equest' ) || 'request-completed' !== $request_data->status ) {
		return;
	}

	$already_notified = (bool) get_post_meta( $request_id, '_wp_user_notified', true );

	if ( $already_notified ) {
		return;
	}

	/**
	 * Filters the recipient of the data erasure fulfillment notification.
	 *
	 * @since 4.9.6
	 *
	 * @param string          $user_email   The email address of the notification recipient.
	 * @param WP_User_Request $request_data The request that is initiating the notification.
	 */
	$user_email = apply_filters( 'user_erasure_fulfillment_email_to', $request_data->email, $request_data );

	$email_data = array(
		'request'            => $request_data,
		'message_recipient'  => $user_email,
		'privacy_policy_url' => get_privacy_policy_url(),
		'sitename'           => wp_specialchars_decode( get_option( 'blogname' ), ENT_QUOTES ),
		'siteurl'            => home_url(),
	);

	$subject  = sprintf(
		/* translators: %s: Site name. */
		__( '[%s] Erasure Request Fulfilled' ),
		$email_data['sitename']
	);

	/**
	 * Filters the subject of the email sent when an erasure request is completed.
	 *
	 * @since 4.9.8
	 *
	 * @param string $subject    The email subject.
	 * @param string $sitename   The name of the site.
	 * @param array  $email_data {
	 *     Data relating to the account action email.
	 *
	 *     @type WP_User_Request $request            User request object.
	 *     @type string          $message_recipient  The address that the email will be sent to. Defaults
	 *                                               to the value of `$request->email`, but can be changed
	 *                                               by the `user_erasure_fulfillment_email_to` filter.
	 *     @type string          $privacy_policy_url Privacy policy URL.
	 *     @type string          $sitename           The site name sending the mail.
	 *     @type string          $siteurl            The site URL sending the mail.
	 * }
	 */
	$subject = apply_filters( 'user_erasure_complete_email_subject', $subject, $email_data['sitename'], $email_data );

	if ( empty( $email_data['privacy_policy_url'] ) ) {
		/* translators: Do not translate SITENAME, SITEURL; those are placeholders. */
		$email_text = __(
			'Howdy,

Your request to erase your personal data on ###SITENAME### has been completed.

If you have any follow-up questions or concerns, please contact the site administrator.

Regards,
All at ###SITENAME###
###SITEURL###'
		);
	} else {
		/* translators: Do not translate SITENAME, SITEURL, PRIVACY_POLICY_URL; those are placeholders. */
		$email_text = __(
			'Howdy,

Your request to erase your personal data on ###SITENAME### has been completed.

If you have any follow-up questions or concerns, please contact the site administrator.

For more information, you can also read our privacy policy: ###PRIVACY_POLICY_URL###

Regards,
All at ###SITENAME###
###SITEURL###'
		);
	}

	/**
	 * Filters the body of the data erasure fulfillment notification.
	 *
	 * The email is sent to a user when a their data erasure request is fulfilled
	 * by an administrator.
	 *
	 * The following strings have a special meaning and will get replaced dynamically:
	 *
	 * ###SITENAME###           The name of the site.
	 * ###PRIVACY_POLICY_URL### Privacy policy page URL.
	 * ###SITEURL###            The URL to the site.
	 *
	 * @since 4.9.6
	 *
	 * @param string $email_text Text in the email.
	 * @param array  $email_data {
	 *     Data relating to the account action email.
	 *
	 *     @type WP_User_Request $request            User request object.
	 *     @type string          $message_recipient  The address that the email will be sent to. Defaults
	 *                                               to the value of `$request->email`, but can be changed
	 *                                               by the `user_erasure_fulfillment_email_to` filter.
	 *     @type string          $privacy_policy_url Privacy policy URL.
	 *     @type string          $sitename           The site name sending the mail.
	 *     @type string          $siteurl            The site URL sending the mail.
	 * }
	 */
	$content = apply_filters( 'user_confirmed_action_email_content', $email_text, $email_data );

	$content = str_replace( '###SITENAME###', $email_data['sitename'], $content );
	$content = str_replace( '###PRIVACY_POLICY_URL###', $email_data['privacy_policy_url'], $content );
	$content = str_replace( '###SITEURL###', esc_url_raw( $email_data['siteurl'] ), $content );

	$email_sent = wp_mail( $user_email, $subject, $content );

	if ( $email_sent ) {
		update_post_meta( $request_id, '_wp_user_notified', true );
	}
}

/**
 * Return request confirmation message HTML.
 *
 * @since 4.9.6
 * @access private
 *
 * @param int $request_id The request ID being confirmed.
 * @return string $message The confirmation message.
 */
function _wp_privacy_account_request_confirmed_message( $request_id ) {
	$request = wp_get_user_request_data( $request_id );

	$message = '<p class="success">' . __( 'Action has been confirmed.' ) . '</p>';
	$message .= '<p>' . __( 'The site administrator has been notified and will fulfill your request as soon as possible.' ) . '</p>';

	if ( $request && in_array( $request->action_name, _wp_privacy_action_request_types(), true ) ) {
		if ( 'export_personal_data' === $request->action_name ) {
			$message = '<p class="success">' . __( 'Thanks for confirming your export request.' ) . '</p>';
			$message .= '<p>' . __( 'The site administrator has been notified. You will receive a link to download your export via email when they fulfill your request.' ) . '</p>';
		} elseif ( 'remove_personal_data' === $request->action_name ) {
			$message = '<p class="success">' . __( 'Thanks for confirming your erasure request.' ) . '</p>';
			$message .= '<p>' . __( 'The site administrator has been notified. You will receive an email confirmation when they erase your data.' ) . '</p>';
		}
	}

	/**
	 * Filters the message displayed to a user when they confirm a data request.
	 *
	 * @since 4.9.6
	 *
	 * @param string $message    The message to the user.
	 * @param int    $request_id The ID of the request being confirmed.
	 */
	$message = apply_filters( 'user_request_action_confirmed_message', $message, $request_id );

	return $message;
}

/**
 * Create and log a user request to perform a specific action.
 *
 * Requests are stored inside a post type named `user_request` since they can apply to both
 * users on the site, or guests without a user account.
 *
 * @since 4.9.6
 *
 * @param string $email_address User email address. This can be the address of a registered or non-registered user.
 * @param string $action_name   Name of the action that is being confirmed. Required.
 * @param array  $request_data  Misc data you want to send with the verification request and pass to the actions once the request is confirmed.
 * @return int|WP_Error Returns the request ID if successful, or a WP_Error object on failure.
 */
function wp_create_user_request( $email_address = '', $action_name = '', $request_data = array() ) {
	$email_address = sanitize_email( $email_address );
	$action_name   = sanitize_key( $action_name );

	if ( ! is_email( $email_address ) ) {
		return new WP_Error( 'invalid_email', __( 'Invalid email address.' ) );
	}

	if ( ! $action_name ) {
		return new WP_Error( 'invalid_action', __( 'Invalid action name.' ) );
	}

	$user    = get_user_by( 'email', $email_address );
	$user_id = $user && ! is_wp_error( $user ) ? $user->ID : 0;

	// Check for duplicates.
	$requests_query = new WP_Query( array(
		'post_type'     => 'user_request',
		'post_name__in' => array( $action_name ),  // Action name stored in post_name column.
		'title'         => $email_address, // Email address stored in post_title column.
		'post_status'   => 'any',
		'fields'        => 'ids',
	) );

	if ( $requests_query->found_posts ) {
		return new WP_Error( 'duplicate_request', __( 'A request for this email address already exists.' ) );
	}

	$request_id = wp_insert_post( array(
		'post_author'   => $user_id,
		'post_name'     => $action_name,
		'post_title'    => $email_address,
		'post_content'  => wp_json_encode( $request_data ),
		'post_status'   => 'request-pending',
		'post_type'     => 'user_request',
		'post_date'     => current_time( 'mysql', false ),
		'post_date_gmt' => current_time( 'mysql', true ),
	), true );

	return $request_id;
}

/**
 * Get action description from the name and return a string.
 *
 * @since 4.9.6
 *
 * @param string $action_name Action name of the request.
 * @return string Human readable action name.
 */
function wp_user_request_action_description( $action_name ) {
	switch ( $action_name ) {
		case 'export_personal_data':
			$description = __( 'Export Personal Data' );
			break;
		case 'remove_personal_data':
			$description = __( 'Erase Personal Data' );
			break;
		default:
			/* translators: %s: action name */
			$description = sprintf( __( 'Confirm the "%s" action' ), $action_name );
			break;
	}

	/**
	 * Filters the user action description.
	 *
	 * @since 4.9.6
	 *
	 * @param string $description The default description.
	 * @param string $action_name The name of the request.
	 */
	return apply_filters( 'user_request_action_description', $description, $action_name );
}

/**
 * Send a confirmation request email to confirm an action.
 *
 * If the request is not already pending, it will be updated.
 *
 * @since 4.9.6
 *
 * @param string $request_id ID of the request created via wp_create_user_request().
 * @return WP_Error|bool Will return true/false based on the success of sending the email, or a WP_Error object.
 */
function wp_send_user_request( $request_id ) {
	$request_id = absint( $request_id );
	$request    = wp_get_user_request_data( $request_id );

	if ( ! $request ) {
		return new WP_Error( 'user_request_error', __( 'Invalid request.' ) );
	}

	$email_data = array(
		'request'     => $request,
		'email'       => $request->email,
		'description' => wp_user_request_action_description( $request->action_name ),
		'confirm_url' => add_query_arg( array(
			'action'      => 'confirmaction',
			'request_id'  => $request_id,
			'confirm_key' => wp_generate_user_request_key( $request_id ),
		), wp_login_url() ),
		'sitename'    => wp_specialchars_decode( get_option( 'blogname' ), ENT_QUOTES ),
		'siteurl'     => home_url(),
	);

	/* translators: Do not translate DESCRIPTION, CONFIRM_URL, SITENAME, SITEURL: those are placeholders. */
	$email_text = __(
		'Howdy,

A request has been made to perform the following action on your account:

     ###DESCRIPTION###

To confirm this, please click on the following link:
###CONFIRM_URL###

You can safely ignore and delete this email if you do not want to
take this action.

Regards,
All at ###SITENAME###
###SITEURL###'
	);

	/**
	 * Filters the text of the email sent when an account action is attempted.
	 *
	 * The following strings have a special meaning and will get replaced dynamically:
	 *
	 * ###DESCRIPTION### Description of the action being performed so the user knows what the email is for.
	 * ###CONFIRM_URL### The link to click on to confirm the account action.
	 * ###SITENAME###    The name of the site.
	 * ###SITEURL###     The URL to the site.
	 *
	 * @since 4.9.6
	 *
	 * @param string $email_text Text in the email.
	 * @param array  $email_data {
	 *     Data relating to the account action email.
	 *
	 *     @type WP_User_Request $request     User request object.
	 *     @type string          $email       The email address this is being sent to.
	 *     @type string          $description Description of the action being performed so the user knows what the email is for.
	 *     @type string          $confirm_url The link to click on to confirm the account action.
	 *     @type string          $sitename    The site name sending the mail.
	 *     @type string          $siteurl     The site URL sending the mail.
	 * }
	 */
	$content = apply_filters( 'user_request_action_email_content', $email_text, $email_data );

	$content = str_replace( '###DESCRIPTION###', $email_data['description'], $content );
	$content = str_replace( '###CONFIRM_URL###', esc_url_raw( $email_data['confirm_url'] ), $content );
	$content = str_replace( '###EMAIL###', $email_data['email'], $content );
	$content = str_replace( '###SITENAME###', $email_data['sitename'], $content );
	$content = str_replace( '###SITEURL###', esc_url_raw( $email_data['siteurl'] ), $content );

	/* translators: Privacy data request subject. 1: Site name, 2: Name of the action */
	$subject = sprintf( __( '[%1$s] Confirm Action: %2$s' ), $email_data['sitename'], $email_data['description'] );

	/**
	 * Filters the subject of the email sent when an account action is attempted.
	 *
	 * @since 4.9.6
	 *
	 * @param string $subject    The email subject.
	 * @param string $sitename   The name of the site.
	 * @param array  $email_data {
	 *     Data relating to the account action email.
	 *
	 *     @type WP_User_Request $request     User request object.
	 *     @type string          $email       The email address this is being sent to.
	 *     @type string          $description Description of the action being performed so the user knows what the email is for.
	 *     @type string          $confirm_url The link to click on to confirm the account action.
	 *     @type string          $sitename    The site name sending the mail.
	 *     @type string          $siteurl     The site URL sending the mail.
	 * }
	 */
	$subject = apply_filters( 'user_request_action_email_subject', $subject, $email_data['sitename'], $email_data );

	return wp_mail( $email_data['email'], $subject, $content );
}

/**
 * Returns a confirmation key for a user action and stores the hashed version for future comparison.
 *
 * @since 4.9.6
 *
 * @param int $request_id Request ID.
 * @return string Confirmation key.
 */
function wp_generate_user_request_key( $request_id ) {
	global $wp_hasher;

	// Generate something random for a confirmation key.
	$key = wp_generate_password( 20, false );

	// Return the key, hashed.
	if ( empty( $wp_hasher ) ) {
		require_once ABSPATH . WPINC . '/class-phpass.php';
		$wp_hasher = new PasswordHash( 8, true );
	}

	wp_update_post( array(
		'ID'                => $request_id,
		'post_status'       => 'request-pending',
		'post_password'     => $wp_hasher->HashPassword( $key ),
		'post_modified'     => current_time( 'mysql', false ),
		'post_modified_gmt' => current_time( 'mysql', true ),
	) );

	return $key;
}

/**
 * Validate a user request by comparing the key with the request's key.
 *
 * @since 4.9.6
 *
 * @param string $request_id ID of the request being confirmed.
 * @param string $key        Provided key to validate.
 * @return bool|WP_Error WP_Error on failure, true on success.
 */
function wp_validate_user_request_key( $request_id, $key ) {
	global $wp_hasher;

	$request_id = absint( $request_id );
	$request    = wp_get_user_request_data( $request_id );

	if ( ! $request ) {
		return new WP_Error( 'user_request_error', __( 'Invalid request.' ) );
	}

	if ( ! in_array( $request->status, array( 'request-pending', 'request-failed' ), true ) ) {
		return __( 'This link has expired.' );
	}

	if ( empty( $key ) ) {
		return new WP_Error( 'invalid_key', __( 'Invalid key' ) );
	}

	if ( empty( $wp_hasher ) ) {
		require_once ABSPATH . WPINC . '/class-phpass.php';
		$wp_hasher = new PasswordHash( 8, true );
	}

	$key_request_time = $request->modified_timestamp;
	$saved_key        = $request->confirm_key;

	if ( ! $saved_key ) {
		return new WP_Error( 'invalid_key', __( 'Invalid key' ) );
	}

	if ( ! $key_request_time ) {
		return new WP_Error( 'invalid_key', __( 'Invalid action' ) );
	}

	/**
	 * Filters the expiration time of confirm keys.
	 *
	 * @since 4.9.6
	 *
	 * @param int $expiration The expiration time in seconds.
	 */
	$expiration_duration = (int) apply_filters( 'user_request_key_expiration', DAY_IN_SECONDS );
	$expiration_time     = $key_request_time + $expiration_duration;

	if ( ! $wp_hasher->CheckPassword( $key, $saved_key ) ) {
		return new WP_Error( 'invalid_key', __( 'Invalid key' ) );
	}

	if ( ! $expiration_time || time() > $expiration_time ) {
		return new WP_Error( 'expired_key', __( 'The confirmation email has expired.' ) );
	}

	return true;
}

/**
 * Return data about a user request.
 *
 * @since 4.9.6
 *
 * @param int $request_id Request ID to get data about.
 * @return WP_User_Request|false
 */
function wp_get_user_request_data( $request_id ) {
	$request_id = absint( $request_id );
	$post       = get_post( $request_id );

	if ( ! $post || 'user_request' !== $post->post_type ) {
		return false;
	}

	return new WP_User_Request( $post );
}

/**
 * WP_User_Request class.
 *
 * Represents user request data loaded from a WP_Post object.
 *
 * @since 4.9.6
 */
final class WP_User_Request {
	/**
	 * Request ID.
	 *
	 * @var int
	 */
	public $ID = 0;

	/**
	 * User ID.
	 *
	 * @var int
	 */

	public $user_id = 0;

	/**
	 * User email.
	 *
	 * @var int
	 */
	public $email = '';

	/**
	 * Action name.
	 *
	 * @var string
	 */
	public $action_name = '';

	/**
	 * Current status.
	 *
	 * @var string
	 */
	public $status = '';

	/**
	 * Timestamp this request was created.
	 *
	 * @var int|null
	 */
	public $created_timestamp = null;

	/**
	 * Timestamp this request was last modified.
	 *
	 * @var int|null
	 */
	public $modified_timestamp = null;

	/**
	 * Timestamp this request was confirmed.
	 *
	 * @var int
	 */
	public $confirmed_timestamp = null;

	/**
	 * Timestamp this request was completed.
	 *
	 * @var int
	 */
	public $completed_timestamp = null;

	/**
	 * Misc data assigned to this request.
	 *
	 * @var array
	 */
	public $request_data = array();

	/**
	 * Key used to confirm this request.
	 *
	 * @var string
	 */
	public $confirm_key = '';

	/**
	 * Constructor.
	 *
	 * @since 4.9.6
	 *
	 * @param WP_Post|object $post Post object.
	 */
	public function __construct( $post ) {
		$this->ID                  = $post->ID;
		$this->user_id             = $post->post_author;
		$this->email               = $post->post_title;
		$this->action_name         = $post->post_name;
		$this->status              = $post->post_status;
		$this->created_timestamp   = strtotime( $post->post_date_gmt );
		$this->modified_timestamp  = strtotime( $post->post_modified_gmt );
		$this->confirmed_timestamp = (int) get_post_meta( $post->ID, '_wp_user_request_confirmed_timestamp', true );
		$this->completed_timestamp = (int) get_post_meta( $post->ID, '_wp_user_request_completed_timestamp', true );
		$this->request_data        = json_decode( $post->post_content, true );
		$this->confirm_key         = $post->post_password;
	}
}