/*
 * Copyright (C) 2008 Apple Inc. All Rights Reserved.
 * Copyright (C) 2012 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:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. 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.
 *
 * THIS SOFTWARE IS PROVIDED BY APPLE COMPUTER, INC. ``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 APPLE COMPUTER, INC. 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/core/execution_context/execution_context.h"

#include "third_party/blink/public/platform/task_type.h"
#include "third_party/blink/renderer/bindings/core/v8/source_location.h"
#include "third_party/blink/renderer/bindings/core/v8/v8_binding_for_core.h"
#include "third_party/blink/renderer/core/dom/events/event_target.h"
#include "third_party/blink/renderer/core/dom/pausable_object.h"
#include "third_party/blink/renderer/core/events/error_event.h"
#include "third_party/blink/renderer/core/fileapi/public_url_manager.h"
#include "third_party/blink/renderer/core/frame/use_counter.h"
#include "third_party/blink/renderer/core/inspector/console_message.h"
#include "third_party/blink/renderer/core/probe/core_probes.h"
#include "third_party/blink/renderer/core/workers/worker_global_scope.h"
#include "third_party/blink/renderer/core/workers/worker_thread.h"
#include "third_party/blink/renderer/platform/loader/fetch/fetch_client_settings_object_snapshot.h"
#include "third_party/blink/renderer/platform/loader/fetch/memory_cache.h"
#include "third_party/blink/renderer/platform/weborigin/security_policy.h"

namespace blink {

ExecutionContext::ExecutionContext()
    : circular_sequential_id_(0),
      in_dispatch_error_event_(false),
      is_context_paused_(false),
      is_context_destroyed_(false),
      window_interaction_tokens_(0),
      referrer_policy_(kReferrerPolicyDefault),
      invalidator_(std::make_unique<InterfaceInvalidator>()) {}

ExecutionContext::~ExecutionContext() = default;

// static
ExecutionContext* ExecutionContext::From(const ScriptState* script_state) {
  v8::HandleScope scope(script_state->GetIsolate());
  return ToExecutionContext(script_state->GetContext());
}

// static
ExecutionContext* ExecutionContext::ForCurrentRealm(
    const v8::FunctionCallbackInfo<v8::Value>& info) {
  return ToExecutionContext(info.GetIsolate()->GetCurrentContext());
}

// static
ExecutionContext* ExecutionContext::ForRelevantRealm(
    const v8::FunctionCallbackInfo<v8::Value>& info) {
  return ToExecutionContext(info.Holder()->CreationContext());
}

void ExecutionContext::PausePausableObjects() {
  DCHECK(!is_context_paused_);
  NotifySuspendingPausableObjects();
  is_context_paused_ = true;
}

void ExecutionContext::UnpausePausableObjects() {
  DCHECK(is_context_paused_);
  is_context_paused_ = false;
  NotifyResumingPausableObjects();
}

void ExecutionContext::NotifyContextDestroyed() {
  is_context_destroyed_ = true;
  invalidator_.reset();
  ContextLifecycleNotifier::NotifyContextDestroyed();
}

void ExecutionContext::PauseScheduledTasks() {
  PausePausableObjects();
  TasksWerePaused();
}

void ExecutionContext::UnpauseScheduledTasks() {
  UnpausePausableObjects();
  TasksWereUnpaused();
}

void ExecutionContext::PausePausableObjectIfNeeded(PausableObject* object) {
#if DCHECK_IS_ON()
  DCHECK(Contains(object));
#endif
  // Ensure all PausableObjects are paused also newly created ones.
  if (is_context_paused_)
    object->Pause();
}

void ExecutionContext::DispatchErrorEvent(
    ErrorEvent* error_event,
    SanitizeScriptErrors sanitize_script_errors) {
  if (in_dispatch_error_event_) {
    pending_exceptions_.push_back(error_event);
    return;
  }

  // First report the original exception and only then all the nested ones.
  if (!DispatchErrorEventInternal(error_event, sanitize_script_errors))
    ExceptionThrown(error_event);

  if (pending_exceptions_.IsEmpty())
    return;
  for (ErrorEvent* e : pending_exceptions_)
    ExceptionThrown(e);
  pending_exceptions_.clear();
}

bool ExecutionContext::DispatchErrorEventInternal(
    ErrorEvent* error_event,
    SanitizeScriptErrors sanitize_script_errors) {
  EventTarget* target = ErrorEventTarget();
  if (!target)
    return false;

  if (sanitize_script_errors == SanitizeScriptErrors::kSanitize) {
    error_event = ErrorEvent::CreateSanitizedError(
        ToScriptState(this, *error_event->World()));
  }

  DCHECK(!in_dispatch_error_event_);
  in_dispatch_error_event_ = true;
  target->DispatchEvent(*error_event);
  in_dispatch_error_event_ = false;
  return error_event->defaultPrevented();
}

int ExecutionContext::CircularSequentialID() {
  ++circular_sequential_id_;
  if (circular_sequential_id_ > ((1U << 31) - 1U))
    circular_sequential_id_ = 1;

  return circular_sequential_id_;
}

PublicURLManager& ExecutionContext::GetPublicURLManager() {
  if (!public_url_manager_)
    public_url_manager_ = PublicURLManager::Create(this);
  return *public_url_manager_;
}

const SecurityOrigin* ExecutionContext::GetSecurityOrigin() {
  return GetSecurityContext().GetSecurityOrigin();
}

SecurityOrigin* ExecutionContext::GetMutableSecurityOrigin() {
  return GetSecurityContext().GetMutableSecurityOrigin();
}

ContentSecurityPolicy* ExecutionContext::GetContentSecurityPolicy() {
  return GetSecurityContext().GetContentSecurityPolicy();
}

void ExecutionContext::AllowWindowInteraction() {
  ++window_interaction_tokens_;
}

void ExecutionContext::ConsumeWindowInteraction() {
  if (window_interaction_tokens_ == 0)
    return;
  --window_interaction_tokens_;
}

bool ExecutionContext::IsWindowInteractionAllowed() const {
  return window_interaction_tokens_ > 0;
}

bool ExecutionContext::IsSecureContext() const {
  String unused_error_message;
  return IsSecureContext(unused_error_message);
}

// https://w3c.github.io/webappsec-referrer-policy/#determine-requests-referrer
String ExecutionContext::OutgoingReferrer() const {
  // Step 3.1: "If environment's global object is a Window object, then"
  // This case is implemented in Document::OutgoingReferrer().

  // Step 3.2: "Otherwise, let referrerSource be environment's creation URL."
  return Url().StrippedForUseAsReferrer();
}

FetchClientSettingsObjectSnapshot*
ExecutionContext::CreateFetchClientSettingsObjectSnapshot() {
  return new FetchClientSettingsObjectSnapshot(
      BaseURL(), GetSecurityOrigin(), GetReferrerPolicy(), OutgoingReferrer(),
      GetHttpsState());
}

void ExecutionContext::ParseAndSetReferrerPolicy(const String& policies,
                                                 bool support_legacy_keywords) {
  ReferrerPolicy referrer_policy;

  if (!SecurityPolicy::ReferrerPolicyFromHeaderValue(
          policies,
          support_legacy_keywords ? kSupportReferrerPolicyLegacyKeywords
                                  : kDoNotSupportReferrerPolicyLegacyKeywords,
          &referrer_policy)) {
    AddConsoleMessage(ConsoleMessage::Create(
        kRenderingMessageSource, kErrorMessageLevel,
        "Failed to set referrer policy: The value '" + policies +
            "' is not one of " +
            (support_legacy_keywords
                 ? "'always', 'default', 'never', 'origin-when-crossorigin', "
                 : "") +
            "'no-referrer', 'no-referrer-when-downgrade', 'origin', "
            "'origin-when-cross-origin', 'same-origin', 'strict-origin', "
            "'strict-origin-when-cross-origin', or 'unsafe-url'. The referrer "
            "policy "
            "has been left unchanged."));
    return;
  }

  SetReferrerPolicy(referrer_policy);
}

void ExecutionContext::SetReferrerPolicy(ReferrerPolicy referrer_policy) {
  // When a referrer policy has already been set, the latest value takes
  // precedence.
  UseCounter::Count(this, WebFeature::kSetReferrerPolicy);
  if (referrer_policy_ != kReferrerPolicyDefault)
    UseCounter::Count(this, WebFeature::kResetReferrerPolicy);

  referrer_policy_ = referrer_policy;
}

void ExecutionContext::RemoveURLFromMemoryCache(const KURL& url) {
  GetMemoryCache()->RemoveURLFromCache(url);
}

void ExecutionContext::Trace(blink::Visitor* visitor) {
  visitor->Trace(public_url_manager_);
  visitor->Trace(pending_exceptions_);
  ContextLifecycleNotifier::Trace(visitor);
  Supplementable<ExecutionContext>::Trace(visitor);
}

bool ExecutionContext::IsSameAgentCluster(
    const base::UnguessableToken& other_id) const {
  base::UnguessableToken this_id = GetAgentClusterID();
  // If the AgentClusterID is empty then it should never be the same (e.g.
  // currently for worklets).
  if (this_id.is_empty() || other_id.is_empty())
    return false;
  return this_id == other_id;
}

}  // namespace blink