/*
    Copyright (C) 2019 The Qt Company Ltd.
    Copyright (C) 2008, 2009, 2012 Nokia Corporation and/or its subsidiary(-ies)
    Copyright (C) 2007 Staikos Computing Services Inc.
    Copyright (C) 2007 Apple Inc.

    This library is free software; you can redistribute it and/or
    modify it under the terms of the GNU Library General Public
    License as published by the Free Software Foundation; either
    version 2 of the License, or (at your option) any later version.

    This library is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
    Library General Public License for more details.

    You should have received a copy of the GNU Library General Public License
    along with this library; see the file COPYING.LIB.  If not, write to
    the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
    Boston, MA 02110-1301, USA.
*/

// The documentation in this file was imported from QtWebKit and is thus constrained
// by its LGPL license. Documentation written from scratch for new methods should be
// placed inline in the code as usual.

/*!
    \class QWebEnginePage
    \brief The QWebEnginePage class provides an object to view and edit web documents.
    \since 5.4
    \inmodule QtWebEngineWidgets

    A \e {web engine page} holds the contents of an HTML document, the history of navigated
    links, and actions.

    QWebEnginePage's API is very similar to QWebEngineView, as you are still provided with
    common functions like action() (known as
    \l{QWebEngineView::pageAction()}{pageAction}() in QWebEngineView), triggerAction(),
    and findText().

    A page can be loaded using load() or setUrl(). Alternatively, if you have
    the HTML content readily available, you can use setHtml(). The GET method is
    always used to load URLs.

    The QWebEnginePage class also offers methods to retrieve both the URL currently
    loaded by the page (see url()) as well as the URL originally requested
    to be loaded (see requestedUrl()). These methods make possible the retrieval
    of the URL before and after a DNS resolution or a redirection occurs during
    the load process. The requestedUrl() also matches to the URL added to the
    page history (\l{QWebEngineHistory}) if load is successful.

    The title of an HTML page can be accessed with the title() property.
    Additionally, a page may also specify an icon, which can be accessed
    using the icon() or its URL using the iconUrl() property.
    If the title or the icon changes, the corresponding titleChanged(), iconChanged()
    and iconUrlChanged() signals will be emitted.
    The zoomFactor() property enables zooming the contents of the web page by a
    scale factor.

    The loadStarted() signal is emitted when the page begins to load, whereas the loadProgress()
    signal is emitted whenever an element of the web page completes loading, such as an embedded
    image or a script. The loadFinished() signal is emitted when the page contents
    have been loaded completely, independent of script execution or page rendering.
    Its argument, either \c true or \c false, indicates whether or not the load
    operation succeeded.

    An HTML document is loaded in a \e {main frame} within the web page. If it references
    \e {child frames} (as defined by the \c  <frame> or \c <iframe> elements), they are considered
    part of the content. Child frames are individually accessible only through JavaScript.

    Web sites define \e {security origin} for safely accessing each other's resources for
    client-side scripting or databases. An origin consist of a host name, a scheme, and a port
    number. For example, the sites \c http://www.example.com/my/page.html and
    \c http://www.example.com/my/overview.html are allowed to share the same database or access
    each other's documents when used in HTML frame sets and JavaScript. At the same time,
    \c http://www.malicious.com/evil.html is prevented from accessing the resources of
    \c http://www.example.com/, because they are of a different security origin.
    By default, local schemes like \c file:// and \c qrc:// are considered to be in the same
    security origin, and can access each other's resources. Local resources are by default
    restricted from accessing remote content, which means that \c file:// will not be able to
    access \c http://domain.com/foo.html.

    Scripts can be executed on the web page by using runJavaScript(), either in the main
    JavaScript \e world, along with the rest of the JavaScript coming from the web contents, or in
    their own isolated world. While the DOM of the page can be accessed from any world, JavaScript
    variables of a function defined in one world are not accessible from a different one.
    QWebEngineScript::ScriptWorldId provides some predefined IDs for this purpose. Using the
    \c runJavaScript() version without the world ID is the same as running the script in the
    \c MainWorld.

    The \l {QWebEngineSettings::FocusOnNavigationEnabled} {FocusOnNavigationEnabled} setting can be
    used to make the view associated with the page automatically receive focus when a navigation
    operation occurs (like loading or reloading a page or navigating through history).
*/

/*!
   \enum QWebEnginePage::FindFlag

   This enum describes the options available to the findText() function. The options
   can be OR-ed together from the following list:

   \value FindBackward Searches backwards instead of forwards.
   \value FindCaseSensitively By default findText() works case insensitive. Specifying this option
   changes the behavior to a case sensitive find operation.
*/

/*!
    \enum QWebEnginePage::WebAction

    This enum describes the types of action which can be performed on the web page.

    Actions only have an effect when they are applicable.

    The availability of actions can be be determined by checking
    \l{QAction::}{isEnabled()} on the action returned by action().

    \value NoWebAction No action is triggered.
    \value Back Navigate back in the history of navigated links.
    \value Forward Navigate forward in the history of navigated links.
    \value Stop Stop loading the current page.
    \value Reload Reload the current page.
    \value ReloadAndBypassCache Reload the current page, but do not use any local cache.
    \value Cut Cut the content currently selected into the clipboard.
    \value Copy Copy the content currently selected into the clipboard.
    \value Paste Paste content from the clipboard.
    \value Undo Undo the last editing action.
    \value Redo Redo the last editing action.
    \value SelectAll Select all content. This action is only enabled when the page's content is focused.
           The focus can be forced by the JavaScript \c{window.focus()} call, or the
           \l{QWebEngineSettings::FocusOnNavigationEnabled} {FocusOnNavigationEnabled} setting
           should be enabled to get automatic focus.
    \value PasteAndMatchStyle Paste content from the clipboard with current style.

    \value OpenLinkInThisWindow Open the current link in the current window. (Added in Qt 5.6)
    \value OpenLinkInNewWindow Open the current link in a new window. Requires implementation of
           \l createWindow(). (Added in Qt 5.6)
    \value OpenLinkInNewTab Open the current link in a new tab. Requires implementation of
           \l createWindow(). (Added in Qt 5.6)
    \value OpenLinkInNewBackgroundTab Open the current link in a new background tab. Requires
           implementation of \l createWindow(). (Added in Qt 5.7)
    \value CopyLinkToClipboard Copy the current link to the clipboard. (Added in Qt 5.6)

    \value CopyImageToClipboard Copy the clicked image to the clipboard. (Added in Qt 5.6)
    \value CopyImageUrlToClipboard Copy the clicked image's URL to the clipboard. (Added in Qt 5.6)
    \value CopyMediaUrlToClipboard Copy the hovered audio or video's URL to the clipboard. (Added in Qt 5.6)
    \value ToggleMediaControls Toggle between showing and hiding the controls for the hovered audio
           or video element. (Added in Qt 5.6)
    \value ToggleMediaLoop Toggle whether the hovered audio or video should loop on completetion or
           not. (Added in Qt 5.6)
    \value ToggleMediaPlayPause Toggle the play/pause state of the hovered audio or video element.
           (Added in Qt 5.6)
    \value ToggleMediaMute Mute or unmute the hovered audio or video element. (Added in Qt 5.6)
    \value DownloadLinkToDisk Download the current link to the disk. Requires a slot for
           \l{QWebEngineProfile::}{downloadRequested()}. (Added in Qt 5.6)
    \value DownloadImageToDisk Download the highlighted image to the disk. Requires a slot for
           \l{QWebEngineProfile::}{downloadRequested()}. (Added in Qt 5.6)
    \value DownloadMediaToDisk Download the hovered audio or video to the disk. Requires a slot for
           \l{QWebEngineProfile::}{downloadRequested()}. (Added in Qt 5.6)

    \value InspectElement Trigger any attached Web Inspector to inspect the highlighed element.
           (Added in Qt 5.6)
    \value ExitFullScreen Exit the fullscreen mode. (Added in Qt 5.6)
    \value RequestClose Request to close the web page. If defined, the \c{window.onbeforeunload}
           handler is run, and the user can confirm or reject to close the page. If the close
           request is confirmed, \c windowCloseRequested is emitted. (Added in Qt 5.6)
    \value Unselect Clear the current selection. (Added in Qt 5.7)
    \value SavePage Save the current page to disk. MHTML is the default format that is used to store
           the web page on disk. Requires a slot for \l{QWebEngineProfile::}{downloadRequested()}.
           (Added in Qt 5.7)
    \value ViewSource Show the source of the current page in a new tab. Requires implementation of
            \l createWindow(). (Added in Qt 5.8)

    \value ToggleBold
           Toggles boldness for the selection or at the cursor position.
           Requires \c contenteditable="true". (Added in Qt 5.10)
    \value ToggleItalic
           Toggles italics for the selection or at the cursor position.
           Requires \c contenteditable="true". (Added in Qt 5.10)
    \value ToggleUnderline
           Toggles underlining of the selection or at the cursor position.
           Requires \c contenteditable="true". (Added in Qt 5.10)
    \value ToggleStrikethrough
           Toggles striking through the selection or at the cursor position.
           Requires \c contenteditable="true". (Added in Qt 5.10)

    \value AlignLeft
           Aligns the lines containing the selection or the cursor to the left.
           Requires \c contenteditable="true". (Added in Qt 5.10)
    \value AlignCenter
           Aligns the lines containing the selection or the cursor at the center.
           Requires \c contenteditable="true". (Added in Qt 5.10)
    \value AlignRight
           Aligns the lines containing the selection or the cursor to the right.
           Requires \c contenteditable="true". (Added in Qt 5.10)
    \value AlignJustified
           Stretches the lines containing the selection or the cursor so that each
           line has equal width.
           Requires \c contenteditable="true". (Added in Qt 5.10)
    \value Indent
           Indents the lines containing the selection or the cursor.
           Requires \c contenteditable="true". (Added in Qt 5.10)
    \value Outdent
           Outdents the lines containing the selection or the cursor.
           Requires \c contenteditable="true". (Added in Qt 5.10)

    \value InsertOrderedList
           Inserts an ordered list at the current cursor position, deleting the current selection.
           Requires \c contenteditable="true". (Added in Qt 5.10)
    \value InsertUnorderedList
           Inserts an unordered list at the current cursor position,
           deleting the current selection.
           Requires \c contenteditable="true". (Added in Qt 5.10)
    \omitvalue WebActionCount

*/

/*!
    \enum QWebEnginePage::WebWindowType

    This enum describes the types of window that can be created by the createWindow() function:

    \value  WebBrowserWindow
            A complete web browser window.
    \value  WebBrowserTab
            A web browser tab.
    \value  WebDialog
            A window without decoration.
    \value  WebBrowserBackgroundTab
            A web browser tab without hiding the current visible WebEngineView. (Added in Qt 5.7)
*/

/*!
    \enum QWebEnginePage::JavaScriptConsoleMessageLevel

    This enum describes the different severity levels a JavaScript console message can have:

    \value InfoMessageLevel The message is purely informative and can safely be ignored.
    \value WarningMessageLevel The message informs about unexpected behavior or errors that may
           need attention.
    \value ErrorMessageLevel The message indicates there has been an error.
*/

/*!
    \enum QWebEnginePage::FileSelectionMode

    This enum indicates whether the implementation of the chooseFiles() function should
    return only one file or may return multiple files:

    \value  FileSelectOpen
            Return only one file name.
    \value  FileSelectOpenMultiple
            Return multiple file names.

    \sa chooseFiles()
*/

/*!
    \enum QWebEnginePage::PermissionPolicy

    This enum describes the permission policies that the user may set for data or device access:

    \value PermissionUnknown It is unknown whether the user grants or denies permission.
    \value PermissionGrantedByUser The user has granted permission.
    \value PermissionDeniedByUser The user has denied permission.

    \sa featurePermissionRequested(), featurePermissionRequestCanceled(), setFeaturePermission(), Feature
*/

/*!
    \enum QWebEnginePage::NavigationType

    This enum describes the type of a navigation request:

    \value NavigationTypeLinkClicked The navigation request resulted from a clicked link.
    \value NavigationTypeTyped The navigation request resulted from an explicitly loaded URL.
    \value NavigationTypeFormSubmitted The navigation request resulted from a form submission.
    \value NavigationTypeBackForward The navigation request resulted from a back or forward action.
    \value NavigationTypeReload The navigation request resulted from a reload action.
    \value NavigationTypeRedirect The navigation request resulted from a content or server controlled redirect. This also includes automatic reloads. (Added in Qt 5.14)
    \value NavigationTypeOther The navigation request was triggered by other means not covered by the above.

    \sa acceptNavigationRequest()
*/

/*!
    \enum QWebEnginePage::Feature

    This enum describes the platform feature access categories that the user may be asked to grant
    or deny access to:

    \value  Notifications
            Web notifications for the end-user.
    \value  Geolocation
            Location hardware or service.
    \value  MediaAudioCapture
            Audio capture devices, such as microphones.
    \value  MediaVideoCapture
            Video devices, such as cameras.
    \value  MediaAudioVideoCapture
            Both audio and video capture devices.
    \value  MouseLock
            Mouse locking, which locks the mouse pointer to the web view and is typically used in
            games.
    \value  DesktopVideoCapture
            Video output capture, that is, the capture of the user's display,
            for screen sharing purposes for example. (Added in Qt 5.10)
    \value  DesktopAudioVideoCapture
            Both audio and video output capture. (Added in Qt 5.10)

    \sa featurePermissionRequested(), featurePermissionRequestCanceled(), setFeaturePermission(), PermissionPolicy

*/

/*!
    \fn QWebEnginePage::QWebEnginePage(QObject *parent)
    Constructs an empty QWebEnginePage with the parent \a parent.
*/

/*!
    \fn QWebEnginePage::~QWebEnginePage()
    Destroys the web page.
*/

/*!
    \fn QWebEngineHistory *QWebEnginePage::history() const
    Returns a pointer to the view's history of navigated web pages.
*/

/*!
    \fn void QWebEnginePage::setView(QWidget* view)
    Sets the \a view that is associated with the web page.

    \sa view()
*/

/*!
    \fn QWidget *QWebEnginePage::view() const
    Returns the view widget that is associated with the web page.

    \sa setView()
*/

/*!
    \fn QMenu *QWebEnginePage::createStandardContextMenu()
    Creates the standard context menu which is shown when
    the user clicks on the web page with the right mouse button. It is
    called from the default \l{QWidget::}{contextMenuEvent()} handler. The popup menu's
    ownership is transferred to the caller.

    Returns \c nullptr if the context menu data is not initialized, for example when it
    is called when there is actually no context menu requested.
 */

/*!
    \fn void QWebEnginePage::javaScriptConsoleMessage(JavaScriptConsoleMessageLevel level, const QString& message, int lineNumber, const QString& sourceID)
    This function is called when a JavaScript program tries to print the \a message to the web
    browser's console.

    For example, in case of evaluation errors the source URL may be provided in \a sourceID as well
    as the \a lineNumber.

    \a level indicates the severity of the event that triggered the message. That is, whether it
    was triggered by an error or a less severe event.

    Since Qt 5.6, the default implementation logs the messages in a \c js
    \l{QLoggingCategory}{logging category}.

    \sa{Console Logging}
*/

/*!
    \fn bool QWebEnginePage::acceptNavigationRequest(const QUrl &url, NavigationType type, bool isMainFrame)
    \since 5.5
    This function is called upon receiving a request to navigate to the specified \a url by means of
    the specified navigation type \a type. \a isMainFrame indicates whether the request corresponds
    to the main frame or a child frame. If the function returns \c true, the navigation request is
    accepted and \c url is loaded. The default implementation accepts all navigation requests.

    Navigation requests can be delegated to the Qt application instead of having the HTML handler
    engine process them by overloading this function. This is necessary when an HTML document is
    used as part of the user interface, and not to display external data, for example, when
    displaying a list of results.

    \note This function is not called for fragment navigation on the same page. Such navigation,
    for example, happens by clicking a link to a '#fragment' within the page. It does not trigger
    a load to a different document, even though it changes page's url and adds history entry.
    It only serves as a shortcut to scroll within the page. Hence, no delegation of this navigation
    type is expected to happen.

    \note The loading process is started and the loadStarted() signal is emitted
    \e before the request is accepted or rejected. Therefore, a loadFinished()
    signal that returns \c false is to be expected even after delegating the
    request.

    \note When using setHtml or setContent with relative links, make
    sure to specify a base url, otherwise the links will be considered
    invalid and no navigation requests will be emitted.

    The \l{QWebEngineUrlRequestInterceptor} class offers further options for intercepting and
    manipulating requests.
*/

/*!
    \fn void QWebEnginePage::javaScriptAlert(const QUrl &securityOrigin, const QString& msg)
    This function is called whenever a JavaScript program running in a frame affiliated with
    \a securityOrigin calls the \c alert() function with the message \a msg.

    The default implementation shows the message, \a msg, with QMessageBox::information.
*/

/*!
    \fn bool QWebEnginePage::javaScriptConfirm(const QUrl &securityOrigin, const QString& msg)
    This function is called whenever a JavaScript program running in a frame affiliated with
    \a securityOrigin calls the \c confirm() function with the message \a msg. Returns \c true
    if the user confirms the message; otherwise returns \c false.

    It is also called when the \c onbeforeunload handler is requesting a confirmation before
    leaving a page.

    The default implementation executes the query using QMessageBox::information with QMessageBox::Ok and QMessageBox::Cancel buttons.
*/

/*!
    \fn bool QWebEnginePage::javaScriptPrompt(const QUrl &securityOrigin, const QString& msg, const QString& defaultValue, QString* result)
    This function is called whenever a JavaScript program running in a frame affiliated with \a securityOrigin tries to prompt the user for input.
    The program may provide an optional message, \a msg, as well as a default value for the input in \a defaultValue.

    If the prompt was cancelled by the user, the implementation should return \c false; otherwise the
    result should be written to \a result and \c true should be returned. If the prompt was not
    cancelled by the user, the implementation should return \c true and the result string must not
    be null.

    The default implementation uses QInputDialog::getText().
*/

/*!
    \fn QWebEnginePage *QWebEnginePage::createWindow(WebWindowType type)
    This function is called to create a new window of the specified \a type. For example, when a
    JavaScript program requests to open a document in a new window.

    If the new window can be created, the new window's QWebEnginePage is returned; otherwise a null pointer is returned.

    If the view associated with the web page is a QWebEngineView object, then the default implementation forwards
    the request to QWebEngineView::createWindow(); otherwise it returns a null pointer.

    \note In the cases when the window creation is being triggered by JavaScript, apart from
    reimplementing this method the application must also set
    QWebEngineSettings::JavascriptCanOpenWindows to \c true in order for the method to get called.

    \sa QWebEngineView::createWindow()
*/

/*!
    \fn void QWebEnginePage::triggerAction(WebAction action, bool checked = false)
    This function can be called to trigger the specified \a action.
    It is also called by \QWE if the user triggers the action, for example
    through a context menu item.

    If \a action is a checkable action, then \a checked specifies whether the action
    is toggled or not.

    \sa action()
*/

/*!
    \property QWebEnginePage::hasSelection
    \brief Whether this page contains selected content or not.

    \sa selectionChanged()
*/

/*!
    \property QWebEnginePage::selectedText
    \brief The text currently selected.

    By default, this property contains an empty string.

    \sa selectionChanged()
*/

/*!
    \fn QAction *QWebEnginePage::action(WebAction action) const
    Returns a QAction for the specified WebAction \a action.

    The action is owned by the QWebEnginePage but you can customize the look by
    changing its properties.

    QWebEnginePage also takes care of implementing the action, so that upon
    triggering the corresponding action is performed on the page.

    \sa triggerAction()
*/

/*!
    \fn void QWebEnginePage::findText(const QString &subString, QWebEnginePage::FindFlags options = FindFlags(), const QWebEngineCallback<bool> &resultCallback = QWebEngineCallback<bool>())
    Finds the specified string, \a subString, in the page, using the given \a options.
    The findTextFinished() signal is emitted when a string search is completed.

    To clear the search highlight, just pass an empty string.

    The \a resultCallback must take a boolean parameter. It will be called with a value of \c true
    if the \a subString was found; otherwise the callback value will be \c false.

    \warning We guarantee that the callback (\a resultCallback) is always called, but it might be done
    during page destruction. When QWebEnginePage is deleted, the callback is triggered with an invalid
    value and it is not safe to use the corresponding QWebEnginePage or QWebEngineView instance inside it.

    For example:
    \snippet qtwebengine_qwebenginepage_snippet.cpp 0

    \sa findTextFinished()
*/

/*!
    \fn QWebEngineSettings *QWebEnginePage::settings() const
    Returns a pointer to the page's settings object.

    \sa QWebEngineSettings::defaultSettings()
*/

/*!
    \fn bool QWebEnginePage::certificateError(const QWebEngineCertificateError & certificateError)
    This function is called when an invalid certificate error is raised while loading a given request.

    The \a certificateError parameter contains information about the certificate and details of the error.

    Return \c true to ignore the error and complete the request. Return \c false to stop loading
    the request.

    \note If the error was successfully deferred then the returned value will be ignored.

    \sa QWebEngineCertificateError
*/

/*!
    \fn QString QWebEnginePage::chooseFiles(FileSelectionMode mode, const QStringList& oldFiles, const QStringList& acceptedMimeTypes)
    This function is called when the web content requests a file name, for example
    as a result of the user clicking on a file upload button in an HTML form.

    \a mode indicates whether only one file or multiple files are expected to be returned.

    A suggested filename may be provided as the first entry of \a oldFiles. \a acceptedMimeTypes is ignored by the default implementation,
    but might be used by overrides.
*/

/*!
    \fn void QWebEnginePage::loadStarted()

    This signal is emitted when a page starts loading content.

    \sa loadFinished(), acceptNavigationRequest()
*/

/*!
    \fn void QWebEnginePage::loadProgress(int progress)

    This signal is emitted when the global progress status changes.
    The current value is provided by \a progress and scales from 0 to 100,
    which is the default range of QProgressBar.
    It accumulates changes from all the child frames.

*/

/*!
    \fn void QWebEnginePage::loadFinished(bool ok)

    This signal is emitted when the page finishes loading content. This signal
    is independent of script execution or page rendering.
    \a ok will indicate whether the load was successful or any error occurred.

    \note Navigation requests can be delegated to the Qt application instead
    of having the HTML handler engine process them by overloading the
    acceptNavigationRequest() function. Because the loading process is started
    and the loadStarted() signal is emitted \e before the request is accepted
    or rejected, a \c loadFinished() signal that returns \c false is to be
    expected even after delegating the request.

    \sa loadStarted(), acceptNavigationRequest()
*/

/*!
    \fn void QWebEnginePage::selectionChanged()

    This signal is emitted whenever the selection changes, either interactively
    or programmatically. For example, by calling triggerAction() with a selection action.

    \note When using the mouse to select text by left-clicking and dragging, the signal will be
    emitted for each new character selected, and not upon releasing the left mouse button.

    \sa selectedText()
*/

/*!
    \fn void QWebEnginePage::linkHovered(const QString &url)

    This signal is emitted when the mouse hovers over a link.
    \a url contains the target URL of the link.
*/

/*!

    \fn void QWebEnginePage::authenticationRequired(const QUrl &requestUrl, QAuthenticator *authenticator)

    This signal is emitted when access to \a requestUrl requires authentication.
    \a authenticator should be used to pass the user name and password for the connection.
*/

/*!
    \fn void QWebEnginePage::proxyAuthenticationRequired(const QUrl &requestUrl, QAuthenticator *authenticator, const QString &proxyHost)

    This signal is emitted when access to \a requestUrl via \a proxyHost requires authentication for the proxy.
    \a authenticator should be used to pass the user name and password for the connection.

*/

/*!
    \fn void QWebEnginePage::geometryChangeRequested(const QRect& geom)

    This signal is emitted whenever the document wants to change the position and size of the
    page to \a geom. This can happen for example through JavaScript.

    \note \l{QWindow::}{setGeometry()} expects a size excluding the window
    decoration, while \a geom includes it. You have to remove the size of the frame margins
    from \a geom to handle this signal correctly.

    \code
    window->setGeometry(geom.marginsRemoved(window->frameMargins()));
    \endcode
*/

/*!
    \fn void QWebEnginePage::windowCloseRequested()

    This signal is emitted whenever the page requests the web browser window to be closed,
    for example through the JavaScript \c{window.close()} call.

    \sa RequestClose
*/

/*!
    \fn void QWebEnginePage::toHtml(const QWebEngineCallback<const QString &> &resultCallback) const
    Asynchronous method to retrieve the page's content as HTML, enclosed in HTML and BODY tags.
    Upon successful completion, \a resultCallback is called with the page's content.

    \note \a resultCallback can be any of a function pointer, a functor or a lambda, and it is expected to take a QString parameter.

    \warning We guarantee that the callback (\a resultCallback) is always called, but it might be done
    during page destruction. When QWebEnginePage is deleted, the callback is triggered with an invalid
    value and it is not safe to use the corresponding QWebEnginePage or QWebEngineView instance inside it.

    \sa setHtml(), toPlainText()
*/

/*!
    \fn void QWebEnginePage::toPlainText(const QWebEngineCallback<const QString &> &resultCallback) const
    Asynchronous method to retrieve the page's content converted to plain text, completely stripped of all
    HTML formatting.
    Upon successful completion, \a resultCallback is called with the page's content.

    \note \a resultCallback can be any of a function pointer, a functor or a lambda, and it is expected to take a QString parameter.

    \warning We guarantee that the callback (\a resultCallback) is always called, but it might be done
    during page destruction. When QWebEnginePage is deleted, the callback is triggered with an invalid
    value and it is not safe to use the corresponding QWebEnginePage or QWebEngineView instance inside it.

    \sa toHtml()
*/

/*!
    \property QWebEnginePage::title
    \brief The title of the page as defined by the HTML \c <title> element.

    If the page has no \c <title> element, then the URL is used instead. For \c
    file:// URLs only the filename is used and not the full path.

    By default, before any content has been loaded, this property contains an
    empty string.

    \sa titleChanged()
*/

/*!
    \property QWebEnginePage::url
    \brief The URL of the page currently viewed.

    Setting this property clears the view and loads the URL.

    By default, this property contains an empty, invalid URL.

    \sa urlChanged()
*/

/*!
    \property QWebEnginePage::requestedUrl
    \brief The URL that was originally requested to be loaded by the page
    that is currently viewed.

    \note The URL may differ from the one returned by url(), which is the actual
    URL that results from DNS resolution or redirection.

    \sa url(), setUrl()
*/

/*!
    \fn void QWebEnginePage::load(const QUrl &url)
    Loads \a url into this page.

    \note The view remains the same until enough data has arrived to display the new URL.

    \sa setUrl(), setHtml(), setContent()
*/

/*!
    \fn void QWebEnginePage::setHtml(const QString &html, const QUrl &baseUrl)
    Sets the content of this page to \a html. \a baseUrl is optional and used to resolve relative
    URLs in the document, such as referenced images or stylesheets.

    The \a html is loaded immediately; external objects are loaded asynchronously.

    If a script in the \a html runs longer than the default script timeout (currently 10 seconds),
    for example due to being blocked by a modal JavaScript alert dialog, this method will return
    as soon as possible after the timeout and any subsequent \a html will be loaded asynchronously.

    When using this method, the web engine assumes that external resources, such as JavaScript programs or style
    sheets, are encoded in UTF-8 unless otherwise specified. For example, the encoding of an external
    script can be specified through the charset attribute of the HTML script tag. It is also possible
    for the encoding to be specified by the web server.

    This is a convenience function equivalent to setContent(html, "text/html", baseUrl).

    \note This method will not affect session or global history for the page.

    \warning This function works only for HTML, for other mime types (such as XHTML and SVG)
    setContent() should be used instead.

    \warning The content will be percent encoded before being sent to the renderer via IPC.
    This may increase its size. The maximum size of the percent encoded content is
    2 megabytes minus 30 bytes.

    \sa toHtml(), setContent(), load()
*/

/*!
    \fn void QWebEnginePage::setContent(const QByteArray &data, const QString &mimeType, const QUrl &baseUrl)
    Sets the content of the web page to \a data. If the \a mimeType argument
    is empty, it is assumed that the content is \c{text/plain,charset=US-ASCII}.

    External objects referenced in the content are located relative to \a baseUrl.

    The \a data is loaded immediately; external objects are loaded asynchronously.

    \note This method will not affect session or global history for the page.

    \warning The content will be percent encoded before being sent to the renderer via IPC.
    This may increase its size. The maximum size of the percent encoded content is
    2 megabytes minus 6 bytes plus the length of the mime type string.

    \sa toHtml(), setHtml()
*/

/*!
    \property QWebEnginePage::zoomFactor
    \brief The zoom factor for the page content.

    Valid values are within the range from \c{0.25} to \c{5.0}. The default factor is \c{1.0}.
*/

/*!
    \fn void QWebEnginePage::runJavaScript(const QString &scriptSource, quint32 worldId, const QWebEngineCallback<const QVariant &> &resultCallback)
    \fn void QWebEnginePage::runJavaScript(const QString &scriptSource, quint32 worldId)
    \fn void QWebEnginePage::runJavaScript(const QString& scriptSource)
    \fn void QWebEnginePage::runJavaScript(const QString &scriptSource, const QWebEngineCallback<const QVariant &> &resultCallback)
    \since 5.7

    Runs the JavaScript code contained in \a scriptSource without checking
    whether the DOM of the page has been constructed. If you need more
    control over how the script is run, consider using \l scripts() instead.

    To avoid conflicts with other scripts executed on the page, the world in
    which the script is run is specified by \a worldId. The world ID values are
    the same as provided by QWebEngineScript::ScriptWorldId, and between \c 0
    and \c 256. If you leave out the \c world ID, the script is run in the
    \c MainWorld.

    When the script has been executed, \a resultCallback is called with the result of the last
    executed statement. \c resultCallback can be any of a function pointer, a functor or a lambda,
    and it is expected to take a QVariant parameter. For example:

    \code
    page.runJavaScript("document.title", [](const QVariant &v) { qDebug() << v.toString(); });
    \endcode

    Only plain data can be returned from JavaScript as the result value.
    Supported data types include all of the JSON data types as well as, for
    example, \c{Date} and \c{ArrayBuffer}. Unsupported data types include, for
    example, \c{Function} and \c{Promise}.

    \warning Do not execute lengthy routines in the callback function, because it might block the
    rendering of the web engine page.

    \warning We guarantee that the callback (\a resultCallback) is always called, but it might be done
    during page destruction. When QWebEnginePage is deleted, the callback is triggered with an invalid
    value and it is not safe to use the corresponding QWebEnginePage or QWebEngineView instance inside it.

    \sa scripts(), QWebEngineScript::ScriptWorldId, {Script Injection}
*/

/*!
    \fn void QWebEnginePage::setFeaturePermission(const QUrl &securityOrigin, Feature feature, PermissionPolicy policy)

    Sets the permission for the web site identified by \a securityOrigin to use \a feature to \a policy.

    \note This method is primarily for calling after a featurePermissionRequested() signal has been emitted
    to trigger the feature permission response. It can also be called before a request has been emitted,
    but will only set a granted permission for passive checks, mainly for Notification APIs that can check
    if permission has already been granted before explicitly requesting it.

    \sa featurePermissionRequested(), featurePermissionRequestCanceled()
*/

/*!
    \fn void QWebEnginePage::featurePermissionRequested(const QUrl &securityOrigin, Feature feature)

    This signal is emitted when the web site identified by \a securityOrigin requests to make use of
    the resource or device identified by \a feature.

    \sa featurePermissionRequestCanceled(), setFeaturePermission()
*/

/*!
    \fn void QWebEnginePage::featurePermissionRequestCanceled(const QUrl &securityOrigin, Feature feature)

    This signal is emitted when the web site identified by \a securityOrigin cancels a previously issued
    request to make use of \a feature.

    \sa featurePermissionRequested(), setFeaturePermission()

*/

/*!
    \fn void QWebEnginePage::titleChanged(const QString &title)

    This signal is emitted whenever the title of the page changes.
    The \a title string specifies the new title.

    \sa title()
*/

/*!
    \fn void QWebEnginePage::urlChanged(const QUrl &url)

    This signal is emitted with the URL of the page when the page title is
    received. The new URL is specified by \a url.

    \sa url()
*/
