/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* vim:set ts=2 sts=2 sw=2 et cin: */
/* 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 "ToastNotification.h"

#include <windows.h>
#include <appmodel.h>
#include <ktmw32.h>
#include <windows.foundation.h>
#include <wrl/client.h>

#include "ErrorList.h"
#include "mozilla/BasePrincipal.h"
#include "mozilla/Buffer.h"
#include "mozilla/dom/Promise.h"
#include "mozilla/DynamicallyLinkedFunctionPtr.h"
#include "mozilla/ErrorResult.h"
#include "mozilla/mscom/COMWrappers.h"
#include "mozilla/mscom/Utils.h"
#include "mozilla/Logging.h"
#include "mozilla/Services.h"
#include "mozilla/WidgetUtils.h"
#include "mozilla/WindowsVersion.h"
#include "nsAppRunner.h"
#include "nsComponentManagerUtils.h"
#include "nsCOMPtr.h"
#include "nsIObserverService.h"
#include "nsIWindowMediator.h"
#include "nsPIDOMWindow.h"
#include "nsString.h"
#include "nsThreadUtils.h"
#include "nsWindowsHelpers.h"
#include "nsXREDirProvider.h"
#include "prenv.h"
#include "ToastNotificationHandler.h"
#include "ToastNotificationHeaderOnlyUtils.h"
#include "WinTaskbar.h"
#include "WinUtils.h"

namespace mozilla {
namespace widget {

using namespace toastnotification;

using namespace ABI::Windows::Foundation;
using namespace Microsoft::WRL;
using namespace Microsoft::WRL::Wrappers;
// Needed to disambiguate internal and Windows `ToastNotification` classes.
using namespace ABI::Windows::UI::Notifications;
using WinToastNotification = ABI::Windows::UI::Notifications::ToastNotification;
using IVectorView_ToastNotification =
    ABI::Windows::Foundation::Collections::IVectorView<WinToastNotification*>;
using IVectorView_ScheduledToastNotification =
    ABI::Windows::Foundation::Collections::IVectorView<
        ScheduledToastNotification*>;

LazyLogModule sWASLog("WindowsAlertsService");

NS_IMPL_ISUPPORTS(ToastNotification, nsIAlertsService, nsIWindowsAlertsService,
                  nsIAlertsDoNotDisturb, nsIObserver)

ToastNotification::ToastNotification() = default;

ToastNotification::~ToastNotification() = default;

nsresult ToastNotification::Init() {
  if (!IsWin8OrLater()) {
    return NS_ERROR_NOT_IMPLEMENTED;
  }

  if (!PR_GetEnv("XPCSHELL_TEST_PROFILE_DIR")) {
    // Windows Toast Notification requires AppId.  But allow `xpcshell` to
    // create the service to test other functionality.
    if (!EnsureAumidRegistered()) {
      MOZ_LOG(sWASLog, LogLevel::Warning, ("Failed to register AUMID!"));
      return NS_ERROR_NOT_IMPLEMENTED;
    }
  } else {
    MOZ_LOG(sWASLog, LogLevel::Info, ("Using dummy AUMID in xpcshell test"));
    mAumid.emplace(u"XpcshellTestToastAumid"_ns);
  }

  MOZ_LOG(sWASLog, LogLevel::Info,
          ("Using AUMID: '%s'", NS_ConvertUTF16toUTF8(mAumid.ref()).get()));

  nsCOMPtr<nsIObserverService> obsServ =
      mozilla::services::GetObserverService();
  if (obsServ) {
    Unused << NS_WARN_IF(
        NS_FAILED(obsServ->AddObserver(this, "last-pb-context-exited", false)));
    Unused << NS_WARN_IF(
        NS_FAILED(obsServ->AddObserver(this, "quit-application", false)));
  }

  return NS_OK;
}

bool ToastNotification::EnsureAumidRegistered() {
  // Check if this is an MSIX install, app identity is provided by the package
  // so no registration is necessary.
  if (AssignIfMsixAumid(mAumid)) {
    MOZ_LOG(
        sWASLog, LogLevel::Info,
        ("Found MSIX AUMID: '%s'", NS_ConvertUTF16toUTF8(mAumid.ref()).get()));
    return true;
  }

  // Fall back to start menu shortcut for Windows 8; toast AUMID registration in
  // the registry only works in Windows 10+.
  if (!IsWin10OrLater()) {
    nsAutoString aumid;
    if (!WinTaskbar::GetAppUserModelID(aumid)) {
      return false;
    }

    mAumid = Some(aumid);
    return true;
  }

  nsAutoString installHash;
  nsresult rv = gDirServiceProvider->GetInstallHash(installHash);
  NS_ENSURE_SUCCESS(rv, false);

  // Check if toasts were registered during NSIS/MSI installation.
  if (AssignIfNsisAumid(installHash, mAumid)) {
    MOZ_LOG(sWASLog, LogLevel::Info,
            ("Found AUMID from installer (with install hash '%s'): '%s'",
             NS_ConvertUTF16toUTF8(installHash).get(),
             NS_ConvertUTF16toUTF8(mAumid.ref()).get()));
    return true;
  }

  // No AUMID registered, fall through to runtime registration for development
  // and portable builds.
  if (RegisterRuntimeAumid(installHash, mAumid)) {
    MOZ_LOG(
        sWASLog, LogLevel::Info,
        ("Updated AUMID registration at runtime (for install hash '%s'): '%s'",
         NS_ConvertUTF16toUTF8(installHash).get(),
         NS_ConvertUTF16toUTF8(mAumid.ref()).get()));
    return true;
  }

  MOZ_LOG(sWASLog, LogLevel::Warning,
          ("Failed to register AUMID at runtime! (for install hash '%s')",
           NS_ConvertUTF16toUTF8(installHash).get()));
  return false;
}

bool ToastNotification::AssignIfMsixAumid(Maybe<nsAutoString>& aAumid) {
  // `GetCurrentApplicationUserModelId` added in Windows 8.
  DynamicallyLinkedFunctionPtr<decltype(&GetCurrentApplicationUserModelId)>
      pGetCurrentApplicationUserModelId(L"kernel32.dll",
                                        "GetCurrentApplicationUserModelId");
  if (!pGetCurrentApplicationUserModelId) {
    return false;
  }

  UINT32 len = 0;
  // ERROR_INSUFFICIENT_BUFFER signals that we're in an MSIX package, and
  // therefore should use the package's AUMID.
  if (pGetCurrentApplicationUserModelId(&len, nullptr) !=
      ERROR_INSUFFICIENT_BUFFER) {
    MOZ_LOG(sWASLog, LogLevel::Debug, ("Not an MSIX package"));
    return false;
  }
  mozilla::Buffer<wchar_t> buffer(len);
  LONG success = pGetCurrentApplicationUserModelId(&len, buffer.Elements());
  NS_ENSURE_TRUE(success == ERROR_SUCCESS, false);

  aAumid.emplace(buffer.Elements());
  return true;
}

bool ToastNotification::AssignIfNsisAumid(nsAutoString& aInstallHash,
                                          Maybe<nsAutoString>& aAumid) {
  nsAutoString nsisAumidName =
      u""_ns MOZ_TOAST_APP_NAME u"Toast-"_ns + aInstallHash;
  nsAutoString nsisAumidPath = u"AppUserModelId\\"_ns + nsisAumidName;
  if (!WinUtils::HasRegistryKey(HKEY_CLASSES_ROOT, nsisAumidPath.get())) {
    MOZ_LOG(sWASLog, LogLevel::Debug,
            ("No CustomActivator value from installer in key 'HKCR\\%s'",
             NS_ConvertUTF16toUTF8(nsisAumidPath).get()));
    return false;
  }

  aAumid.emplace(nsisAumidName);
  return true;
}

bool ToastNotification::RegisterRuntimeAumid(nsAutoString& aInstallHash,
                                             Maybe<nsAutoString>& aAumid) {
  // Portable AUMID slightly differs from installed AUMID so we can
  // differentiate installed to HKCU vs portable installs if necessary.
  nsAutoString portableAumid =
      u""_ns MOZ_TOAST_APP_NAME u"PortableToast-"_ns + aInstallHash;

  nsCOMPtr<nsIFile> appdir;
  nsresult rv = gDirServiceProvider->GetGREDir()->Clone(getter_AddRefs(appdir));
  NS_ENSURE_SUCCESS(rv, false);

  nsCOMPtr<nsIFile> icon;
  rv = appdir->Clone(getter_AddRefs(icon));
  NS_ENSURE_SUCCESS(rv, false);

  rv = icon->Append(u"browser"_ns);
  NS_ENSURE_SUCCESS(rv, false);

  rv = icon->Append(u"VisualElements"_ns);
  NS_ENSURE_SUCCESS(rv, false);

  rv = icon->Append(u"VisualElements_70.png"_ns);
  NS_ENSURE_SUCCESS(rv, false);

  nsAutoString iconPath;
  rv = icon->GetPath(iconPath);
  NS_ENSURE_SUCCESS(rv, false);

  nsCOMPtr<nsIFile> comDll;
  rv = appdir->Clone(getter_AddRefs(comDll));
  NS_ENSURE_SUCCESS(rv, false);

  rv = comDll->Append(u"notificationserver.dll"_ns);
  NS_ENSURE_SUCCESS(rv, false);

  nsAutoString dllPath;
  rv = comDll->GetPath(dllPath);
  NS_ENSURE_SUCCESS(rv, false);

  nsAutoHandle txn;
  // Manipulate the registry using a transaction so that any failures are
  // rolled back.
  wchar_t transactionName[] = L"" MOZ_TOAST_APP_NAME L" toast registration";
  txn.own(::CreateTransaction(nullptr, nullptr, TRANSACTION_DO_NOT_PROMOTE, 0,
                              0, 0, transactionName));
  NS_ENSURE_TRUE(txn.get() != INVALID_HANDLE_VALUE, false);

  LSTATUS status;

  auto RegisterKey = [&](const nsAString& path, nsAutoRegKey& key) {
    HKEY rawKey;
    status = ::RegCreateKeyTransactedW(
        HKEY_CURRENT_USER, PromiseFlatString(path).get(), 0, nullptr,
        REG_OPTION_NON_VOLATILE, KEY_ALL_ACCESS, nullptr, &rawKey, nullptr, txn,
        nullptr);
    NS_ENSURE_TRUE(status == ERROR_SUCCESS, false);

    key.own(rawKey);
    return true;
  };
  auto RegisterValue = [&](nsAutoRegKey& key, const nsAString& name,
                           unsigned long type, const nsAString& data) {
    status = ::RegSetValueExW(
        key, PromiseFlatString(name).get(), 0, type,
        static_cast<const BYTE*>(PromiseFlatString(data).get()),
        (data.Length() + 1) * sizeof(wchar_t));

    return status == ERROR_SUCCESS;
  };

  // clang-format off
  /* Writes the following keys and values to the registry.
   * HKEY_CURRENT_USER\Software\Classes\AppID\{GUID}                                                      DllSurrogate    : REG_SZ        = ""
   *                                   \AppUserModelId\{MOZ_TOAST_APP_NAME}PortableToast-{install hash}   CustomActivator : REG_SZ        = {GUID}
   *                                                                                                      DisplayName     : REG_EXPAND_SZ = {display name}
   *                                                                                                      IconUri         : REG_EXPAND_SZ = {icon path}
   *                                   \CLSID\{GUID}                                                      AppID           : REG_SZ        = {GUID}
   *                                                \InprocServer32                                       (Default)       : REG_SZ        = {notificationserver.dll path}
   */
  // clang-format on

  constexpr nsLiteralString classes = u"Software\\Classes\\"_ns;

  nsAutoString aumid = classes + u"AppUserModelId\\"_ns + portableAumid;
  nsAutoRegKey aumidKey;
  NS_ENSURE_TRUE(RegisterKey(aumid, aumidKey), false);

  nsAutoString guidStr;
  {
    DWORD bufferSizeBytes = NSID_LENGTH * sizeof(wchar_t);
    Buffer<wchar_t> guidBuffer(bufferSizeBytes);
    status = ::RegGetValueW(HKEY_CURRENT_USER, aumid.get(), L"CustomActivator",
                            RRF_RT_REG_SZ, 0, guidBuffer.Elements(),
                            &bufferSizeBytes);

    CLSID unused;
    if (status == ERROR_SUCCESS &&
        SUCCEEDED(CLSIDFromString(guidBuffer.Elements(), &unused))) {
      guidStr = guidBuffer.Elements();
    } else {
      nsIDToCString uuidString(nsID::GenerateUUID());
      size_t len = strlen(uuidString.get());
      MOZ_ASSERT(len == NSID_LENGTH - 1);
      CopyASCIItoUTF16(nsDependentCSubstring(uuidString.get(), len), guidStr);
    }

    if (status == ERROR_SUCCESS) {
      MOZ_LOG(sWASLog, LogLevel::Debug,
              ("Existing CustomActivator guid found: '%s'",
               NS_ConvertUTF16toUTF8(guidStr).get()));
    } else {
      MOZ_LOG(sWASLog, LogLevel::Debug,
              ("New CustomActivator guid generated: '%s'",
               NS_ConvertUTF16toUTF8(guidStr).get()));
    }
  }
  NS_ENSURE_TRUE(
      RegisterValue(aumidKey, u"CustomActivator"_ns, REG_SZ, guidStr), false);
  nsAutoString brandName;
  WidgetUtils::GetBrandShortName(brandName);
  NS_ENSURE_TRUE(
      RegisterValue(aumidKey, u"DisplayName"_ns, REG_EXPAND_SZ, brandName),
      false);
  NS_ENSURE_TRUE(
      RegisterValue(aumidKey, u"IconUri"_ns, REG_EXPAND_SZ, iconPath), false);

  nsAutoString appid = classes + u"AppID\\"_ns + guidStr;
  nsAutoRegKey appidKey;
  NS_ENSURE_TRUE(RegisterKey(appid, appidKey), false);
  NS_ENSURE_TRUE(RegisterValue(appidKey, u"DllSurrogate"_ns, REG_SZ, u""_ns),
                 false);

  nsAutoString clsid = classes + u"CLSID\\"_ns + guidStr;
  nsAutoRegKey clsidKey;
  NS_ENSURE_TRUE(RegisterKey(clsid, clsidKey), false);
  NS_ENSURE_TRUE(RegisterValue(clsidKey, u"AppID"_ns, REG_SZ, guidStr), false);

  nsAutoString inproc = clsid + u"\\InprocServer32"_ns;
  nsAutoRegKey inprocKey;
  NS_ENSURE_TRUE(RegisterKey(inproc, inprocKey), false);
  // Set the component's path to this DLL
  NS_ENSURE_TRUE(RegisterValue(inprocKey, u""_ns, REG_SZ, dllPath), false);

  NS_ENSURE_TRUE(::CommitTransaction(txn), false);

  MOZ_LOG(
      sWASLog, LogLevel::Debug,
      ("Updated registration for CustomActivator value in key 'HKCU\\%s': '%s'",
       NS_ConvertUTF16toUTF8(aumid).get(),
       NS_ConvertUTF16toUTF8(guidStr).get()));
  aAumid.emplace(portableAumid);
  return true;
}

nsresult ToastNotification::BackgroundDispatch(nsIRunnable* runnable) {
  return NS_DispatchBackgroundTask(runnable);
}

NS_IMETHODIMP
ToastNotification::GetSuppressForScreenSharing(bool* aRetVal) {
  *aRetVal = mSuppressForScreenSharing;
  return NS_OK;
}

NS_IMETHODIMP
ToastNotification::SetSuppressForScreenSharing(bool aSuppress) {
  mSuppressForScreenSharing = aSuppress;
  return NS_OK;
}

NS_IMETHODIMP
ToastNotification::Observe(nsISupports* aSubject, const char* aTopic,
                           const char16_t* aData) {
  nsDependentCString topic(aTopic);

  for (auto iter = mActiveHandlers.Iter(); !iter.Done(); iter.Next()) {
    RefPtr<ToastNotificationHandler> handler = iter.UserData();

    auto removeNotification = [&]() {
      // The handlers' destructors will do the right thing (de-register with
      // Windows).
      iter.Remove();

      // Break the cycle between the handler and the MSCOM notification so the
      // handler's destructor will be called.
      handler->UnregisterHandler();
    };

    if (topic == "last-pb-context-exited"_ns) {
      if (handler->IsPrivate()) {
        handler->HideAlert();
        removeNotification();
      }
    } else if (topic == "quit-application"_ns) {
      removeNotification();
    }
  }

  return NS_OK;
}

NS_IMETHODIMP
ToastNotification::ShowAlertNotification(
    const nsAString& aImageUrl, const nsAString& aAlertTitle,
    const nsAString& aAlertText, bool aAlertTextClickable,
    const nsAString& aAlertCookie, nsIObserver* aAlertListener,
    const nsAString& aAlertName, const nsAString& aBidi, const nsAString& aLang,
    const nsAString& aData, nsIPrincipal* aPrincipal, bool aInPrivateBrowsing,
    bool aRequireInteraction) {
  nsCOMPtr<nsIAlertNotification> alert =
      do_CreateInstance(ALERT_NOTIFICATION_CONTRACTID);
  if (NS_WARN_IF(!alert)) {
    return NS_ERROR_FAILURE;
  }
  // vibrate is unused for now
  nsTArray<uint32_t> vibrate;
  nsresult rv = alert->Init(aAlertName, aImageUrl, aAlertTitle, aAlertText,
                            aAlertTextClickable, aAlertCookie, aBidi, aLang,
                            aData, aPrincipal, aInPrivateBrowsing,
                            aRequireInteraction, false, vibrate);
  if (NS_WARN_IF(NS_FAILED(rv))) {
    return rv;
  }
  return ShowAlert(alert, aAlertListener);
}

NS_IMETHODIMP
ToastNotification::ShowPersistentNotification(const nsAString& aPersistentData,
                                              nsIAlertNotification* aAlert,
                                              nsIObserver* aAlertListener) {
  return ShowAlert(aAlert, aAlertListener);
}

NS_IMETHODIMP
ToastNotification::SetManualDoNotDisturb(bool aDoNotDisturb) {
  return NS_ERROR_NOT_IMPLEMENTED;
}

NS_IMETHODIMP
ToastNotification::GetManualDoNotDisturb(bool* aRet) {
  return NS_ERROR_NOT_IMPLEMENTED;
}

NS_IMETHODIMP
ToastNotification::ShowAlert(nsIAlertNotification* aAlert,
                             nsIObserver* aAlertListener) {
  NS_ENSURE_ARG(aAlert);

  if (mSuppressForScreenSharing) {
    return NS_OK;
  }

  nsAutoString cookie;
  MOZ_TRY(aAlert->GetCookie(cookie));

  nsAutoString name;
  MOZ_TRY(aAlert->GetName(name));

  nsAutoString title;
  MOZ_TRY(aAlert->GetTitle(title));
  if (!EnsureUTF16Validity(title)) {
    MOZ_LOG(sWASLog, LogLevel::Warning,
            ("Notification title was invalid UTF16, unpaired surrogates have "
             "been replaced."));
  }

  nsAutoString text;
  MOZ_TRY(aAlert->GetText(text));
  if (!EnsureUTF16Validity(text)) {
    MOZ_LOG(sWASLog, LogLevel::Warning,
            ("Notification text was invalid UTF16, unpaired surrogates have "
             "been replaced."));
  }

  bool textClickable;
  MOZ_TRY(aAlert->GetTextClickable(&textClickable));

  bool isSilent;
  MOZ_TRY(aAlert->GetSilent(&isSilent));

  nsAutoString hostPort;
  MOZ_TRY(aAlert->GetSource(hostPort));

  nsAutoString launchUrl;
  MOZ_TRY(aAlert->GetLaunchURL(launchUrl));

  bool requireInteraction;
  MOZ_TRY(aAlert->GetRequireInteraction(&requireInteraction));

  bool inPrivateBrowsing;
  MOZ_TRY(aAlert->GetInPrivateBrowsing(&inPrivateBrowsing));

  nsTArray<RefPtr<nsIAlertAction>> actions;
  MOZ_TRY(aAlert->GetActions(actions));

  nsCOMPtr<nsIPrincipal> principal;
  MOZ_TRY(aAlert->GetPrincipal(getter_AddRefs(principal)));
  bool isSystemPrincipal = principal && principal->IsSystemPrincipal();

  RefPtr<ToastNotificationHandler> oldHandler = mActiveHandlers.Get(name);

  NS_ENSURE_TRUE(mAumid.isSome(), NS_ERROR_UNEXPECTED);
  RefPtr<ToastNotificationHandler> handler = new ToastNotificationHandler(
      this, mAumid.ref(), aAlertListener, name, cookie, title, text, hostPort,
      textClickable, requireInteraction, actions, isSystemPrincipal, launchUrl,
      inPrivateBrowsing, isSilent);
  mActiveHandlers.InsertOrUpdate(name, RefPtr{handler});

  MOZ_LOG(sWASLog, LogLevel::Debug,
          ("Adding handler '%s': [%p] (now %d handlers)",
           NS_ConvertUTF16toUTF8(name).get(), handler.get(),
           mActiveHandlers.Count()));

  nsresult rv = handler->InitAlertAsync(aAlert);
  if (NS_WARN_IF(NS_FAILED(rv))) {
    MOZ_LOG(sWASLog, LogLevel::Debug,
            ("Failed to init alert, removing '%s'",
             NS_ConvertUTF16toUTF8(name).get()));
    mActiveHandlers.Remove(name);
    handler->UnregisterHandler();
    return rv;
  }

  // If there was a previous handler with the same name then unregister it.
  if (oldHandler) {
    oldHandler->UnregisterHandler();
  }

  return NS_OK;
}

NS_IMETHODIMP
ToastNotification::GetXmlStringForWindowsAlert(nsIAlertNotification* aAlert,
                                               const nsAString& aWindowsTag,
                                               nsAString& aString) {
  NS_ENSURE_ARG(aAlert);

  nsAutoString cookie;
  MOZ_TRY(aAlert->GetCookie(cookie));

  nsAutoString name;
  MOZ_TRY(aAlert->GetName(name));

  nsAutoString title;
  MOZ_TRY(aAlert->GetTitle(title));

  nsAutoString text;
  MOZ_TRY(aAlert->GetText(text));

  bool textClickable;
  MOZ_TRY(aAlert->GetTextClickable(&textClickable));

  bool isSilent;
  MOZ_TRY(aAlert->GetSilent(&isSilent));

  nsAutoString hostPort;
  MOZ_TRY(aAlert->GetSource(hostPort));

  nsAutoString launchUrl;
  MOZ_TRY(aAlert->GetLaunchURL(launchUrl));

  bool requireInteraction;
  MOZ_TRY(aAlert->GetRequireInteraction(&requireInteraction));

  bool inPrivateBrowsing;
  MOZ_TRY(aAlert->GetInPrivateBrowsing(&inPrivateBrowsing));

  nsTArray<RefPtr<nsIAlertAction>> actions;
  MOZ_TRY(aAlert->GetActions(actions));

  nsCOMPtr<nsIPrincipal> principal;
  MOZ_TRY(aAlert->GetPrincipal(getter_AddRefs(principal)));
  bool isSystemPrincipal = principal && principal->IsSystemPrincipal();

  NS_ENSURE_TRUE(mAumid.isSome(), NS_ERROR_UNEXPECTED);
  RefPtr<ToastNotificationHandler> handler = new ToastNotificationHandler(
      this, mAumid.ref(), nullptr /* aAlertListener */, name, cookie, title,
      text, hostPort, textClickable, requireInteraction, actions,
      isSystemPrincipal, launchUrl, inPrivateBrowsing, isSilent);

  // Usually, this will be empty during testing, making test output
  // deterministic.
  MOZ_TRY(handler->SetWindowsTag(aWindowsTag));

  nsAutoString imageURL;
  MOZ_TRY(aAlert->GetImageURL(imageURL));

  return handler->CreateToastXmlString(imageURL, aString);
}

// Verifies that the tag recieved associates to a notification created during
// this application's session, or handles fallback behavior.
RefPtr<ToastHandledPromise> ToastNotification::VerifyTagPresentOrFallback(
    const nsAString& aWindowsTag) {
  MOZ_LOG(sWASLog, LogLevel::Debug,
          ("Iterating %d handlers", mActiveHandlers.Count()));

  for (auto iter = mActiveHandlers.Iter(); !iter.Done(); iter.Next()) {
    RefPtr<ToastNotificationHandler> handler = iter.UserData();
    nsAutoString tag;
    nsresult rv = handler->GetWindowsTag(tag);

    if (NS_SUCCEEDED(rv)) {
      MOZ_LOG(sWASLog, LogLevel::Debug,
              ("Comparing external windowsTag '%s' to handled windowsTag '%s'",
               NS_ConvertUTF16toUTF8(aWindowsTag).get(),
               NS_ConvertUTF16toUTF8(tag).get()));
      if (aWindowsTag.Equals(tag)) {
        MOZ_LOG(sWASLog, LogLevel::Debug,
                ("External windowsTag '%s' is handled by handler [%p]",
                 NS_ConvertUTF16toUTF8(aWindowsTag).get(), handler.get()));
        ToastHandledResolve handled{u""_ns, u""_ns};
        return ToastHandledPromise::CreateAndResolve(handled, __func__);
      }
    } else {
      MOZ_LOG(sWASLog, LogLevel::Debug,
              ("Failed to get windowsTag for handler [%p]", handler.get()));
    }
  }

  // Fallback handling

  RefPtr<ToastHandledPromise::Private> fallbackPromise =
      new ToastHandledPromise::Private(__func__);

  // TODO: Bug 1806005 - At time of writing this function is called in a call
  // stack containing `WndProc` callback on an STA thread. As a result attempts
  // to create a `ToastNotificationManager` instance results an an
  // `RPC_E_CANTCALLOUT_ININPUTSYNCCALL` error. We can simplify the the XPCOM
  // interface and synchronize the COM interactions if notification fallback
  // handling were no longer handled in a `WndProc` context.
  NS_DispatchBackgroundTask(NS_NewRunnableFunction(
      "VerifyTagPresentOrFallback fallback background task",
      [fallbackPromise, aWindowsTag = nsString(aWindowsTag),
       aAumid = nsString(mAumid.ref())]() {
        MOZ_ASSERT(mscom::IsCOMInitializedOnCurrentThread());

        bool foundTag;
        nsAutoString launchUrl;
        nsAutoString privilegedName;

        nsresult rv = ToastNotificationHandler::
            FindLaunchURLAndPrivilegedNameForWindowsTag(
                aWindowsTag, aAumid, foundTag, launchUrl, privilegedName);

        if (NS_FAILED(rv) || !foundTag) {
          MOZ_LOG(sWASLog, LogLevel::Error,
                  ("Failed to get launch URL and privileged name for "
                   "notification tag '%s'",
                   NS_ConvertUTF16toUTF8(aWindowsTag).get()));

          fallbackPromise->Reject(false, __func__);
          return;
        }

        MOZ_LOG(sWASLog, LogLevel::Debug,
                ("Found launch URL '%s' and privileged name '%s' for "
                 "windowsTag '%s'",
                 NS_ConvertUTF16toUTF8(launchUrl).get(),
                 NS_ConvertUTF16toUTF8(privilegedName).get(),
                 NS_ConvertUTF16toUTF8(aWindowsTag).get()));

        ToastHandledResolve handled{launchUrl, privilegedName};
        fallbackPromise->Resolve(handled, __func__);
      }));

  return fallbackPromise;
}

// Send our window's PID to the notification server so that it can grant us
// `SetForegroundWindow` permissions. PID 0 is sent to signal no window PID.
// Absense of PID which may occur when we are yet unable to retrieve the
// window during startup, which is not a problem in practice as new windows
// receive focus by default.
void ToastNotification::SignalComNotificationHandled(
    const nsAString& aWindowsTag) {
  DWORD pid = 0;

  nsCOMPtr<nsIWindowMediator> winMediator(
      do_GetService(NS_WINDOWMEDIATOR_CONTRACTID));
  if (winMediator) {
    nsCOMPtr<mozIDOMWindowProxy> navWin;
    winMediator->GetMostRecentWindow(u"navigator:browser",
                                     getter_AddRefs(navWin));
    if (navWin) {
      nsCOMPtr<nsIWidget> widget =
          WidgetUtils::DOMWindowToWidget(nsPIDOMWindowOuter::From(navWin));
      if (widget) {
        HWND hwnd = (HWND)widget->GetNativeData(NS_NATIVE_WINDOW);
        GetWindowThreadProcessId(hwnd, &pid);
      } else {
        MOZ_LOG(sWASLog, LogLevel::Debug, ("Failed to get widget"));
      }
    } else {
      MOZ_LOG(sWASLog, LogLevel::Debug, ("Failed to get navWin"));
    }
  } else {
    MOZ_LOG(sWASLog, LogLevel::Debug, ("Failed to get WinMediator"));
  }

  // Run pipe communication off the main thread to prevent UI jank from
  // blocking. Nothing relies on the COM server's response or that it has
  // responded at time of commit.
  NS_DispatchBackgroundTask(
      NS_NewRunnableFunction(
          "SignalComNotificationHandled background task",
          [pid, aWindowsTag = nsString{aWindowsTag}]() mutable {
            std::wstring pipeName = GetNotificationPipeName(aWindowsTag.get());

            nsAutoHandle pipe;
            pipe.own(CreateFileW(pipeName.c_str(), GENERIC_READ | GENERIC_WRITE,
                                 0, nullptr, OPEN_EXISTING,
                                 FILE_FLAG_OVERLAPPED, nullptr));
            if (pipe.get() == INVALID_HANDLE_VALUE) {
              MOZ_LOG(sWASLog, LogLevel::Error,
                      ("Unable to open notification server pipe."));
              return;
            }

            DWORD pipeFlags = PIPE_READMODE_MESSAGE;
            if (!SetNamedPipeHandleState(pipe.get(), &pipeFlags, nullptr,
                                         nullptr)) {
              MOZ_LOG(sWASLog, LogLevel::Error,
                      ("Error setting pipe handle state, error %lu",
                       GetLastError()));
              return;
            }

            // Pass our window's PID to the COM server receive
            // `SetForegroundWindow` permissions, and wait for a message
            // acknowledging the permission has been granted.
            ToastNotificationPidMessage in{};
            in.pid = pid;
            ToastNotificationPermissionMessage out{};
            auto transact = [&](OVERLAPPED& overlapped) {
              return TransactNamedPipe(pipe.get(), &in, sizeof(in), &out,
                                       sizeof(out), nullptr, &overlapped);
            };
            bool result =
                SyncDoOverlappedIOWithTimeout(pipe, sizeof(out), transact);

            if (result && out.setForegroundPermissionGranted && pid != 0) {
              MOZ_LOG(
                  sWASLog, LogLevel::Info,
                  ("SetForegroundWindow permission granted to our window."));
            } else {
              MOZ_LOG(sWASLog, LogLevel::Error,
                      ("SetForegroundWindow permission not granted to our "
                       "window."));
            }
          }),
      NS_DISPATCH_EVENT_MAY_BLOCK);
}

NS_IMETHODIMP
ToastNotification::HandleWindowsTag(const nsAString& aWindowsTag,
                                    JSContext* aCx, dom::Promise** aPromise) {
  NS_ENSURE_TRUE(mAumid.isSome(), NS_ERROR_UNEXPECTED);
  NS_ENSURE_TRUE(NS_IsMainThread(), NS_ERROR_NOT_SAME_THREAD);

  ErrorResult rv;
  RefPtr<dom::Promise> promise =
      dom::Promise::Create(xpc::CurrentNativeGlobal(aCx), rv);
  ENSURE_SUCCESS(rv, rv.StealNSResult());

  this->VerifyTagPresentOrFallback(aWindowsTag)
      ->Then(
          GetMainThreadSerialEventTarget(), __func__,
          [aWindowsTag = nsString(aWindowsTag),
           promise](const ToastHandledResolve& aResolved) {
            // We no longer need to query toast information from OS and can
            // allow the COM server to proceed (toast information is lost once
            // the COM server's `Activate` callback returns).
            SignalComNotificationHandled(aWindowsTag);

            dom::AutoJSAPI js;
            if (NS_WARN_IF(!js.Init(promise->GetGlobalObject()))) {
              promise->MaybeReject(NS_ERROR_FAILURE);
              return;
            }

            // Resolve the DOM Promise with a JS object. Set `launchUrl` and/or
            // `privilegedName` properties if fallback handling is necessary.

            JSContext* cx = js.cx();
            JS::Rooted<JSObject*> obj(cx, JS_NewPlainObject(cx));

            auto setProperty = [&](const char* name, const nsString& value) {
              JS::Rooted<JSString*> title(cx,
                                          JS_NewUCStringCopyZ(cx, value.get()));
              JS::Rooted<JS::Value> attVal(cx, JS::StringValue(title));
              Unused << NS_WARN_IF(!JS_SetProperty(cx, obj, name, attVal));
            };

            if (!aResolved.launchUrl.IsEmpty()) {
              setProperty("launchUrl", aResolved.launchUrl);
            }
            if (!aResolved.privilegedName.IsEmpty()) {
              setProperty("privilegedName", aResolved.privilegedName);
            }

            promise->MaybeResolve(obj);
          },
          [aWindowsTag = nsString(aWindowsTag), promise]() {
            // We no longer need to query toast information from OS and can
            // allow the COM server to proceed (toast information is lost once
            // the COM server's `Activate` callback returns).
            SignalComNotificationHandled(aWindowsTag);

            promise->MaybeReject(NS_ERROR_FAILURE);
          });

  promise.forget(aPromise);
  return NS_OK;
}

NS_IMETHODIMP
ToastNotification::CloseAlert(const nsAString& aAlertName,
                              bool aContextClosed) {
  RefPtr<ToastNotificationHandler> handler;
  if (NS_WARN_IF(!mActiveHandlers.Get(aAlertName, getter_AddRefs(handler)))) {
    return NS_OK;
  }

  if (!aContextClosed || handler->IsPrivate()) {
    // Hide the alert when not implicitly closed by tab/window closing or when
    // notification originated from a private tab.
    handler->HideAlert();
  }

  mActiveHandlers.Remove(aAlertName);
  handler->UnregisterHandler();

  return NS_OK;
}

bool ToastNotification::IsActiveHandler(const nsAString& aAlertName,
                                        ToastNotificationHandler* aHandler) {
  RefPtr<ToastNotificationHandler> handler;
  if (NS_WARN_IF(!mActiveHandlers.Get(aAlertName, getter_AddRefs(handler)))) {
    return false;
  }
  return handler == aHandler;
}

void ToastNotification::RemoveHandler(const nsAString& aAlertName,
                                      ToastNotificationHandler* aHandler) {
  // The alert may have been replaced; only remove it from the active
  // handler's map if it's the same.
  if (IsActiveHandler(aAlertName, aHandler)) {
    // Terrible things happen if the destructor of a handler is called inside
    // the hashtable .Remove() method. Wait until we have returned from there.
    RefPtr<ToastNotificationHandler> kungFuDeathGrip(aHandler);
    mActiveHandlers.Remove(aAlertName);
    aHandler->UnregisterHandler();
  }
}

NS_IMETHODIMP
ToastNotification::RemoveAllNotificationsForInstall() {
  HRESULT hr = S_OK;

  ComPtr<IToastNotificationManagerStatics> manager;
  hr = GetActivationFactory(
      HStringReference(
          RuntimeClass_Windows_UI_Notifications_ToastNotificationManager)
          .Get(),
      &manager);
  NS_ENSURE_TRUE(SUCCEEDED(hr), NS_ERROR_FAILURE);

  HString aumid;
  MOZ_ASSERT(mAumid.isSome());
  hr = aumid.Set(mAumid.ref().get());
  NS_ENSURE_TRUE(SUCCEEDED(hr), NS_ERROR_FAILURE);

  // Hide toasts in action center.
  [&]() {
    ComPtr<IToastNotificationManagerStatics2> manager2;
    hr = manager.As(&manager2);
    NS_ENSURE_TRUE_VOID(SUCCEEDED(hr));

    ComPtr<IToastNotificationHistory> history;
    hr = manager2->get_History(&history);
    NS_ENSURE_TRUE_VOID(SUCCEEDED(hr));

    hr = history->ClearWithId(aumid.Get());
    NS_ENSURE_TRUE_VOID(SUCCEEDED(hr));
  }();

  // Hide scheduled toasts.
  [&]() {
    ComPtr<IToastNotifier> notifier;
    hr = manager->CreateToastNotifierWithId(aumid.Get(), &notifier);
    NS_ENSURE_TRUE_VOID(SUCCEEDED(hr));

    ComPtr<IVectorView_ScheduledToastNotification> scheduledToasts;
    hr = notifier->GetScheduledToastNotifications(&scheduledToasts);
    NS_ENSURE_TRUE_VOID(SUCCEEDED(hr));

    unsigned int schedSize;
    hr = scheduledToasts->get_Size(&schedSize);
    NS_ENSURE_TRUE_VOID(SUCCEEDED(hr));

    for (unsigned int i = 0; i < schedSize; i++) {
      ComPtr<IScheduledToastNotification> schedToast;
      hr = scheduledToasts->GetAt(i, &schedToast);
      if (NS_WARN_IF(FAILED(hr))) {
        continue;
      }

      hr = notifier->RemoveFromSchedule(schedToast.Get());
      Unused << NS_WARN_IF(FAILED(hr));
    }
  }();

  return NS_OK;
}

}  // namespace widget
}  // namespace mozilla