include <list>
#include <map>
#include <memory>
#include <queue>
#include <string>
#include <utility>

#include "base/bind.h"
#include "base/logging.h"
#include "base/message_loop/message_loop.h"
#include "base/synchronization/lock.h"
#include "base/trace_event/trace_event.h"
#include "cobalt/base/tokens.h"
#include "cobalt/loader/script_loader_factory.h"
#include "cobalt/network/network_module.h"
#include "cobalt/script/promise.h"
#include "cobalt/script/script_exception.h"
#include "cobalt/script/script_value.h"
#include "cobalt/web/context.h"
#include "cobalt/web/dom_exception.h"
#include "cobalt/web/environment_settings.h"
#include "cobalt/web/event.h"
#include "cobalt/worker/service_worker.h"
#include "cobalt/worker/service_worker_registration.h"
#include "cobalt/worker/service_worker_registration_object.h"
#include "cobalt/worker/service_worker_update_via_cache.h"
#include "cobalt/worker/worker_type.h"
#include "net/base/url_util.h"
#include "starboard/atomic.h"
#include "url/gurl.h"
#include "url/origin.h"

namespace cobalt {
namespace worker {

namespace {
bool PathContainsEscapedSlash(const GURL& url) {
  const std::string path = url.path();
  return (path.find("%2f") != std::string::npos ||
          path.find("%2F") != std::string::npos ||
          path.find("%5c") != std::string::npos ||
          path.find("%5C") != std::string::npos);
}

bool IsOriginPotentiallyTrustworthy(const GURL& url) {
  // Algorithm for potentially trustworthy origin:
  //   https://w3c.github.io/webappsec-secure-contexts/#potentially-trustworthy-origin

  const url::Origin origin(url::Origin::Create(url));
  // 1. If origin is an opaque origin, return "Not Trustworthy".
  if (origin.unique()) return false;

  // 2. Assert: origin is a tuple origin.
  DCHECK(!origin.unique());
  DCHECK(url.is_valid());

  // 3. If origin’s scheme is either "https" or "wss", return "Potentially
  // Trustworthy".
  if (url.SchemeIsCryptographic()) return true;

  // 4. If origin’s host matches one of the CIDR notations 127.0.0.0/8 or
  // ::1/128 [RFC4632], return "Potentially Trustworthy".
  if (net::IsLocalhost(url)) return true;

  // 5. If the user agent conforms to the name resolution rules in
  // [let-localhost-be-localhost] and one of the following is true:
  //    origin’s host is "localhost" or "localhost."
  //    origin’s host ends with ".localhost" or ".localhost."
  // then return "Potentially Trustworthy".
  // Covered by implementation of step 4.

  // 6. If origin’s scheme is "file", return "Potentially Trustworthy".
  if (url.SchemeIsFile()) return true;

  // 7. If origin’s scheme component is one which the user agent considers to be
  // authenticated, return "Potentially Trustworthy".
  if (url.SchemeIs("h5vcc-embedded")) return true;

  // 8. If origin has been configured as a trustworthy origin, return
  // "Potentially Trustworthy".

  // 9. Return "Not Trustworthy".
  return false;
}

bool PermitAnyURL(const GURL&, bool) { return true; }
}  // namespace

ServiceWorkerJobs::ServiceWorkerJobs(network::NetworkModule* network_module,
                                     base::MessageLoop* message_loop)
    : network_module_(network_module), message_loop_(message_loop) {
  fetcher_factory_.reset(new loader::FetcherFactory(network_module));
  DCHECK(fetcher_factory_);

  script_loader_factory_.reset(new loader::ScriptLoaderFactory(
      "ServiceWorkerJobs", fetcher_factory_.get()));
  DCHECK(script_loader_factory_);
}

ServiceWorkerJobs::~ServiceWorkerJobs() {
  DCHECK_EQ(message_loop(), base::MessageLoop::current());
  if (!web_context_registrations_.empty()) {
    DLOG(INFO) << "Waiting for web context registrations to be cleared. "
               << web_context_registrations_.size();
    // Wait for web context registrations to be cleared.
    web_context_registrations_cleared_.Wait();
  }
}

void ServiceWorkerJobs::StartRegister(
    const base::Optional<GURL>& maybe_scope_url,
    const GURL& script_url_with_fragment,
    std::unique_ptr<script::ValuePromiseWrappable::Reference> promise_reference,
    web::EnvironmentSettings* client, const WorkerType& type,
    const ServiceWorkerUpdateViaCache& update_via_cache) {
  TRACE_EVENT0("cobalt::worker", "ServiceWorkerJobs::StartRegister()");
  DCHECK_NE(message_loop(), base::MessageLoop::current());
  DCHECK_EQ(client->context()->message_loop(), base::MessageLoop::current());
  // Algorithm for Start Register:
  //   https://w3c.github.io/ServiceWorker/#start-register-algorithm
  // 1. If scriptURL is failure, reject promise with a TypeError and abort these
  // steps.
  if (script_url_with_fragment.is_empty()) {
    promise_reference->value().Reject(script::kTypeError);
    return;
  }

  // 2. Set scriptURL’s fragment to null.
  url::Replacements<char> replacements;
  replacements.ClearRef();
  GURL script_url = script_url_with_fragment.ReplaceComponents(replacements);
  DCHECK(!script_url.has_ref() || script_url.ref().empty());
  DCHECK(!script_url.is_empty());

  // 3. If scriptURL’s scheme is not one of "http" and "https", reject promise
  // with a TypeError and abort these steps.
  if (!script_url.SchemeIsHTTPOrHTTPS()) {
    promise_reference->value().Reject(script::kTypeError);
    return;
  }

  // 4. If any of the strings in scriptURL’s path contains either ASCII
  // case-insensitive "%2f" or ASCII case-insensitive "%5c", reject promise with
  // a TypeError and abort these steps.
  if (PathContainsEscapedSlash(script_url)) {
    promise_reference->value().Reject(script::kTypeError);
    return;
  }

  // 5. If scopeURL is null, set scopeURL to the result of parsing the string
  // "./" with scriptURL.
  GURL scope_url = maybe_scope_url.value_or(script_url.Resolve("./"));

  // 6. If scopeURL is failure, reject promise with a TypeError and abort these
  // steps.
  if (scope_url.is_empty()) {
    promise_reference->value().Reject(script::kTypeError);
    return;
  }

  // 7. Set scopeURL’s fragment to null.
  scope_url = scope_url.ReplaceComponents(replacements);
  DCHECK(!scope_url.has_ref() || scope_url.ref().empty());
  DCHECK(!scope_url.is_empty());

  // 8. If scopeURL’s scheme is not one of "http" and "https", reject promise
  // with a TypeError and abort these steps.
  if (!scope_url.SchemeIsHTTPOrHTTPS()) {
    promise_reference->value().Reject(script::kTypeError);
    return;
  }

  // 9. If any of the strings in scopeURL’s path contains either ASCII
  // case-insensitive "%2f" or ASCII case-insensitive "%5c", reject promise with
  // a TypeError and abort these steps.
  if (PathContainsEscapedSlash(scope_url)) {
    promise_reference->value().Reject(script::kTypeError);
    return;
  }

  // 10. Let storage key be the result of running obtain a storage key given
  // client.
  url::Origin storage_key = url::Origin::Create(client->creation_url());

  // 11. Let job be the result of running Create Job with register, storage key,
  // scopeURL, scriptURL, promise, and client.
  std::unique_ptr<Job> job =
      CreateJob(kRegister, storage_key, scope_url, script_url,
                JobPromiseType::Create(std::move(promise_reference)), client);
  DCHECK(!promise_reference);

  // 12. Set job’s worker type to workerType.
  // Cobalt only supports 'classic' worker type.

  // 13. Set job’s update via cache mode to updateViaCache.
  job->update_via_cache = update_via_cache;

  // 14. Set job’s referrer to referrer.
  // This is the same value as set in CreateJob().

  // 15. Invoke Schedule Job with job.
  message_loop()->task_runner()->PostTask(
      FROM_HERE, base::BindOnce(&ServiceWorkerJobs::ScheduleJob,
                                base::Unretained(this), std::move(job)));
  DCHECK(!job.get());
}

void ServiceWorkerJobs::PromiseErrorData::Reject(
    std::unique_ptr<JobPromiseType> promise) const {
  if (message_type_ != script::kNoError) {
    promise->Reject(GetSimpleExceptionType(message_type_));
  } else {
    promise->Reject(new web::DOMException(exception_code_, message_));
  }
}

std::unique_ptr<ServiceWorkerJobs::Job> ServiceWorkerJobs::CreateJob(
    JobType type, const url::Origin& storage_key, const GURL& scope_url,
    const GURL& script_url, std::unique_ptr<JobPromiseType> promise,
    web::EnvironmentSettings* client) {
  TRACE_EVENT0("cobalt::worker", "ServiceWorkerJobs::CreateJob()");
  // Algorithm for Create Job:
  //   https://w3c.github.io/ServiceWorker/#create-job
  // 1. Let job be a new job.
  // 2. Set job’s job type to jobType.
  // 3. Set job’s storage key to storage key.
  // 4. Set job’s scope url to scopeURL.
  // 5. Set job’s script url to scriptURL.
  // 6. Set job’s job promise to promise.
  // 7. Set job’s client to client.
  std::unique_ptr<Job> job(new Job(kRegister, storage_key, scope_url,
                                   script_url, client, std::move(promise)));
  // 8. If client is not null, set job’s referrer to client’s creation URL.
  if (client) {
    job->referrer = client->creation_url();
  }
  // 9. Return job.
  return job;
}

void ServiceWorkerJobs::ScheduleJob(std::unique_ptr<Job> job) {
  TRACE_EVENT0("cobalt::worker", "ServiceWorkerJobs::ScheduleJob()");
  DCHECK_EQ(message_loop(), base::MessageLoop::current());
  DCHECK(job);
  // Algorithm for Schedule Job:
  //   https://w3c.github.io/ServiceWorker/#schedule-job
  // 1. Let jobQueue be null.

  // 2. Let jobScope be job’s scope url, serialized.
  std::string job_scope = job->scope_url.spec();

  // 3. If scope to job queue map[jobScope] does not exist, set scope to job
  // queue map[jobScope] to a new job queue.
  if (job_queue_map_.find(job_scope) == job_queue_map_.end()) {
    auto insertion = job_queue_map_.emplace(
        job_scope, std::unique_ptr<JobQueue>(new JobQueue()));
    DCHECK(insertion.second);
  }

  // 4. Set jobQueue to scope to job queue map[jobScope].
  DCHECK(job_queue_map_.find(job_scope) != job_queue_map_.end());
  JobQueue* job_queue = job_queue_map_.find(job_scope)->second.get();

  // 5. If jobQueue is empty, then:
  if (job_queue->empty()) {
    // 5.1. Set job’s containing job queue to jobQueue, and enqueue job to
    // jobQueue.
    job->containing_job_queue = job_queue;
    job_queue->Enqueue(std::move(job));

    // 5.2. Invoke Run Job with jobQueue.
    RunJob(job_queue);

  } else {
    // 6. Else:
    // 6.1. Let lastJob be the element at the back of jobQueue.
    {
      auto last_item = job_queue->LastItem();
      Job* last_job = last_item.first;

      // 6.2. If job is equivalent to lastJob and lastJob’s job promise has not
      // settled, append job to lastJob’s list of equivalent jobs.
      DCHECK(last_job);
      base::AutoLock lock(last_job->equivalent_jobs_promise_mutex);
      if (EquivalentJobs(job.get(), last_job) && last_job->promise &&
          last_job->promise->State() == script::PromiseState::kPending) {
        last_job->equivalent_jobs.push_back(std::move(job));
        return;
      }
    }

    // 6.3. Else, set job’s containing job queue to jobQueue, and enqueue job to
    // jobQueue.
    job->containing_job_queue = job_queue;
    job_queue->Enqueue(std::move(job));
  }
  DCHECK(!job);
}

bool ServiceWorkerJobs::EquivalentJobs(Job* one, Job* two) {
  // Algorithm for Two jobs are equivalent:
  //   https://w3c.github.io/ServiceWorker/#dfn-job-equivalent
  DCHECK(one);
  DCHECK(two);
  if (!one || !two) {
    return false;
  }

  // Two jobs are equivalent when their job type is the same and:
  if (one->type != two->type) {
    return false;
  }

  // For register and update jobs, their scope url, script url, worker type, and
  // update via cache mode are the same.
  if ((one->type == kRegister || one->type == kUpdate) &&
      (one->scope_url == two->scope_url) &&
      (one->script_url == two->script_url) &&
      (one->update_via_cache == two->update_via_cache)) {
    return true;
  }

  // For unregister jobs, their scope url is the same.
  return (one->type == kUnregister) && (one->scope_url == two->scope_url);
}

void ServiceWorkerJobs::RunJob(JobQueue* job_queue) {
  TRACE_EVENT0("cobalt::worker", "ServiceWorkerJobs::RunJob()");
  DCHECK_EQ(message_loop(), base::MessageLoop::current());
  // Algorithm for Run Job:
  //   https://w3c.github.io/ServiceWorker/#run-job-algorithm

  // 1. Assert: jobQueue is not empty.
  DCHECK(job_queue && !job_queue->empty());
  if (!job_queue || job_queue->empty()) {
    return;
  }

  // 2. Queue a task to run these steps:
  message_loop()->task_runner()->PostTask(
      FROM_HERE, base::BindOnce(&ServiceWorkerJobs::RunJobTask,
                                base::Unretained(this), job_queue));
}

void ServiceWorkerJobs::RunJobTask(JobQueue* job_queue) {
  TRACE_EVENT0("cobalt::worker", "ServiceWorkerJobs::RunJobTask()");
  DCHECK_EQ(message_loop(), base::MessageLoop::current());
  // Task for "Run Job" to run in the service worker thread.
  //   https://w3c.github.io/ServiceWorker/#run-job-algorithm
  DCHECK(job_queue);
  if (!job_queue) return;
  DCHECK(!job_queue->empty());

  // 2.1 Let job be the first item in jobQueue.
  Job* job = job_queue->FirstItem();

  DCHECK(job);
  switch (job->type) {
    // 2.2 If job’s job type is register, run Register with job in parallel.
    case kRegister:
      Register(job);
      break;

    // 2.3 Else if job’s job type is update, run Update with job in parallel.
    case kUpdate:
      Update(job);
      break;

    // 2.4 Else if job’s job type is unregister, run Unregister with job in
    // parallel.
    case kUnregister:
      Unregister(job);
      break;
    default:
      NOTREACHED();
  }
}

void ServiceWorkerJobs::Register(Job* job) {
  TRACE_EVENT0("cobalt::worker", "ServiceWorkerJobs::Register()");
  DCHECK_EQ(message_loop(), base::MessageLoop::current());
  DCHECK(job);
  // Algorithm for Register:
  //   https://w3c.github.io/ServiceWorker/#register-algorithm

  // 1. If the result of running potentially trustworthy origin with the origin
  // of job’s script url as the argument is Not Trusted, then:
  if (!IsOriginPotentiallyTrustworthy(job->script_url)) {
    // 1.1. Invoke Reject Job Promise with job and "SecurityError" DOMException.
    RejectJobPromise(
        job, PromiseErrorData(
                 web::DOMException::kSecurityErr,
                 "Service Worker Register failed: Script URL is Not Trusted."));
    // 1.2. Invoke Finish Job with job and abort these steps.
    FinishJob(job);
    return;
  }

  // 2. If job’s script url's origin and job’s referrer's origin are not same
  // origin, then:
  const url::Origin job_script_origin(url::Origin::Create(job->script_url));
  const url::Origin job_referrer_origin(url::Origin::Create(job->referrer));
  if (!job_script_origin.IsSameOriginWith(job_referrer_origin)) {
    // 2.1. Invoke Reject Job Promise with job and "SecurityError" DOMException.
    RejectJobPromise(
        job, PromiseErrorData(
                 web::DOMException::kSecurityErr,
                 "Service Worker Register failed: Script URL and referrer "
                 "origin are not the same."));
    // 2.2. Invoke Finish Job with job and abort these steps.
    FinishJob(job);
    return;
  }

  // 3. If job’s scope url's origin and job’s referrer's origin are not same
  // origin, then:
  const url::Origin job_scope_origin(url::Origin::Create(job->scope_url));
  if (!job_scope_origin.IsSameOriginWith(job_referrer_origin)) {
    // 3.1. Invoke Reject Job Promise with job and "SecurityError" DOMException.
    RejectJobPromise(
        job, PromiseErrorData(
                 web::DOMException::kSecurityErr,
                 "Service Worker Register failed: Scope URL and referrer "
                 "origin are not the same."));

    // 3.2. Invoke Finish Job with job and abort these steps.
    FinishJob(job);
    return;
  }

  // 4. Let registration be the result of running Get Registration given job’s
  // storage key and job’s scope url.
  ServiceWorkerRegistrationObject* registration =
      scope_to_registration_map_.GetRegistration(job->storage_key,
                                                 job->scope_url);

  // 5. If registration is not null, then:
  if (registration) {
    // 5.1 Let newestWorker be the result of running the Get Newest Worker
    // algorithm passing registration as the argument.
    ServiceWorkerObject* newest_worker = registration->GetNewestWorker();

    // 5.2 If newestWorker is not null, job’s script url equals newestWorker’s
    // script url, job’s worker type equals newestWorker’s type, and job’s
    // update via cache mode's value equals registration’s update via cache
    // mode, then:
    if (newest_worker && job->script_url == newest_worker->script_url()) {
      // 5.2.1 Invoke Resolve Job Promise with job and registration.
      ResolveJobPromise(job, registration);

      // 5.2.2 Invoke Finish Job with job and abort these steps.
      FinishJob(job);
      return;
    }
  } else {
    // 6. Else:

    // 6.1 Invoke Set Registration algorithm with job’s storage key, job’s scope
    // url, and job’s update via cache mode.
    registration = scope_to_registration_map_.SetRegistration(
        job->storage_key, job->scope_url, job->update_via_cache);
  }

  // 7. Invoke Update algorithm passing job as the argument.
  Update(job);
}

void ServiceWorkerJobs::Update(Job* job) {
  TRACE_EVENT0("cobalt::worker", "ServiceWorkerJobs::Update()");
  DCHECK_EQ(message_loop(), base::MessageLoop::current());
  DCHECK(job);
  // Algorithm for Update:
  //   https://w3c.github.io/ServiceWorker/#update-algorithm

  // 1. Let registration be the result of running Get Registration given job’s
  //    storage key and job’s scope url.
  ServiceWorkerRegistrationObject* registration =
      scope_to_registration_map_.GetRegistration(job->storage_key,
                                                 job->scope_url);

  // 2. If registration is null, then:
  if (!registration) {
    // 2.1. Invoke Reject Job Promise with job and TypeError.
    RejectJobPromise(job, PromiseErrorData(script::kSimpleTypeError));

    // 2.2. Invoke Finish Job with job and abort these steps.
    FinishJob(job);
    return;
  }
  // 3. Let newestWorker be the result of running Get Newest Worker algorithm
  //    passing registration as the argument.
  ServiceWorkerObject* newest_worker = registration->GetNewestWorker();

  // 4. If job’s job type is update, and newestWorker is not null and its script
  //    url does not equal job’s script url, then:
  if ((job->type == kUpdate) && newest_worker &&
      (newest_worker->script_url() != job->script_url)) {
    // 4.1 Invoke Reject Job Promise with job and TypeError.
    RejectJobPromise(job, PromiseErrorData(script::kSimpleTypeError));

    // 4.2 Invoke Finish Job with job and abort these steps.
    FinishJob(job);
    return;
  }

  auto state(
      base::MakeRefCounted<UpdateJobState>(job, registration, newest_worker));

  // 5. Let referrerPolicy be the empty string.
  // 6. Let hasUpdatedResources be false.
  state->has_updated_resources = false;
  // 7. Let updatedResourceMap be an ordered map where the keys are URLs and the
  //    values are responses.
  // That is located in job->updated_resource_map.

  // 8. Switching on job’s worker type, run these substeps with the following
  //    options:
  //    - "classic"
  //        Fetch a classic worker script given job’s serialized script url,
  //        job’s client, "serviceworker", and the to-be-created environment
  //        settings object for this service worker.
  //    - "module"
  //        Fetch a module worker script graph given job’s serialized script
  //        url, job’s client, "serviceworker", "omit", and the to-be-created
  //        environment settings object for this service worker.
  // To perform the fetch given request, run the following steps:
  //   8.1.  Append `Service-Worker`/`script` to request’s header list.
  //   8.2.  Set request’s cache mode to "no-cache" if any of the following are
  //         true:
  //          - registration’s update via cache mode is not "all".
  //          - job’s force bypass cache flag is set.
  //          - newestWorker is not null and registration is stale.
  //   8.3.  Set request’s service-workers mode to "none".
  //   8.4.  If the is top-level flag is unset, then return the result of
  //         fetching request.
  //   8.5.  Set request’s redirect mode to "error".
  //   8.6.  Fetch request, and asynchronously wait to run the remaining steps
  //         as part of fetch’s process response for the response response.
  //   8.7.  Extract a MIME type from the response’s header list. If this MIME
  //         type (ignoring parameters) is not a JavaScript MIME type, then:
  //   8.7.1. Invoke Reject Job Promise with job and "SecurityError"
  //          DOMException.
  //   8.7.2. Asynchronously complete these steps with a network error.
  //   8.8.  Let serviceWorkerAllowed be the result of extracting header list
  //         values given `Service-Worker-Allowed` and response’s header list.
  //   8.9.  Set policyContainer to the result of creating a policy container
  //         from a fetch response given response.
  //   8.10. If serviceWorkerAllowed is failure, then:
  //   8.10.1  Asynchronously complete these steps with a network error.
  //   8.11. Let scopeURL be registration’s scope url.
  //   8.12. Let maxScopeString be null.
  //   8.13. If serviceWorkerAllowed is null, then:
  //   8.13.1. Let resolvedScope be the result of parsing "./" using job’s
  //           script url as the base URL.
  //   8.13.2. Set maxScopeString to "/", followed by the strings in
  //           resolvedScope’s path (including empty strings), separated from
  //           each other by "/".
  //   8.14. Else:
  //   8.14.1. Let maxScope be the result of parsing serviceWorkerAllowed using
  //           job’s script url as the base URL.
  //   8.14.2. If maxScope’s origin is job’s script url's origin, then:
  //   8.14.2.1. Set maxScopeString to "/", followed by the strings in
  //             maxScope’s path (including empty strings), separated from each
  //             other by "/".
  //   8.15. Let scopeString be "/", followed by the strings in scopeURL’s path
  //         (including empty strings), separated from each other by "/".
  //   8.16. If maxScopeString is null or scopeString does not start with
  //         maxScopeString, then:
  //   8.16.1. Invoke Reject Job Promise with job and "SecurityError"
  //           DOMException.
  //   8.16.2. Asynchronously complete these steps with a network error.

  // TODO(b/225037465): Implement CSP check.
  csp::SecurityCallback csp_callback = base::Bind(&PermitAnyURL);
  loader::Origin origin = loader::Origin(job->script_url.GetOrigin());
  job->loader = script_loader_factory_->CreateScriptLoader(
      job->script_url, origin, csp_callback,
      base::Bind(&ServiceWorkerJobs::UpdateOnContentProduced,
                 base::Unretained(this), state),
      base::Bind(&ServiceWorkerJobs::UpdateOnLoadingComplete,
                 base::Unretained(this), state));
}

void ServiceWorkerJobs::UpdateOnContentProduced(
    scoped_refptr<UpdateJobState> state, const loader::Origin& last_url_origin,
    std::unique_ptr<std::string> content) {
  TRACE_EVENT0("cobalt::worker",
               "ServiceWorkerJobs::UpdateOnContentProduced()");
  // Note: There seems to be missing handling of network errors here.
  //   8.17. Let url be request’s url.
  //   8.18. Set updatedResourceMap[url] to response.
  state->updated_resource_map.insert(
      std::make_pair(state->job->script_url, std::move(content)));
  //   8.19. If response’s cache state is not "local", set registration’s last
  //         update check time to the current time.
  //   8.20. Set hasUpdatedResources to true if any of the following are true:
  //          - newestWorker is null.
  //          - newestWorker’s script url is not url or newestWorker’s type is
  //            not job’s worker type.
  // Note: Cobalt only supports 'classic' worker type.
  //          - newestWorker’s script resource map[url]'s body is not
  //            byte-for-byte identical with response’s body.
  if (state->newest_worker == nullptr) {
    state->has_updated_resources = true;
  } else {
    if (state->newest_worker->script_url() != state->job->script_url) {
      state->has_updated_resources = true;
    } else {
      std::string* script_resource =
          state->newest_worker->LookupScriptResource(state->job->script_url);
      if (script_resource && content && (*script_resource != *content)) {
        state->has_updated_resources = true;
      }
    }
  }

  // TODO(b/228900516): The logic below is needed for importScripts().
  //   8.21. If hasUpdatedResources is false and newestWorker’s classic
  //         scripts imported flag is set, then:
  //   8.21.1. For each importUrl → storedResponse of newestWorker’s script
  //           resource map:
  //   8.21.1.1. If importUrl is url, then continue.
  //   8.21.1.2. Let importRequest be a new request whose url is importUrl,
  //             client is job’s client, destination is "script", parser
  //             metadata is "not parser-inserted", synchronous flag is set,
  //             and whose use-URL-credentials flag is set.
  //   8.21.1.3. Set importRequest’s cache mode to "no-cache" if any of the
  //             following are true:
  //               - registration’s update via cache mode is "none".
  //               - job’s force bypass cache flag is set.
  //               - registration is stale.
  //   8.21.1.4. Let fetchedResponse be the result of fetching importRequest.
  //   8.21.1.5. Set updatedResourceMap[importRequest’s url] to
  //             fetchedResponse.
  //   8.21.1.6. Set fetchedResponse to fetchedResponse’s unsafe response.
  //   8.21.1.7. If fetchedResponse’s cache state is not
  //             "local", set registration’s last update check time to the
  //             current time.
  //   8.21.1.8. If fetchedResponse is a bad import script response, continue.
  //   8.21.1.9. If fetchedResponse’s body is not byte-for-byte identical with
  //             storedResponse’s unsafe response's body, set
  //             hasUpdatedResources to true.
  //   8.22. Asynchronously complete these steps with response.
}

void ServiceWorkerJobs::UpdateOnLoadingComplete(
    scoped_refptr<UpdateJobState> state,
    const base::Optional<std::string>& error) {
  TRACE_EVENT0("cobalt::worker",
               "ServiceWorkerJobs::UpdateOnLoadingComplete()");
  // TODO: This shouldn't run until the load for each script from the script
  // resource map completes (step 8.22).

  // When the algorithm asynchronously completes, continue the rest of these
  // steps, with script being the asynchronous completion value.
  auto entry = state->updated_resource_map.find(state->job->script_url);
  auto* script = entry != state->updated_resource_map.end()
                     ? entry->second.get()
                     : nullptr;
  // 9. If script is null or Is Async Module with script’s record, script’s
  //    base URL, and {} it true, then:
  if (script == nullptr) {
    // 9.1. Invoke Reject Job Promise with job and TypeError.
    RejectJobPromise(state->job, PromiseErrorData(script::kSimpleTypeError));

    // 9.2. If newestWorker is null, then remove registration
    //      map[(registration’s storage key, serialized scopeURL)].
    if (state->newest_worker == nullptr) {
      scope_to_registration_map_.RemoveRegistration(state->job->storage_key,
                                                    state->job->scope_url);
    }
    // 9.3. Invoke Finish Job with job and abort these steps.
    FinishJob(state->job);
    return;
  }

  // 10. If hasUpdatedResources is false, then:
  if (!state->has_updated_resources) {
    // 10.1. Set registration’s update via cache mode to job’s update via cache
    //       mode.
    state->registration->set_update_via_cache_mode(
        state->job->update_via_cache);

    // 10.2. Invoke Resolve Job Promise with job and registration.
    ResolveJobPromise(state->job, state->registration);

    // 10.3. Invoke Finish Job with job and abort these steps.
    FinishJob(state->job);
    return;
  }

  // 11. Let worker be a new service worker.
  ServiceWorkerObject::Options options(
      "ServiceWorker", state->job->client->context()->network_module());
  std::unique_ptr<ServiceWorkerObject> worker(new ServiceWorkerObject(options));
  // 12. Set worker’s script url to job’s script url, worker’s script
  //     resource to script, worker’s type to job’s worker type, and worker’s
  //     script resource map to updatedResourceMap.
  // -> The worker's script resource is set in the resource map at step 8.18.
  worker->set_script_url(state->job->script_url);
  worker->set_script_resource_map(std::move(state->updated_resource_map));
  // 13. Append url to worker’s set of used scripts.
  // -> The script resource map contains the used scripts.
  // 14. Set worker’s script resource’s policy container to policyContainer.
  // 15. Let forceBypassCache be true if job’s force bypass cache flag is
  //     set, and false otherwise.
  bool force_bypass_cache = state->job->force_bypass_cache_flag;
  // 16. Let runResult be the result of running the Run Service Worker
  //     algorithm with worker and forceBypassCache.
  auto* run_result = RunServiceWorker(worker.get(), force_bypass_cache);
  // 17. If runResult is failure or an abrupt completion, then:
  if (!run_result) {
    // 17.1. Invoke Reject Job Promise with job and TypeError.
    RejectJobPromise(state->job, PromiseErrorData(script::kSimpleTypeError));
    // 17.2. If newestWorker is null, then remove registration
    //       map[(registration’s storage key, serialized scopeURL)].
    if (state->newest_worker == nullptr) {
      scope_to_registration_map_.RemoveRegistration(state->job->storage_key,
                                                    state->job->scope_url);
    }
    // 17.3. Invoke Finish Job with job.
    FinishJob(state->job);
  } else {
    // 18. Else, invoke Install algorithm with job, worker, and registration
    //     as its arguments.
    Install(state->job, worker.get(), state->registration);
  }
}

std::string* ServiceWorkerJobs::RunServiceWorker(ServiceWorkerObject* worker,
                                                 bool force_bypass_cache) {
  TRACE_EVENT0("cobalt::worker", "ServiceWorkerJobs::RunServiceWorker()");

  DCHECK_EQ(message_loop(), base::MessageLoop::current());
  DCHECK(worker);
  // return worker->Run(force_bypass_cache);
  // Algorithm for "Run Service Worker"
  //   https://w3c.github.io/ServiceWorker/#run-service-worker-algorithm

  // 1. Let unsafeCreationTime be the unsafe shared current time.
  auto unsafe_creation_time = base::TimeTicks::Now();
  // 2. If serviceWorker is running, then return serviceWorker’s start status.
  if (worker->is_running()) {
    return worker->start_status();
  }
  // 3. If serviceWorker’s state is "redundant", then return failure.
  if (worker->state() == kServiceWorkerStateRedundant) {
    return nullptr;
  }
  // 4. Assert: serviceWorker’s start status is null.
  DCHECK(worker->start_status() == nullptr);
  // 5. Let script be serviceWorker’s script resource.
  std::string* script = worker->LookupScriptResource();
  // 6. Assert: script is not null.
  DCHECK(script != nullptr);
  // 7. Let startFailed be false.
  worker->store_start_failed(false);
  // 8. Let agent be the result of obtaining a service worker agent, and run the
  //    following steps in that context:
  // 9. Wait for serviceWorker to be running, or for startFailed to be true.
  worker->ObtainWebAgentAndWaitUntilDone();
  // 10. If startFailed is true, then return failure.
  if (worker->load_start_failed()) {
    return nullptr;
  }
  // 11. Return serviceWorker’s start status.
  return worker->start_status();
}

void ServiceWorkerJobs::Install(Job* job, ServiceWorkerObject* worker,
                                ServiceWorkerRegistrationObject* registration) {
  TRACE_EVENT0("cobalt::worker", "ServiceWorkerJobs::Install()");
  DCHECK_EQ(message_loop(), base::MessageLoop::current());
  // Algorithm for Install:
  //   https://w3c.github.io/ServiceWorker/#installation-algorithm

  // 1. Let installFailed be false.
  starboard::atomic_bool install_failed(false);

  // 2. Let newestWorker be the result of running Get Newest Worker algorithm
  //    passing registration as its argument.
  ServiceWorkerObject* newest_worker = registration->GetNewestWorker();

  // 3. Set registration’s update via cache mode to job’s update via cache mode.
  registration->set_update_via_cache_mode(job->update_via_cache);

  // 4. Run the Update Registration State algorithm passing registration,
  //    "installing" and worker as the arguments.
  UpdateRegistrationState(registration, kInstalling, worker);

  // 5. Run the Update Worker State algorithm passing registration’s installing
  //    worker and "installing" as the arguments.
  UpdateWorkerState(registration->installing_worker(),
                    kServiceWorkerStateInstalling);
  // 6. Assert: job’s job promise is not null.
  DCHECK(job->promise.get() != nullptr);
  // 7. Invoke Resolve Job Promise with job and registration.
  ResolveJobPromise(job, registration);
  // 8. Let settingsObjects be all environment settings objects whose origin is
  //    registration’s scope url's origin.
  auto registration_origin = registration->scope_url().GetOrigin();
  // 9. For each settingsObject of settingsObjects...
  for (auto& context : web_context_registrations_) {
    if (context->environment_settings()->GetOrigin() == registration_origin) {
      // 9. ... queue a task on settingsObject’s responsible event loop in the
      //    DOM manipulation task source to run the following steps:
      context->message_loop()->task_runner()->PostTask(
          FROM_HERE,
          base::BindOnce(
              [](web::Context* context,
                 ServiceWorkerRegistrationObject* registration) {
                // 9.1. Let registrationObjects be every
                // ServiceWorkerRegistration
                //      object in settingsObject’s realm, whose service worker
                //      registration is registration.

                // There is at most one per web context, stored in the service
                // worker registration object map of the web context.

                // 9.2. For each registrationObject of registrationObjects, fire
                // an
                //      event on registrationObject named updatefound.
                auto registration_object =
                    context->LookupServiceWorkerRegistration(registration);
                if (registration_object) {
                  context->message_loop()->task_runner()->PostTask(
                      FROM_HERE,
                      base::BindOnce(
                          [](scoped_refptr<worker::ServiceWorkerRegistration>
                                 registration_object) {
                            registration_object->DispatchEvent(
                                new web::Event(base::Tokens::updatefound()));
                          },
                          registration_object));
                }
              },
              context, registration));
    }
  }
  // 10. Let installingWorker be registration’s installing worker.
  ServiceWorkerObject* installing_worker = registration->installing_worker();
  // 11. If the result of running the Should Skip Event algorithm with
  //     installingWorker and "install" is false, then:
  if (!ShouldSkipEvent(base::Tokens::install(), installing_worker)) {
    // 11.1. Let forceBypassCache be true if job’s force bypass cache flag is
    //       set, and false otherwise.
    bool force_bypass_cache = job->force_bypass_cache_flag;
    // 11.2. If the result of running the Run Service Worker algorithm with
    //       installingWorker and forceBypassCache is failure, then:
    auto* run_result = RunServiceWorker(installing_worker, force_bypass_cache);
    if (!run_result) {
      // 11.2.1. Set installFailed to true.
      install_failed.store(true);
      // 11.3. Else:
    } else {
      // 11.3.1. Queue a task task on installingWorker’s event loop using the
      //         DOM manipulation task source to run the following steps:
      installing_worker->web_agent()
          ->context()
          ->message_loop()
          ->task_runner()
          ->PostBlockingTask(
              FROM_HERE,
              base::Bind(
                  [](ServiceWorkerObject* installing_worker) {
                    // 11.3.1.1. Let e be the result of creating an event with
                    //           ExtendableEvent.
                    // TODO: implement this as ExtendableEvent.
                    // 11.3.1.2. Initialize e’s type attribute to install.
                    // 11.3.1.3. Dispatch e at installingWorker’s global object.
                    installing_worker->worker_global_scope()->DispatchEvent(
                        new web::Event(base::Tokens::install()));
                    // 11.3.1.4. WaitForAsynchronousExtensions: Run the
                    //           following substeps in parallel:
                    // 11.3.1.4.1. Wait until e is not active.
                    // 11.3.1.4.2. If e’s timed out flag is set, set
                    //             installFailed to true.
                    // 11.3.1.4.3. Let p be the result of getting a promise to
                    //             wait for all of e’s extend lifetime promises.
                    // 11.3.1.4.4. Upon rejection of p, set installFailed to
                    //             true.
                    //         If task is discarded, set installFailed to true.
                  },
                  installing_worker));
      // 11.3.2. Wait for task to have executed or been discarded.
      // Waiting is done inside PostBlockingTask above.
      // 11.3.3. Wait for the step labeled WaitForAsynchronousExtensions to
      //         complete.
      NOTIMPLEMENTED();
    }
  }
  // 12. If installFailed is true, then:
  if (install_failed.load()) {
    // 12.1. Run the Update Worker State algorithm passing registration’s
    //       installing worker and "redundant" as the arguments.
    UpdateWorkerState(registration->installing_worker(),
                      kServiceWorkerStateRedundant);
    // 12.2. Run the Update Registration State algorithm passing registration,
    //       "installing" and null as the arguments.
    UpdateRegistrationState(registration, kInstalling, nullptr);
    // 12.3. If newestWorker is null, then remove registration
    //       map[(registration’s storage key, serialized registration’s
    //       scope url)].
    if (newest_worker == nullptr) {
      scope_to_registration_map_.RemoveRegistration(registration->storage_key(),
                                                    registration->scope_url());
    }
    // 12.4. Invoke Finish Job with job and abort these steps.
    FinishJob(job);
    return;
  }
  // Note: The logic below is for scripts added with importScript().
  // 13. Let map be registration’s installing worker's script resource map.
  // 14. Let usedSet be registration’s installing worker's set of used scripts.
  // 15. For each url of map:
  // 15.1. If usedSet does not contain url, then remove map[url].
  // 16. If registration’s waiting worker is not null, then:
  if (registration->waiting_worker()) {
    // 16.1. Terminate registration’s waiting worker.
    TerminateServiceWorker(registration->waiting_worker());
    // 16.2. Run the Update Worker State algorithm passing registration’s
    //       waiting worker and "redundant" as the arguments.
    UpdateWorkerState(registration->waiting_worker(),
                      kServiceWorkerStateRedundant);
  }
  // 17. Run the Update Registration State algorithm passing registration,
  //     "waiting" and registration’s installing worker as the arguments.
  UpdateRegistrationState(registration, kWaiting,
                          registration->installing_worker());
  // 18. Run the Update Registration State algorithm passing registration,
  //     "installing" and null as the arguments.
  UpdateRegistrationState(registration, kInstalling, nullptr);
  // 19. Run the Update Worker State algorithm passing registration’s waiting
  //     worker and "installed" as the arguments.
  UpdateWorkerState(registration->waiting_worker(),
                    kServiceWorkerStateInstalled);
  // 20. Invoke Finish Job with job.
  FinishJob(job);
  // 21. Wait for all the tasks queued by Update Worker State invoked in this
  //     algorithm to have executed.
  // TODO: Wait for tasks.
  // 22. Invoke Try Activate with registration.
  TryActivate(registration);
}

void ServiceWorkerJobs::TryActivate(
    ServiceWorkerRegistrationObject* registration) {
  // Algorithm for Try Activate:
  //   https://w3c.github.io/ServiceWorker/#try-activate-algorithm
  NOTIMPLEMENTED();
}

void ServiceWorkerJobs::UpdateRegistrationState(
    ServiceWorkerRegistrationObject* registration, RegistrationState target,
    ServiceWorkerObject* source) {
  TRACE_EVENT0("cobalt::worker",
               "ServiceWorkerJobs::UpdateRegistrationState()");
  DCHECK(registration);
  // Algorithm for Update Registration State:
  //   https://w3c.github.io/ServiceWorker/#update-registration-state-algorithm

  // 1. Let registrationObjects be an array containing all the
  //    ServiceWorkerRegistration objects associated with registration.
  // This is implemented with a call to LookupServiceWorkerRegistration for each
  // registered web context.

  switch (target) {
    // 2. If target is "installing", then:
    case kInstalling: {
      // 2.1. Set registration’s installing worker to source.
      registration->set_installing_worker(source);
      // 2.2. For each registrationObject in registrationObjects:
      for (auto& context : web_context_registrations_) {
        // 2.2.1. Queue a task to...
        context->message_loop()->task_runner()->PostTask(
            FROM_HERE,
            base::BindOnce(
                [](web::Context* context,
                   ServiceWorkerRegistrationObject* registration) {
                  // 2.2.1. ... set the installing attribute of
                  //        registrationObject to null if registration’s
                  //        installing worker is null, or the result of getting
                  //        the service worker object that represents
                  //        registration’s installing worker in
                  //        registrationObject’s relevant settings object.
                  auto registration_object =
                      context->GetServiceWorkerRegistration(registration);
                  if (registration_object) {
                    registration_object->set_installing(
                        context->GetServiceWorker(
                            registration->installing_worker()));
                  }
                },
                context, registration));
      }
      break;
    }
    // 3. Else if target is "waiting", then:
    case kWaiting: {
      // 3.1. Set registration’s waiting worker to source.
      registration->set_waiting_worker(source);
      // 3.2. For each registrationObject in registrationObjects:
      for (auto& context : web_context_registrations_) {
        // 3.2.1. Queue a task to...
        context->message_loop()->task_runner()->PostTask(
            FROM_HERE,
            base::BindOnce(
                [](web::Context* context,
                   ServiceWorkerRegistrationObject* registration) {
                  // 3.2.1. ... set the waiting attribute of registrationObject
                  //        to null if registration’s waiting worker is null, or
                  //        the result of getting the service worker object that
                  //        represents registration’s waiting worker in
                  //        registrationObject’s relevant settings object.
                  auto registration_object =
                      context->LookupServiceWorkerRegistration(registration);
                  if (registration_object) {
                    registration_object->set_waiting(context->GetServiceWorker(
                        registration->waiting_worker()));
                  }
                },
                context, registration));
      }
      break;
    }
    // 4. Else if target is "active", then:
    case kActive: {
      // 4.1. Set registration’s active worker to source.
      registration->set_active_worker(source);
      // 4.2. For each registrationObject in registrationObjects:
      for (auto& context : web_context_registrations_) {
        // 4.2.1. Queue a task to...
        context->message_loop()->task_runner()->PostTask(
            FROM_HERE,
            base::BindOnce(
                [](web::Context* context,
                   ServiceWorkerRegistrationObject* registration) {
                  // 4.2.1. ... set the active attribute of registrationObject
                  //        to null if registration’s active worker is null, or
                  //        the result of getting the service worker object that
                  //        represents registration’s active worker in
                  //        registrationObject’s relevant settings object.
                  auto registration_object =
                      context->LookupServiceWorkerRegistration(registration);
                  if (registration_object) {
                    registration_object->set_active(context->GetServiceWorker(
                        registration->active_worker()));
                  }
                },
                context, registration));
      }
      break;
    }
    default:
      NOTREACHED();
  }
}

void ServiceWorkerJobs::UpdateWorkerState(ServiceWorkerObject* worker,
                                          ServiceWorkerState state) {
  TRACE_EVENT0("cobalt::worker", "ServiceWorkerJobs::UpdateWorkerState()");
  DCHECK(worker);
  if (!worker) {
    return;
  }
  // Algorithm for Update Worker State:
  //   https://w3c.github.io/ServiceWorker/#update-state-algorithm
  // 1. Assert: state is not "parsed".
  DCHECK_NE(kServiceWorkerStateParsed, state);
  // 2. Set worker's state to state.
  worker->set_state(state);

  auto worker_origin = worker->script_url().GetOrigin();
  // 3. Let settingsObjects be all environment settings objects whose origin is
  //    worker's script url's origin.
  // 4. For each settingsObject of settingsObjects...
  for (auto& context : web_context_registrations_) {
    if (context->environment_settings()->GetOrigin() == worker_origin) {
      // 4. ... queue a task on
      //    settingsObject's responsible event loop in the DOM manipulation task
      //    source to run the following steps:
      context->message_loop()->task_runner()->PostTask(
          FROM_HERE,
          base::BindOnce(
              [](web::Context* context, ServiceWorkerObject* worker,
                 ServiceWorkerState state) {
                DCHECK_EQ(context->message_loop(),
                          base::MessageLoop::current());
                // 4.1. Let objectMap be settingsObject's service worker object
                //      map.
                // 4.2. If objectMap[worker] does not exist, then abort these
                //      steps.
                // 4.3. Let  workerObj be objectMap[worker].
                auto worker_obj = context->LookupServiceWorker(worker);
                if (worker_obj) {
                  // 4.4. Set workerObj's state to state.
                  worker_obj->set_state(state);
                  // 4.5. Fire an event named statechange at workerObj.
                  context->message_loop()->task_runner()->PostTask(
                      FROM_HERE,
                      base::BindOnce(
                          [](scoped_refptr<worker::ServiceWorker> worker_obj) {
                            worker_obj->DispatchEvent(
                                new web::Event(base::Tokens::statechange()));
                          },
                          worker_obj));
                }
              },
              context, worker, state));
    }
  }
}

bool ServiceWorkerJobs::ShouldSkipEvent(base::Token event_name,
                                        ServiceWorkerObject* worker) {
  // Algorithm for Should Skip Event:
  //   https://w3c.github.io/ServiceWorker/#should-skip-event-algorithm
  NOTIMPLEMENTED();
  return false;
}

void ServiceWorkerJobs::TerminateServiceWorker(ServiceWorkerObject* worker) {
  TRACE_EVENT0("cobalt::worker", "ServiceWorkerJobs::TerminateServiceWorker()");
  // Algorithm for Terminate Service Worker:
  //   https://w3c.github.io/ServiceWorker/#terminate-service-worker
  NOTIMPLEMENTED();
}

void ServiceWorkerJobs::Unregister(Job* job) {
  TRACE_EVENT0("cobalt::worker", "ServiceWorkerJobs::Unregister()");
  DCHECK_EQ(message_loop(), base::MessageLoop::current());
  // Algorithm for Unregister:
  //   https://w3c.github.io/ServiceWorker/#unregister-algorithm
  NOTIMPLEMENTED();
}

void ServiceWorkerJobs::RejectJobPromise(Job* job,
                                         const PromiseErrorData& error_data) {
  TRACE_EVENT0("cobalt::worker", "ServiceWorkerJobs::RejectJobPromise()");
  DCHECK_EQ(message_loop(), base::MessageLoop::current());
  // Algorithm for Reject Job Promise:
  //   https://w3c.github.io/ServiceWorker/#reject-job-promise
  // 1. If job’s client is not null, queue a task, on job’s client's responsible
  //    event loop using the DOM manipulation task source, to reject job’s job
  //    promise with a new exception with errorData and a user agent-defined
  //    message, in job’s client's Realm.

  auto reject_task = [](std::unique_ptr<JobPromiseType> promise,
                        const PromiseErrorData& error_data) {
    error_data.Reject(std::move(promise));
  };

  if (job->client) {
    base::AutoLock lock(job->equivalent_jobs_promise_mutex);
    job->client->context()->message_loop()->task_runner()->PostTask(
        FROM_HERE,
        base::BindOnce(reject_task, std::move(job->promise), error_data));
    // Ensure that the promise is cleared, so that equivalent jobs won't get
    // added from this point on.
    CHECK(!job->promise);
  }
  // 2. For each equivalentJob in job’s list of equivalent jobs:
  for (auto& equivalent_job : job->equivalent_jobs) {
    // Equivalent jobs should never have equivalent jobs of their own.
    DCHECK(equivalent_job->equivalent_jobs.empty());

    // 2.1. If equivalentJob’s client is null, continue.
    if (equivalent_job->client) {
      // 2.2. Queue a task, on equivalentJob’s client's responsible event loop
      //      using the DOM manipulation task source, to reject equivalentJob’s
      //      job promise with a new exception with errorData and a user
      //      agent-defined message, in equivalentJob’s client's Realm.
      equivalent_job->client->context()
          ->message_loop()
          ->task_runner()
          ->PostTask(
              FROM_HERE,
              base::BindOnce(reject_task, std::move(equivalent_job->promise),
                             error_data));
      // Check that the promise is cleared.
      CHECK(!equivalent_job->promise);
    }
  }
  job->equivalent_jobs.clear();
}

void ServiceWorkerJobs::ResolveJobPromise(
    Job* job, ServiceWorkerRegistrationObject* value) {
  TRACE_EVENT0("cobalt::worker", "ServiceWorkerJobs::ResolveJobPromise()");
  DCHECK_EQ(message_loop(), base::MessageLoop::current());
  DCHECK(job);
  DCHECK(value);
  // Algorithm for Resolve Job Promise:
  //   https://w3c.github.io/ServiceWorker/#resolve-job-promise-algorithm

  // 1. If job’s client is not null, queue a task, on job’s client's responsible
  //    event loop using the DOM manipulation task source, to run the following
  //    substeps:
  auto resolve_task = [](JobType type, web::EnvironmentSettings* client,
                         std::unique_ptr<JobPromiseType> promise,
                         ServiceWorkerRegistrationObject* value) {
    // 1.1./2.2.1. Let convertedValue be null.
    // 1.2./2.2.2. If job’s job type is either register or update, set
    //             convertedValue to the result of getting the service worker
    //             registration object that represents value in job’s client.
    if (type == kRegister || type == kUpdate) {
      scoped_refptr<cobalt::script::Wrappable> converted_value =
          client->context()->GetServiceWorkerRegistration(value);
      // 1.4./2.2.4.  Resolve job’s job promise with convertedValue.
      promise->Resolve(converted_value);
    } else {
      DCHECK_EQ(kUnregister, type);
      // 1.3./2.2.3. Else, set convertedValue to value, in job’s client's Realm.
      bool converted_value = value != nullptr;
      // 1.4./2.2.4.  Resolve job’s job promise with convertedValue.
      promise->Resolve(converted_value);
    }
  };

  if (job->client) {
    base::AutoLock lock(job->equivalent_jobs_promise_mutex);
    job->client->context()->message_loop()->task_runner()->PostTask(
        FROM_HERE, base::BindOnce(resolve_task, job->type, job->client,
                                  std::move(job->promise), value));
    // Ensure that the promise is cleared, so that equivalent jobs won't get
    // added from this point on.
    CHECK(!job->promise);
  }

  // 2. For each equivalentJob in job’s list of equivalent jobs:
  for (auto& equivalent_job : job->equivalent_jobs) {
    // Equivalent jobs should never have equivalent jobs of their own.
    DCHECK(equivalent_job->equivalent_jobs.empty());

    // 2.1. If equivalentJob’s client is null, continue to the next iteration of
    //      the loop.
    if (equivalent_job->client) {
      // 2.2. Queue a task, on equivalentJob’s client's responsible event loop
      //      using the DOM manipulation task source, to run the following
      //      substeps:
      equivalent_job->client->context()
          ->message_loop()
          ->task_runner()
          ->PostTask(FROM_HERE,
                     base::BindOnce(resolve_task, equivalent_job->type,
                                    equivalent_job->client,
                                    std::move(equivalent_job->promise), value));
      // Check that the promise is cleared.
      CHECK(!equivalent_job->promise);
    }
  }
  job->equivalent_jobs.clear();
}

// https://w3c.github.io/ServiceWorker/#finish-job-algorithm
void ServiceWorkerJobs::FinishJob(Job* job) {
  DCHECK_EQ(message_loop(), base::MessageLoop::current());
  // 1. Let jobQueue be job’s containing job queue.
  JobQueue* job_queue = job->containing_job_queue;

  // 2. Assert: the first item in jobQueue is job.
  DCHECK_EQ(job, job_queue->FirstItem());

  // 3. Dequeue from jobQueue.
  job_queue->Dequeue();

  // 4. If jobQueue is not empty, invoke Run Job with jobQueue.
  if (!job_queue->empty()) {
    RunJob(job_queue);
  }
}

void ServiceWorkerJobs::GetRegistrationSubSteps(
    const url::Origin& storage_key, const GURL& client_url,
    web::EnvironmentSettings* client,
    std::unique_ptr<script::ValuePromiseWrappable::Reference>
        promise_reference) {
  DCHECK_EQ(message_loop(), base::MessageLoop::current());
  // Algorithm for Sub steps of ServiceWorkerContainer.getRegistration():
  //   https://w3c.github.io/ServiceWorker/#navigator-service-worker-getRegistration

  // 1. Let registration be the result of running Match Service Worker
  //    Registration algorithm with clientURL as its argument.
  worker::ServiceWorkerRegistrationObject* registration =
      scope_to_registration_map_.MatchServiceWorkerRegistration(storage_key,
                                                                client_url);
  // 2. If registration is null, resolve promise with undefined and abort
  //    these steps.
  // 3. Resolve promise with the result of getting the service worker
  //    registration object that represents registration in promise’s
  //    relevant settings object.
  client->context()->message_loop()->task_runner()->PostTask(
      FROM_HERE,
      base::BindOnce(
          [](web::EnvironmentSettings* settings,
             std::unique_ptr<script::ValuePromiseWrappable::Reference> promise,
             ServiceWorkerRegistrationObject* registration) {
            promise->value().Resolve(
                settings->context()->GetServiceWorkerRegistration(
                    registration));
          },
          client, std::move(promise_reference), registration));
}

void ServiceWorkerJobs::RegisterWebContext(web::Context* context) {
  DCHECK_NE(nullptr, context);
  web_context_registrations_cleared_.Reset();
  if (base::MessageLoop::current() != message_loop()) {
    DCHECK(message_loop());
    message_loop()->task_runner()->PostTask(
        FROM_HERE, base::BindOnce(&ServiceWorkerJobs::RegisterWebContext,
                                  base::Unretained(this), context));
    return;
  }
  DCHECK_EQ(message_loop(), base::MessageLoop::current());
  DCHECK_EQ(0, web_context_registrations_.count(context));
  web_context_registrations_.insert(context);
}

void ServiceWorkerJobs::UnregisterWebContext(web::Context* context) {
  DCHECK_NE(nullptr, context);
  if (base::MessageLoop::current() != message_loop()) {
    // Block to ensure that the context is unregistered before it is destroyed.
    DCHECK(message_loop());
    message_loop()->task_runner()->PostBlockingTask(
        FROM_HERE, base::Bind(&ServiceWorkerJobs::UnregisterWebContext,
                              base::Unretained(this), context));
    return;
  }
  DCHECK_EQ(message_loop(), base::MessageLoop::current());
  DCHECK_EQ(1, web_context_registrations_.count(context));
  web_context_registrations_.erase(context);
  if (web_context_registrations_.empty()) {
    web_context_registrations_cleared_.Signal();
  }
}

ServiceWorkerJobs::JobPromiseType::JobPromiseType(
    std::unique_ptr<script::ValuePromiseBool::Reference> promise_reference)
    : promise_bool_reference_(std::move(promise_reference)) {}
ServiceWorkerJobs::JobPromiseType::JobPromiseType(
    std::unique_ptr<script::ValuePromiseWrappable::Reference> promise_reference)
    : promise_wrappable_reference_(std::move(promise_reference)) {}

void ServiceWorkerJobs::JobPromiseType::Resolve(const bool result) {
  DCHECK(promise_bool_reference_);
  promise_bool_reference_->value().Resolve(result);
}

void ServiceWorkerJobs::JobPromiseType::Resolve(
    const scoped_refptr<cobalt::script::Wrappable>& result) {
  DCHECK(promise_wrappable_reference_);
  promise_wrappable_reference_->value().Resolve(result);
}

void ServiceWorkerJobs::JobPromiseType::Reject(
    script::SimpleExceptionType exception) {
  if (promise_bool_reference_) {
    promise_bool_reference_->value().Reject(exception);
    return;
  }
  if (promise_wrappable_reference_) {
    promise_wrappable_reference_->value().Reject(exception);
    return;
  }
  NOTREACHED();
}

void ServiceWorkerJobs::JobPromiseType::Reject(
    const scoped_refptr<script::ScriptException>& result) {
  if (promise_bool_reference_) {
    promise_bool_reference_->value().Reject(result);
    return;
  }
  if (promise_wrappable_reference_) {
    promise_wrappable_reference_->value().Reject(result);
    return;
  }
  NOTREACHED();
}

script::PromiseState ServiceWorkerJobs::JobPromiseType::State() {
  if (promise_bool_reference_) {
    return promise_bool_reference_->value().State();
  }
  if (promise_wrappable_reference_) {
    return promise_wrappable_reference_->value().State();
  }
  NOTREACHED();
  return script::PromiseState::kPending;
}

}  // namespace worker
}  // namespace cobalt