<?php // phpcs:ignore WordPress.Files.FileName.InvalidClassFileName)
/**
 * Module Name: Newsletter
 * Module Description: Grow your subscriber list and deliver your content directly to their email inbox.
 * Sort Order: 9
 * Recommendation Order: 8
 * First Introduced: 1.2
 * Requires Connection: Yes
 * Requires User Connection: Yes
 * Auto Activate: No
 * Module Tags: Social
 * Feature: Engagement
 * Additional Search Queries: subscriptions, subscription, email, follow, followers, subscribers, signup, newsletter, creator
 */

// phpcs:disable Universal.Files.SeparateFunctionsFromOO.Mixed -- TODO: Move classes to appropriately-named class files.

use Automattic\Jetpack\Admin_UI\Admin_Menu;
use Automattic\Jetpack\Connection\Manager as Connection_Manager;
use Automattic\Jetpack\Connection\XMLRPC_Async_Call;
use Automattic\Jetpack\Newsletter\Settings as Newsletter_Settings;
use Automattic\Jetpack\Redirect;
use Automattic\Jetpack\Status;
use Automattic\Jetpack\Status\Host;
use Automattic\Jetpack\Subscribers_Dashboard\Dashboard as Subscribers_Dashboard;

if ( ! defined( 'ABSPATH' ) ) {
	exit( 0 );
}

add_action( 'jetpack_modules_loaded', 'jetpack_subscriptions_load' );

// Loads the User Content Link Redirection feature.
require_once __DIR__ . '/subscriptions/jetpack-user-content-link-redirection.php';

/**
 * Loads the Subscriptions module.
 */
function jetpack_subscriptions_load() {
	Jetpack::enable_module_configurable( __FILE__ );
}

/**
 * Cherry picks keys from `$_SERVER` array.
 *
 * @since 6.0.0
 *
 * @return array An array of server data.
 */
function jetpack_subscriptions_cherry_pick_server_data() {
	$data = array();

	foreach ( $_SERVER as $key => $value ) {
		if ( ! is_string( $value ) || str_starts_with( $key, 'HTTP_COOKIE' ) ) {
			continue;
		}

		if ( str_starts_with( $key, 'HTTP_' ) || in_array( $key, array( 'REMOTE_ADDR', 'REQUEST_URI', 'DOCUMENT_URI' ), true ) ) {
			$data[ $key ] = $value;
		}
	}

	return $data;
}

/**
 * Main class file for the Subscriptions module.
 *
 * @phan-constructor-used-for-side-effects
 */
class Jetpack_Subscriptions {
	/**
	 * Whether Jetpack has been instantiated or not.
	 *
	 * @var bool
	 */
	public $jetpack = false;

	/**
	 * Hash of the siteurl option.
	 *
	 * @var string
	 */
	public static $hash;

	/**
	 * Singleton
	 *
	 * @static
	 */
	public static function init() {
		static $instance = false;

		if ( ! $instance ) {
			$instance = new Jetpack_Subscriptions();
		}

		return $instance;
	}

	/**
	 * Jetpack_Subscriptions constructor.
	 */
	public function __construct() {
		$this->jetpack = Jetpack::init();

		// Don't use COOKIEHASH as it could be shared across installs && is non-unique in multisite.
		// @see: https://twitter.com/nacin/status/378246957451333632 .
		self::$hash = md5( get_option( 'siteurl' ) );

		add_filter( 'jetpack_xmlrpc_methods', array( $this, 'xmlrpc_methods' ) );

		// @todo remove sync from subscriptions and move elsewhere...

		// Add Configuration Page.
		add_action( 'admin_init', array( $this, 'configure' ) );

		// Catch subscription widget submits.
		if ( isset( $_REQUEST['jetpack_subscriptions_widget'] ) ) { // phpcs:ignore WordPress.Security.NonceVerification.Recommended -- Nonce checked in widget_submit() for logged in users.
			add_action( 'template_redirect', array( $this, 'widget_submit' ) );
		}

		// Set up the comment subscription checkboxes.
		add_filter( 'comment_form_submit_field', array( $this, 'comment_subscribe_init' ), 10, 2 );

		// Catch comment posts and check for subscriptions.
		add_action( 'comment_post', array( $this, 'comment_subscribe_submit' ), 50, 2 );

		// Adds post meta checkbox in the post submit metabox.
		add_action( 'post_submitbox_misc_actions', array( $this, 'subscription_post_page_metabox' ) );

		add_action( 'transition_post_status', array( $this, 'maybe_send_subscription_email' ), 10, 3 );

		add_filter( 'jetpack_published_post_flags', array( $this, 'set_post_flags' ), 10, 2 );

		add_filter( 'post_updated_messages', array( $this, 'update_published_message' ), 18, 1 );

		// Set "social_notifications_subscribe" option during the first-time activation.
		add_action( 'jetpack_activate_module_subscriptions', array( $this, 'set_social_notifications_subscribe' ) );
		add_action( 'jetpack_activate_module_subscriptions', array( $this, 'set_featured_image_in_email_default' ) );

		// Hide subscription messaging in Publish panel for posts that were published in the past
		add_action( 'init', array( $this, 'register_post_meta' ), 20 );
		add_action( 'transition_post_status', array( $this, 'maybe_set_first_published_status' ), 10, 3 );

		// Add Subscribers menu to Jetpack navigation.
		add_action( 'jetpack_admin_menu', array( $this, 'add_subscribers_menu' ) );

		// Customize the configuration URL to lead to the Subscriptions settings.
		add_filter(
			'jetpack_module_configuration_url_subscriptions',
			function () {
				return Jetpack::admin_url( array( 'page' => 'jetpack#/newsletter' ) );
			}
		);

		// Track categories created through the category editor page
		add_action( 'wp_ajax_add-tag', array( $this, 'track_newsletter_category_creation' ), 1 );
		$subscribers_dashboard = new Subscribers_Dashboard();
		$subscribers_dashboard::init();

		$newsletter_settings = new Newsletter_Settings();
		$newsletter_settings::init();
	}

	/**
	 * Jetpack_Subscriptions::xmlrpc_methods()
	 *
	 * Register subscriptions methods with the Jetpack XML-RPC server.
	 *
	 * @param array $methods Methods being registered.
	 */
	public function xmlrpc_methods( $methods ) {
		return array_merge(
			$methods,
			array(
				'jetpack.subscriptions.subscribe' => array( $this, 'subscribe' ),
			)
		);
	}

	/**
	 * Disable Subscribe on Single Post
	 * Register post meta
	 */
	public function subscription_post_page_metabox() {
		if (
			/**
			 * Filter whether or not to show the per-post subscription option.
			 *
			 * @module subscriptions
			 *
			 * @since 3.7.0
			 *
			 * @param bool true = show checkbox option on all new posts | false = hide the option.
			 */
			! apply_filters( 'jetpack_allow_per_post_subscriptions', false ) ) {
			return;
		}

		if ( has_filter( 'jetpack_subscriptions_exclude_these_categories' ) || has_filter( 'jetpack_subscriptions_include_only_these_categories' ) ) {
			return;
		}

		global $post;
		$disable_subscribe_value = get_post_meta( $post->ID, '_jetpack_dont_email_post_to_subs', true );
		// only show checkbox if post hasn't been published and is a 'post' post type.
		if ( get_post_status( $post->ID ) !== 'publish' && get_post_type( $post->ID ) === 'post' ) :
			// Nonce it.
			wp_nonce_field( 'disable_subscribe', 'disable_subscribe_nonce' );
			?>
			<div class="misc-pub-section">
				<label for="_jetpack_dont_email_post_to_subs"><?php esc_html_e( 'Jetpack Subscriptions:', 'jetpack' ); ?></label><br>
				<input type="checkbox" name="_jetpack_dont_email_post_to_subs" id="jetpack-per-post-subscribe" value="1" <?php checked( $disable_subscribe_value, 1, true ); ?> />
				<?php esc_html_e( 'Don&#8217;t send this to subscribers', 'jetpack' ); ?>
			</div>
			<?php
		endif;
	}

	/**
	 * Checks whether or not the post should be emailed to subscribers
	 *
	 * It checks for the following things in order:
	 * - Usage of filter jetpack_subscriptions_exclude_these_categories
	 * - Usage of filter jetpack_subscriptions_include_only_these_categories
	 * - Existence of the per-post checkbox option
	 *
	 * Only one of these can be used at any given time.
	 *
	 * @param string $new_status Tthe "new" post status of the transition when saved.
	 * @param string $old_status The "old" post status of the transition when saved.
	 * @param object $post obj The post object.
	 */
	public function maybe_send_subscription_email( $new_status, $old_status, $post ) {

		if ( defined( 'DOING_AUTOSAVE' ) && DOING_AUTOSAVE ) {
			return;
		}

		// Make sure that the checkbox is preseved.
		if ( ! empty( $_POST['disable_subscribe_nonce'] ) && wp_verify_nonce( $_POST['disable_subscribe_nonce'], 'disable_subscribe' ) ) { // phpcs:ignore WordPress.Security.ValidatedSanitizedInput -- WP Core doesn't unslash or sanitize nonces either.
			$set_checkbox = isset( $_POST['_jetpack_dont_email_post_to_subs'] ) ? 1 : 0;
			update_post_meta( $post->ID, '_jetpack_dont_email_post_to_subs', $set_checkbox );
		}
	}

	/**
	 * Message used when publishing a post.
	 *
	 * @param array $messages Message array for a post.
	 */
	public function update_published_message( $messages ) {
		global $post;
		if ( ! $this->should_email_post_to_subscribers( $post ) ) {
			return $messages;
		}

		$view_post_link_html = sprintf(
			' <a href="%1$s">%2$s</a>',
			esc_url( get_permalink( $post ) ),
			__( 'View post', 'jetpack' )
		);

		$messages['post'][6] = sprintf(
			/* translators: Message shown after a post is published */
			esc_html__( 'Post published and sending emails to subscribers.', 'jetpack' )
		) . $view_post_link_html;
		return $messages;
	}

	/**
	 * Determine if a post should notifiy subscribers via email.
	 *
	 * @param object $post The post.
	 */
	public function should_email_post_to_subscribers( $post ) {
		$should_email = true;
		if ( get_post_meta( $post->ID, '_jetpack_dont_email_post_to_subs', true ) ) {
			return false;
		}

		// Only posts are currently supported.
		if ( 'post' !== $post->post_type ) {
			return false;
		}

		// Private posts are not sent to subscribers.
		if ( 'private' === $post->post_status ) {
			return false;
		}

		/**
		 * Array of categories that will never trigger subscription emails.
		 *
		 * Will not send subscription emails from any post from within these categories.
		 *
		 * @module subscriptions
		 *
		 * @since 3.7.0
		 *
		 * @param array $args Array of category slugs or ID's.
		 */
		$excluded_categories = apply_filters( 'jetpack_subscriptions_exclude_these_categories', array() );

		// Never email posts from these categories.
		if ( ! empty( $excluded_categories ) && in_category( $excluded_categories, $post->ID ) ) {
			$should_email = false;
		}

		/**
		 * ONLY send subscription emails for these categories
		 *
		 * Will ONLY send subscription emails to these categories.
		 *
		 * @module subscriptions
		 *
		 * @since 3.7.0
		 *
		 * @param array $args Array of category slugs or ID's.
		 */
		$only_these_categories = apply_filters( 'jetpack_subscriptions_exclude_all_categories_except', array() );

		// Only emails posts from these categories.
		if ( ! empty( $only_these_categories ) && ! in_category( $only_these_categories, $post->ID ) ) {
			$should_email = false;
		}

		return $should_email;
	}

	/**
	 * Retrieve which flags should be added to a particular post.
	 *
	 * @param array  $flags Flags to be added.
	 * @param object $post A post object.
	 */
	public function set_post_flags( $flags, $post ) {
		$flags['send_subscription'] = $this->should_email_post_to_subscribers( $post );
		return $flags;
	}

	/**
	 * Jetpack_Subscriptions::configure()
	 *
	 * Jetpack Subscriptions configuration screen.
	 */
	public function configure() {
		// Create the section.
		add_settings_section(
			'jetpack_subscriptions',
			__( 'Jetpack Subscriptions Settings', 'jetpack' ),
			array( $this, 'subscriptions_settings_section' ),
			'discussion'
		);

		/** Subscribe to Posts */

		add_settings_field(
			'jetpack_subscriptions_post_subscribe',
			__( 'Follow Blog', 'jetpack' ),
			array( $this, 'subscription_post_subscribe_setting' ),
			'discussion',
			'jetpack_subscriptions'
		);

		register_setting(
			'discussion',
			'stb_enabled'
		);

		/** Subscribe to Comments */

		add_settings_field(
			'jetpack_subscriptions_comment_subscribe',
			__( 'Follow Comments', 'jetpack' ),
			array( $this, 'subscription_comment_subscribe_setting' ),
			'discussion',
			'jetpack_subscriptions'
		);

		register_setting(
			'discussion',
			'stc_enabled'
		);

		/** Email me whenever: Someone subscribes to my blog */
		/* @since 8.1 */

		add_settings_section(
			'notifications_section',
			__( 'Someone subscribes to my blog', 'jetpack' ),
			array( $this, 'social_notifications_subscribe_section' ),
			'discussion'
		);

		add_settings_field(
			'jetpack_subscriptions_social_notifications_subscribe',
			__( 'Email me whenever', 'jetpack' ),
			array( $this, 'social_notifications_subscribe_field' ),
			'discussion',
			'notifications_section'
		);

		register_setting(
			'discussion',
			'social_notifications_subscribe',
			array( $this, 'social_notifications_subscribe_validate' )
		);
	}

	/**
	 * Discussions setting section blurb.
	 */
	public function subscriptions_settings_section() {
		?>
		<p id="jetpack-subscriptions-settings"><?php esc_html_e( 'Change whether your visitors can subscribe to your posts or comments or both.', 'jetpack' ); ?></p>

		<?php
	}

	/**
	 * Post Subscriptions Toggle.
	 */
	public function subscription_post_subscribe_setting() {

		$stb_enabled = get_option( 'stb_enabled', 1 );
		?>

		<p class="description">
			<input type="checkbox" name="stb_enabled" id="jetpack-post-subscribe" value="1" <?php checked( $stb_enabled, 1 ); ?> />
			<?php
			echo wp_kses(
				__(
					"Show a <em>'follow blog'</em> option in the comment form",
					'jetpack'
				),
				array( 'em' => array() )
			);
			?>
		</p>
		<?php
	}

	/**
	 * Comments Subscriptions Toggle.
	 */
	public function subscription_comment_subscribe_setting() {

		$stc_enabled = get_option( 'stc_enabled', 1 );
		?>

		<p class="description">
			<input type="checkbox" name="stc_enabled" id="jetpack-comment-subscribe" value="1" <?php checked( $stc_enabled, 1 ); ?> />
			<?php
			echo wp_kses(
				__(
					"Show a <em>'follow comments'</em> option in the comment form",
					'jetpack'
				),
				array( 'em' => array() )
			);
			?>
		</p>

		<?php
	}

	/**
	 * Someone subscribes to my blog section
	 *
	 * @since 8.1
	 */
	public function social_notifications_subscribe_section() {
		// Atypical usage here. We emit jquery to move subscribe notification checkbox to be with the rest of the email notification settings.
		?>
		<script type="text/javascript">
			jQuery( function( $ )  {
				var table = $( '#social_notifications_subscribe' ).parents( 'table:first' ),
					header = table.prevAll( 'h2:first' ),
					newParent = $( '#moderation_notify' ).parent( 'label' ).parent();

				if ( ! table.length || ! header.length || ! newParent.length ) {
					return;
				}

				newParent.append( '<br/>' ).append( table.end().parent( 'label' ).siblings().andSelf() );
				header.remove();
				table.remove();
			} );
		</script>
		<?php
	}

	/**
	 * Someone subscribes to my blog Toggle
	 *
	 * @since 8.1
	 */
	public function social_notifications_subscribe_field() {
		$checked = (int) ( 'on' === get_option( 'social_notifications_subscribe', 'on' ) );
		?>

		<label>
			<input type="checkbox" name="social_notifications_subscribe" id="social_notifications_subscribe" value="1" <?php checked( $checked ); ?> />
			<?php
				/* translators: this is a label for a setting that starts with "Email me whenever" */
				esc_html_e( 'Someone subscribes to my blog', 'jetpack' );
			?>
		</label>
		<?php
	}

	/**
	 * Validate "Someone subscribes to my blog" option
	 *
	 * @since 8.1
	 *
	 * @param String $input the input string to be validated.
	 * @return string on|off
	 */
	public function social_notifications_subscribe_validate( $input ) {
		// If it's not set (was unchecked during form submission) or was set to off (during option update), return 'off'.
		if ( ! $input || 'off' === $input ) {
			return 'off';
		}

		// Otherwise we return 'on'.
		return 'on';
	}

	/**
	 * Jetpack_Subscriptions::subscribe()
	 *
	 * Send a synchronous XML-RPC subscribe to blog posts or subscribe to post comments request.
	 *
	 * @param string $email being subscribed.
	 * @param array  $post_ids (optional) defaults to 0 for blog posts only: array of post IDs to subscribe to blog's posts.
	 * @param bool   $async    (optional) Should the subscription be performed asynchronously?  Defaults to true.
	 * @param array  $extra_data Additional data passed to the `jetpack.subscribeToSite` call.
	 *
	 * @return true|WP_Error true on success
	 *  invalid_email   : not a valid email address
	 *  invalid_post_id : not a valid post ID
	 *  unknown_post_id : unknown post
	 *  not_subscribed  : strange error.  Jetpack servers at WordPress.com could subscribe the email.
	 *  disabled        : Site owner has disabled subscriptions.
	 *  active          : Already subscribed.
	 *  pending         : Tried to subscribe before but the confirmation link is never clicked. No confirmation email is sent.
	 *  unknown         : strange error.  Jetpack servers at WordPress.com returned something malformed.
	 *  unknown_status  : strange error.  Jetpack servers at WordPress.com returned something I didn't understand.
	 */
	public function subscribe( $email, $post_ids = 0, $async = true, $extra_data = array() ) {
		if ( ! is_email( $email ) ) {
			return new WP_Error( 'invalid_email' );
		}

		if ( ! $async ) {
			$xml = new Jetpack_IXR_ClientMulticall();
		}

		foreach ( (array) $post_ids as $post_id ) {
			$post_id = (int) $post_id;
			if ( $post_id < 0 ) {
				return new WP_Error( 'invalid_post_id' );
			} elseif ( $post_id && ! get_post( $post_id ) ) {
				return new WP_Error( 'unknown_post_id' );
			}

			if ( $async ) {
				XMLRPC_Async_Call::add_call( 'jetpack.subscribeToSite', 0, $email, $post_id, serialize( $extra_data ) ); //phpcs:ignore WordPress.PHP.DiscouragedPHPFunctions.serialize_serialize
			} else {
				// @phan-suppress-next-line PhanPossiblyUndeclaredVariable -- $xml is set when $async is false
				$xml->addCall( 'jetpack.subscribeToSite', $email, $post_id, serialize( $extra_data ) ); //phpcs:ignore WordPress.PHP.DiscouragedPHPFunctions.serialize_serialize
			}
		}

		if ( $async ) {
			return;
		}

		// Call.
		// @phan-suppress-next-line PhanPossiblyUndeclaredVariable -- $xml is set when $async is false, otherwise we return early
		$xml->query();

		// @phan-suppress-next-line PhanPossiblyUndeclaredVariable -- $xml is set when $async is false, otherwise we return early
		if ( $xml->isError() ) {
			// @phan-suppress-next-line PhanPossiblyUndeclaredVariable -- $xml is set when $async is false, otherwise we return early
			return $xml->get_jetpack_error();
		}

		// @phan-suppress-next-line PhanPossiblyUndeclaredVariable -- $xml is set when $async is false
		$responses = $xml->getResponse();

		$r = array();
		foreach ( (array) $responses as $response ) {
			if ( isset( $response['faultCode'] ) || isset( $response['faultString'] ) ) {
				// @phan-suppress-next-line PhanPossiblyUndeclaredVariable -- $xml is set when $async is false
				$r[] = $xml->get_jetpack_error( $response['faultCode'], $response['faultString'] );
				continue;
			}

			if ( ! is_array( $response[0] ) || empty( $response[0]['status'] ) ) {
				$r[] = new WP_Error( 'unknown' );
				continue;
			}

			switch ( $response[0]['status'] ) {
				case 'error':
					$r[] = new WP_Error( 'not_subscribed' );
					continue 2;
				case 'disabled':
					$r[] = new WP_Error( 'disabled' );
					continue 2;
				case 'active':
					$r[] = new WP_Error( 'active' );
					continue 2;
				case 'confirming':
					$r[] = true;
					continue 2;
				case 'pending':
					$r[] = new WP_Error( 'pending' );
					continue 2;
				default:
					$r[] = new WP_Error( 'unknown_status', (string) $response[0]['status'] );
					continue 2;
			}
		}

		return $r;
	}

	/**
	 * Jetpack_Subscriptions::widget_submit()
	 *
	 * When a user submits their email via the blog subscription widget, check the details and call the subsribe() method.
	 */
	public function widget_submit() {
		// Check the nonce.
		if ( ! wp_verify_nonce( isset( $_REQUEST['_wpnonce'] ) ? sanitize_key( $_REQUEST['_wpnonce'] ) : '', 'blogsub_subscribe_' . \Jetpack_Options::get_option( 'id' ) ) ) {
			return false;
		}

		if ( empty( $_REQUEST['email'] ) || ! is_string( $_REQUEST['email'] ) ) {
			return false;
		}

		$redirect_fragment = false;
		if ( isset( $_REQUEST['redirect_fragment'] ) ) {
			$redirect_fragment = preg_replace( '/[^a-z0-9_-]/i', '', $_REQUEST['redirect_fragment'] ); // phpcs:ignore WordPress.Security.ValidatedSanitizedInput -- This is manually unslashing and sanitizing.
		}
		if ( ! $redirect_fragment || ! is_string( $redirect_fragment ) ) {
			$redirect_fragment = 'subscribe-blog';
		}

		$subscribe = self::subscribe(
			isset( $_REQUEST['email'] ) ? wp_unslash( $_REQUEST['email'] ) : null, // phpcs:ignore WordPress.Security.ValidatedSanitizedInput.InputNotSanitized -- Validated inside self::subscribe().
			0,
			false,
			array(
				'source'         => 'widget',
				'widget-in-use'  => is_active_widget( false, false, 'blog_subscription', true ) ? 'yes' : 'no',
				'comment_status' => '',
				'server_data'    => jetpack_subscriptions_cherry_pick_server_data(),
			)
		);

		if ( is_wp_error( $subscribe ) ) {
			$error = $subscribe->get_error_code();
		} else {
			$error = false;
			foreach ( $subscribe as $response ) {
				if ( is_wp_error( $response ) ) {
					$error = $response->get_error_code();
					break;
				}
			}
		}

		switch ( $error ) {
			case false:
				$result = 'success';
				break;
			case 'invalid_email':
				$result = $error;
				break;
			case 'blocked_email':
				$result = 'opted_out';
				break;
			case 'active':
				$result = 'already';
				break;
			case 'flooded_email':
				$result = 'many_pending_subs';
				break;
			case 'pending':
				$result = 'pending';
				break;
			default:
				$result = 'error';
				break;
		}

		$redirect = add_query_arg( 'subscribe', $result );

		/**
		 * Fires on each subscription form submission.
		 *
		 * @module subscriptions
		 *
		 * @since 3.7.0
		 *
		 * @param string $result Result of form submission: success, invalid_email, already, error.
		 */
		do_action( 'jetpack_subscriptions_form_submission', $result );

		wp_safe_redirect( "$redirect#$redirect_fragment" );
		exit( 0 );
	}

	/**
	 * Jetpack_Subscriptions::comment_subscribe_init()
	 *
	 * Set up and add the comment subscription checkbox to the comment form.
	 *
	 * @param string $submit_button HTML markup for the submit field.
	 */
	public function comment_subscribe_init( $submit_button ) {
		global $post;

		// Subscriptions are only available for posts so far.
		if ( ! $post || 'post' !== $post->post_type ) {
			return $submit_button;
		}

		$comments_checked = '';
		$blog_checked     = '';

		// Check for a comment / blog submission and set a cookie to retain the setting and check the boxes.
		if ( isset( $_COOKIE[ 'jetpack_comments_subscribe_' . self::$hash . '_' . $post->ID ] ) ) {
			$comments_checked = ' checked="checked"';
		}

		if ( isset( $_COOKIE[ 'jetpack_blog_subscribe_' . self::$hash ] ) ) {
			$blog_checked = ' checked="checked"';
		}

		// Some themes call this function, don't show the checkbox again.
		remove_action( 'comment_form', 'subscription_comment_form' );

		// Check if Mark Jaquith's Subscribe to Comments plugin is active - if so, suppress Jetpack checkbox.

		$str = '';

		if ( false === has_filter( 'comment_form', 'show_subscription_checkbox' ) && 1 === (int) get_option( 'stc_enabled', 1 ) && empty( $post->post_password ) && 'post' === get_post_type() ) {
			// Subscribe to comments checkbox.
			$str             .= '<p class="comment-subscription-form"><input type="checkbox" name="subscribe_comments" id="subscribe_comments" value="subscribe" style="width: auto; -moz-appearance: checkbox; -webkit-appearance: checkbox;"' . $comments_checked . ' /> ';
			$comment_sub_text = __( 'Notify me of follow-up comments by email.', 'jetpack' );
			$str             .= '<label class="subscribe-label" id="subscribe-label" for="subscribe_comments">' . esc_html(
				/**
				 * Filter the Subscribe to comments text appearing below the comment form.
				 *
				 * @module subscriptions
				 *
				 * @since 3.4.0
				 *
				 * @param string $comment_sub_text Subscribe to comments text.
				 */
				apply_filters( 'jetpack_subscribe_comment_label', $comment_sub_text )
			) . '</label>';
			$str .= '</p>';
		}

		if ( 1 === (int) get_option( 'stb_enabled', 1 ) ) {
			// Subscribe to blog checkbox.
			$str          .= '<p class="comment-subscription-form"><input type="checkbox" name="subscribe_blog" id="subscribe_blog" value="subscribe" style="width: auto; -moz-appearance: checkbox; -webkit-appearance: checkbox;"' . $blog_checked . ' /> ';
			$blog_sub_text = __( 'Notify me of new posts by email.', 'jetpack' );
			$str          .= '<label class="subscribe-label" id="subscribe-blog-label" for="subscribe_blog">' . esc_html(
				/**
				 * Filter the Subscribe to blog text appearing below the comment form.
				 *
				 * @module subscriptions
				 *
				 * @since 3.4.0
				 *
				 * @param string $comment_sub_text Subscribe to blog text.
				 */
				apply_filters( 'jetpack_subscribe_blog_label', $blog_sub_text )
			) . '</label>';
			$str .= '</p>';
		}

		/**
		 * Filter the output of the subscription options appearing below the comment form.
		 *
		 * @module subscriptions
		 *
		 * @since 1.2.0
		 *
		 * @param string $str Comment Subscription form HTML output.
		 */
		$str = apply_filters( 'jetpack_comment_subscription_form', $str );

		return $str . $submit_button;
	}

	/**
	 * Jetpack_Subscriptions::comment_subscribe_init()
	 *
	 * When a user checks the comment subscribe box and submits a comment, subscribe them to the comment thread.
	 *
	 * @param int|string $comment_id Comment thread being subscribed to.
	 * @param string     $approved Comment status.
	 */
	public function comment_subscribe_submit( $comment_id, $approved ) {
		if ( 'spam' === $approved ) {
			return;
		}

		$comment = get_comment( $comment_id );
		if ( ! $comment ) {
			return;
		}

		// Set cookies for this post/comment.
		$this->set_cookies( isset( $_REQUEST['subscribe_comments'] ), $comment->comment_post_ID, isset( $_REQUEST['subscribe_blog'] ) ); // phpcs:ignore WordPress.Security.NonceVerification.Recommended

		if ( ! isset( $_REQUEST['subscribe_comments'] ) && ! isset( $_REQUEST['subscribe_blog'] ) ) {  // phpcs:ignore WordPress.Security.NonceVerification.Recommended
			return;
		}

		$post_ids = array();

		if ( isset( $_REQUEST['subscribe_comments'] ) ) { // phpcs:ignore WordPress.Security.NonceVerification.Recommended
			$post_ids[] = $comment->comment_post_ID;
		}

		if ( isset( $_REQUEST['subscribe_blog'] ) ) { // phpcs:ignore WordPress.Security.NonceVerification.Recommended
			$post_ids[] = 0;
		}

		$result = self::subscribe(
			$comment->comment_author_email,
			$post_ids,
			true,
			array(
				'source'         => 'comment-form',
				'widget-in-use'  => is_active_widget( false, false, 'blog_subscription', true ) ? 'yes' : 'no',
				'comment_status' => $approved,
				'server_data'    => jetpack_subscriptions_cherry_pick_server_data(),
			)
		);

		/**
		 * Fires on each comment subscription form submission.
		 *
		 * @module subscriptions
		 *
		 * @since 5.5.0
		 *
		 * @param NULL|WP_Error $result Result of form submission: NULL on success, WP_Error otherwise.
		 * @param array $post_ids An array of post IDs that the user subscribed to, 0 means blog subscription.
		 */
		do_action( 'jetpack_subscriptions_comment_form_submission', $result, $post_ids );
	}

	/**
	 * Jetpack_Subscriptions::set_cookies()
	 *
	 * Set a cookie to save state on the comment and post subscription checkboxes.
	 *
	 * @param bool $subscribe_to_post Whether the user chose to subscribe to subsequent comments on this post.
	 * @param int  $post_id If $subscribe_to_post is true, the post ID they've subscribed to.
	 * @param bool $subscribe_to_blog Whether the user chose to subscribe to all new posts on the blog.
	 */
	public function set_cookies( $subscribe_to_post = false, $post_id = null, $subscribe_to_blog = false ) {
		$post_id = (int) $post_id;

		/** This filter is already documented in core/wp-includes/comment-functions.php */
		$cookie_lifetime = apply_filters( 'comment_cookie_lifetime', YEAR_IN_SECONDS );

		/**
		 * Filter the Jetpack Comment cookie path.
		 *
		 * @module subscriptions
		 *
		 * @since 2.5.0
		 *
		 * @param string COOKIEPATH Cookie path.
		 */
		$cookie_path = apply_filters( 'jetpack_comment_cookie_path', COOKIEPATH );

		/**
		 * Filter the Jetpack Comment cookie domain.
		 *
		 * @module subscriptions
		 *
		 * @since 2.5.0
		 *
		 * @param string COOKIE_DOMAIN Cookie domain.
		 */
		$cookie_domain = apply_filters( 'jetpack_comment_cookie_domain', COOKIE_DOMAIN );

		if ( $subscribe_to_post && $post_id >= 0 ) {
			setcookie( 'jetpack_comments_subscribe_' . self::$hash . '_' . $post_id, '1', time() + $cookie_lifetime, $cookie_path, $cookie_domain, is_ssl(), true );
		} else {
			setcookie( 'jetpack_comments_subscribe_' . self::$hash . '_' . $post_id, '', time() - 3600, $cookie_path, $cookie_domain, is_ssl(), true );
		}

		if ( $subscribe_to_blog ) {
			setcookie( 'jetpack_blog_subscribe_' . self::$hash, '1', time() + $cookie_lifetime, $cookie_path, $cookie_domain, is_ssl(), true );
		} else {
			setcookie( 'jetpack_blog_subscribe_' . self::$hash, '', time() - 3600, $cookie_path, $cookie_domain, is_ssl(), true );
		}
	}

	/**
	 * Set the social_notifications_subscribe option to `off` when the Subscriptions module is activated in the first time.
	 *
	 * @since 8.1
	 *
	 * @return void
	 */
	public function set_social_notifications_subscribe() {
		if ( false === get_option( 'social_notifications_subscribe' ) ) {
			add_option( 'social_notifications_subscribe', 'off' );
		}
	}

	/**
	 * Set the featured image in email option to `1` when the Subscriptions module is activated in the first time.
	 *
	 * @return void
	 */
	public function set_featured_image_in_email_default() {
		add_option( 'wpcom_featured_image_in_email', 1 );
	}

	/**
	 * Save a flag when a post was ever published.
	 *
	 * It saves the post meta when the post was published and becomes a draft.
	 * Then this meta is used to hide subscription messaging in Publish panel.
	 *
	 * @param string $new_status Tthe "new" post status of the transition when saved.
	 * @param string $old_status The "old" post status of the transition when saved.
	 * @param object $post obj The post object.
	 */
	public function maybe_set_first_published_status( $new_status, $old_status, $post ) {
		$was_post_ever_published = get_post_meta( $post->ID, '_jetpack_post_was_ever_published', true );
		if ( ! $was_post_ever_published && 'publish' === $old_status && 'draft' === $new_status ) {
			update_post_meta( $post->ID, '_jetpack_post_was_ever_published', true );
		}
	}

	/**
	 * Checks if the current user can publish posts.
	 *
	 * @return bool
	 */
	public function first_published_status_meta_auth_callback() {
		/**
		 * Filter the capability to view if a post was ever published in the Subscription Module.
		 *
		 * @module subscriptions
		 *
		 * @since 13.4
		 *
		 * @param string $capability User capability needed to view if a post was ever published. Default to publish_posts.
		 */
		$capability = apply_filters( 'jetpack_subscriptions_post_was_ever_published_capability', 'publish_posts' );
		if ( current_user_can( $capability ) ) {
			return true;
		}
		return false;
	}

	/**
	 * Registers the 'post_was_ever_published' post meta for use in the REST API.
	 */
	public function register_post_meta() {
		$jetpack_post_was_ever_published = array(
			'type'          => 'boolean',
			'description'   => __( 'Whether the post was ever published.', 'jetpack' ),
			'single'        => true,
			'default'       => false,
			'show_in_rest'  => array(
				'name' => 'jetpack_post_was_ever_published',
			),
			'auth_callback' => array( $this, 'first_published_status_meta_auth_callback' ),
		);

		register_meta( 'post', '_jetpack_post_was_ever_published', $jetpack_post_was_ever_published );
	}

	/**
	 * Create a Subscribers menu displayed on self-hosted sites.
	 *
	 * - It is not displayed on WordPress.com sites.
	 * - It directs you to Calypso to the existing Subscribers page.
	 *
	 * @return void
	 */
	public function add_subscribers_menu() {
		/**
		 * Enables the new in development subscribers in wp-admin dashboard.
		 *
		 * @since 9.5.0
		 *
		 * @param bool If the new dashboard is enabled. Default false.
		 */
		if ( apply_filters( 'jetpack_wp_admin_subscriber_management_enabled', false ) ) {
			return;
		}

		/*
		 * Do not display any menu on WoA and WordPress.com Simple sites (unless Classic wp-admin is enabled).
		 * They already get a menu item under Users via nav-unification.
		 */
		if ( ( new Host() )->is_wpcom_platform() && get_option( 'wpcom_admin_interface' ) !== 'wp-admin' ) {
			return;
		}

		$status = new Status();

		/*
		 * Do not display if we're in Offline mode,
		 * or if the user is not connected.
		 */
		if (
			$status->is_offline_mode()
			|| ! ( new Connection_Manager( 'jetpack' ) )->is_user_connected()
		) {
			return;
		}

		$blog_id = Connection_Manager::get_site_id( true );

		$link = Redirect::get_url(
			'jetpack-menu-jetpack-manage-subscribers',
			array( 'site' => $blog_id ? $blog_id : $status->get_site_suffix() )
		);

		Admin_Menu::add_menu(
			__( 'Subscribers', 'jetpack' ),
			__( 'Subscribers', 'jetpack' ) . ' <span class="dashicons dashicons-external"></span>',
			'manage_options',
			esc_url( $link ),
			null,
			11
		);
	}

	/**
	 * Record tracks event if categories is created when user enters
	 * the edit category page through the newsletter settings page.
	 *
	 * @return void
	 */
	public function track_newsletter_category_creation() {

		// phpcs:disable WordPress.Security.NonceVerification.Missing
		if ( empty( $_POST['_wp_http_referer'] ) ) {
			return;
		}

		if ( strpos( sanitize_url( wp_unslash( $_POST['_wp_http_referer'] ) ), 'referer=newsletter-categories' ) > -1 ) {

			$parent = filter_var( empty( $_POST['parent'] ) ? 0 : wp_unslash( $_POST['parent'] ), FILTER_SANITIZE_NUMBER_INT );

			$is_child_category = $parent > 0;

			$tracking = new Automattic\Jetpack\Tracking();
			$tracking->tracks_record_event(
				wp_get_current_user(),
				'jetpack_newsletter_add_category',
				array(
					'is_child_category' => $is_child_category,
				)
			);
		}
	}
}

Jetpack_Subscriptions::init();

require __DIR__ . '/subscriptions/views.php';
require __DIR__ . '/subscriptions/subscribe-modal/class-jetpack-subscribe-modal.php';
require __DIR__ . '/subscriptions/subscribe-overlay/class-jetpack-subscribe-overlay.php';
require __DIR__ . '/subscriptions/subscribe-floating-button/class-jetpack-subscribe-floating-button.php';
require __DIR__ . '/subscriptions/newsletter-widget/class-jetpack-newsletter-dashboard-widget.php';
