<?php // phpcs:ignore WordPress.Files.FileName.InvalidClassFileName
/**
* Automatically inserts the <!--nextpage--> Quicktag into WordPress posts, pages, or custom post type content.
*
* Plugin Name: Automatically Paginate Posts
* Plugin URI: http://www.oomphinc.com/plugins-modules/automatically-paginate-posts/
* Description: Automatically inserts the <!--nextpage--> Quicktag into WordPress posts, pages, or custom post type content.
* Version: 0.3.1
* Author: Erick Hitter & Oomph, Inc.
* Author URI: http://www.oomphinc.com/
* Text Domain: automatically-paginate-posts
* Domain Path: /languages/
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program 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 General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
*
* @package automatically-paginate-posts
*/
require_once dirname( __FILE__ ) . '/inc/class-block-editor.php';
/**
* Class Automatically_Paginate_Posts.
*/
class Automatically_Paginate_Posts {
/**
* WordPress Quicktag that creates pagination.
*/
const QUICKTAG = '<!--nextpage-->';
/**
* String length of nextpage Quicktag.
*/
const QUICKTAG_LENGTH = 15;
/**
* Supported post types.
*
* @var array
*/
private $post_types;
/**
* Default supported post types.
*
* @var array
*/
private $post_types_default = array( 'post' );
/**
* Desired number of pages to split to.
*
* @var int
*/
private $num_pages;
/**
* Method for splitting content, either words or desired number of pages.
*
* @var string
*/
private $paging_type_default = 'pages';
/**
* Default number of pages to split to.
*
* @var int
*/
private $num_pages_default = 2;
/**
* Desired number of words per pages.
*
* @var int
*/
private $num_words;
/**
* Default number of words to split on.
*
* @var string|int
*/
private $num_words_default = '';
/**
* When splitting by word counts, these blocks are considered. Tags are
* stripped and remaining content is counted.
*
* @var array
*/
private $supported_block_types_for_word_counts = array(
'core/paragraph',
);
/**
* Allowed split types.
*
* @var array
*/
private $paging_types_allowed = array( 'pages', 'words' );
/**
* Supported-post-types option name.
*
* @var string
*/
private $option_name_post_types = 'autopaging_post_types';
/**
* Split-type option name.
*
* @var string
*/
private $option_name_paging_type = 'pages';
/**
* Option holding number of pages to split to.
*
* @var string
*/
private $option_name_num_pages = 'autopaging_num_pages';
/**
* Option holding number of words to split on.
*
* @var string
*/
private $option_name_num_words = 'autopaging_num_words';
/**
* Meta key used to indicate that a post shouldn't be automatically split.
*
* @var string
*/
private $meta_key_disable_autopaging = '_disable_autopaging';
/**
* Class constructor.
*
* @return void
*/
public function __construct() {
$this->setup_hooks();
new Automatically_Paginate_Posts\Block_Editor( $this );
}
/**
* Register hooks.
*
* @return void
*/
protected function setup_hooks() {
add_action( 'plugins_loaded', array( $this, 'load_textdomain' ) );
add_action( 'init', array( $this, 'action_init' ) );
// Admin settings.
register_uninstall_hook( __FILE__, array( 'Automatically_Paginate_Posts', 'uninstall' ) );
add_filter( 'plugin_action_links', array( $this, 'filter_plugin_action_links' ), 10, 2 );
add_action( 'admin_init', array( $this, 'action_admin_init' ) );
// Post-type settings.
add_action( 'add_meta_boxes', array( $this, 'action_add_meta_boxes' ) );
add_action( 'save_post', array( $this, 'action_save_post' ) );
add_filter( 'the_posts', array( $this, 'filter_the_posts' ) );
}
/**
* Allow access to meta key for disabling autopaging.
*
* @param string $name Property name.
* @return array|string|null
*/
public function __get( $name ) {
if ( 'meta_key' === $name ) {
return $this->meta_key_disable_autopaging;
}
if ( 'post_types' === $name ) {
if ( ! did_action( 'init' ) ) {
_doing_it_wrong(
__METHOD__,
esc_html__(
'Post types can only be retrieved after the "init" hook.',
'automatically-paginate-posts'
),
'0.3'
);
return null;
}
return $this->post_types;
}
return null;
}
/**
* Prevent setting properties.
*
* @param string $name Property name.
* @param string $value Property value.
* @return false
*/
public function __set( $name, $value ) {
return false;
}
/**
* Indicate if a property is set.
*
* @param string $name Property name.
* @return bool
*/
public function __isset( $name ) {
if ( 'meta_key' === $name ) {
return true;
}
if ( 'post_types' === $name ) {
return did_action( 'init' );
}
return false;
}
/**
* Load plugin translations.
*
* @return void
*/
public function load_textdomain() {
load_plugin_textdomain(
'automatically-paginate-posts',
false,
dirname( plugin_basename( __FILE__ ) ) . '/languages/'
);
}
/**
* Set post types this plugin can act on, either from Reading page or via filter.
* Also sets default number of pages to break content over, either from Reading page or via filter.
*
* @uses apply_filters, get_option
* @action init
* @return void
*/
public function action_init() {
// Post types.
$this->post_types = apply_filters( 'autopaging_post_types', get_option( $this->option_name_post_types, $this->post_types_default ) );
// Number of pages to break over.
$this->num_pages = absint( apply_filters( 'autopaging_num_pages_default', get_option( $this->option_name_num_pages, $this->num_pages_default ) ) );
if ( 0 == $this->num_pages ) {
$this->num_pages = $this->num_pages_default;
}
// Number of words to break over.
$this->num_words = absint( apply_filters( 'autopaging_num_words_default', get_option( $this->option_name_num_words, $this->num_words_default ) ) );
if ( 0 == $this->num_words ) {
$this->num_words = $this->num_words_default;
}
// Supported blocks for splitting by words.
$this->supported_block_types_for_word_counts = apply_filters(
'autopaging_supported_block_types_for_word_counts',
$this->supported_block_types_for_word_counts
);
}
/**
* Delete plugin settings when uninstalled.
* Options names here must match those defined in Class Variables section above.
*
* @uses delete_option
* @action uninstall
* @return void
*/
public function uninstall() {
delete_option( 'autopaging_post_types' );
delete_option( 'autopaging_paging_type' );
delete_option( 'autopaging_num_pages' );
delete_option( 'autopaging_num_words' );
}
/**
* Add settings link to plugin's row actions
*
* @param array $actions Plugin's actions.
* @param string $file Plugin filename.
* @filter plugin_action_links,
*/
public function filter_plugin_action_links( $actions, $file ) {
if ( false !== strpos( $file, basename( __FILE__ ) ) ) {
$actions['settings'] = '<a href="' . admin_url( 'options-reading.php' ) . '">Settings</a>';
}
return $actions;
}
/**
* Register settings and settings sections.
* Settings appear on the Reading page.
*
* @uses register_setting, add_settings_section, __, __return_false, add_settings_field
* @action admin_init
* @return void
*/
public function action_admin_init() {
register_setting( 'reading', $this->option_name_post_types, array( $this, 'sanitize_supported_post_types' ) );
register_setting( 'reading', $this->option_name_paging_type, array( $this, 'sanitize_paging_type' ) );
register_setting( 'reading', $this->option_name_num_pages, array( $this, 'sanitize_num_pages' ) );
register_setting( 'reading', $this->option_name_num_words, array( $this, 'sanitize_num_words' ) );
add_settings_section( 'autopaging', __( 'Automatically Paginate Posts', 'automatically-paginate-posts' ), '__return_false', 'reading' );
add_settings_field( 'autopaging-post-types', __( 'Supported post types:', 'automatically-paginate-posts' ), array( $this, 'settings_field_post_types' ), 'reading', 'autopaging' );
add_settings_field( 'autopaging-paging-type', __( 'Split post by:', 'automatically-paginate-posts' ), array( $this, 'settings_field_paging_type' ), 'reading', 'autopaging' );
}
/**
* Render post types options.
*
* @uses get_post_types, get_option, esc_attr, checked, esc_html
* @return void
*/
public function settings_field_post_types() {
// Get all public post types.
$post_types = get_post_types(
array(
'public' => true,
),
'objects'
);
unset( $post_types['attachment'] );
// Current settings.
$current_types = get_option( $this->option_name_post_types, $this->post_types_default );
// Output checkboxes.
foreach ( $post_types as $post_type => $atts ) :
?>
<input type="checkbox" name="<?php echo esc_attr( $this->option_name_post_types ); ?>[]" id="post-type-<?php echo esc_attr( $post_type ); ?>" value="<?php echo esc_attr( $post_type ); ?>"<?php checked( in_array( $post_type, $current_types ) ); ?> /> <label for="post-type-<?php echo esc_attr( $post_type ); ?>"><?php echo esc_html( $atts->label ); ?></label><br />
<?php
endforeach;
}
/**
* Sanitize post type inputs.
*
* @param array $post_types_checked Selected post types to sanitize.
* @uses get_post_types
* @return array
*/
public function sanitize_supported_post_types( $post_types_checked ) {
$post_types_sanitized = array();
// Ensure that only existing, public post types are submitted as valid options.
if ( is_array( $post_types_checked ) && ! empty( $post_types_checked ) ) {
// Get all public post types.
$post_types = get_post_types(
array(
'public' => true,
)
);
unset( $post_types['attachment'] );
// Check input post types against those registered with WordPress and made available to this plugin.
foreach ( $post_types_checked as $post_type ) {
if ( array_key_exists( $post_type, $post_types ) ) {
$post_types_sanitized[] = $post_type;
}
}
}
return $post_types_sanitized;
}
/**
* Render option to choose paging type and options for that type.
*
* @uses get_option()
* @uses esc_attr()
* @uses checked()
* @return void
*/
public function settings_field_paging_type() {
$paging_type = get_option( $this->option_name_paging_type, $this->paging_type_default );
if ( ! in_array( $paging_type, $this->paging_types_allowed ) ) {
$paging_type = $this->paging_type_default;
}
$labels = array(
'pages' => __( 'Total number of pages:', 'automatically-paginate-posts' ),
'words' => __( 'Approximate words per page:', 'automatically-paginate-posts' ),
);
foreach ( $this->paging_types_allowed as $type ) :
$func = 'settings_field_num_' . $type;
?>
<p>
<input type="radio" name="<?php echo esc_attr( $this->option_name_paging_type ); ?>" id="autopaging-type-<?php echo esc_attr( $type ); ?>" value="<?php echo esc_attr( $type ); ?>"<?php checked( $type, $paging_type ); ?> />
<label for="autopaging-type-<?php echo esc_attr( $type ); ?>">
<?php echo esc_html( $labels[ $type ] ); ?>
<?php $this->{$func}(); ?>
</label>
</p>
<br />
<?php
endforeach;
}
/**
* Validate chosen paging type against allowed values.
*
* @param string $type Selected paging type.
* @return string
*/
public function sanitize_paging_type( $type ) {
return in_array( $type, $this->paging_types_allowed, true ) ? $type : $this->paging_type_default;
}
/**
* Render dropdown for choosing number of pages to break content over.
*
* @uses get_option, apply_filters, esc_attr, selected
* @return void
*/
public function settings_field_num_pages() {
$num_pages = get_option( $this->option_name_num_pages, $this->num_pages_default );
$max_pages = apply_filters( 'autopaging_max_num_pages', 10 );
?>
<select name="<?php echo esc_attr( $this->option_name_num_pages ); ?>">
<?php for ( $i = 2; $i <= $max_pages; $i++ ) : ?>
<option value="<?php echo intval( $i ); ?>"<?php selected( (int) $i, (int) $num_pages ); ?>><?php echo intval( $i ); ?></option>
<?php endfor; ?>
</select>
<?php
}
/**
* Sanitize number of pages input.
*
* @param int $num_pages Number of pages to split to.
* @uses apply_filters
* @return int
*/
public function sanitize_num_pages( $num_pages ) {
return max( 2, min( intval( $num_pages ), apply_filters( 'autopaging_max_num_pages', 10 ) ) );
}
/**
* Render input field for specifying approximate number of words each page should contain.
*
* @uses get_option, apply_filters, esc_attr, selected
* @return void
*/
public function settings_field_num_words() {
$num_words = apply_filters( 'autopaging_num_words', get_option( $this->option_name_num_words ) )
?>
<input
name="<?php echo esc_attr( $this->option_name_num_words ); ?>"
value="<?php echo esc_attr( $num_words ); ?>"
class="small-text"
type="number"
step="1"
min="1"
/>
<p class="description"><?php esc_html_e( 'If chosen, each page will contain approximately this many words, depending on paragraph lengths.', 'automatically-paginate-posts' ); ?></p>
<?php
}
/**
* Sanitize number of words input. No fewer than 10 by default, filterable by `autopaging_max_num_words`.
*
* @param int $num_words Number of words to split on.
* @uses apply_filters
* @return int
*/
public function sanitize_num_words( $num_words ) {
$num_words = absint( $num_words );
if ( ! $num_words ) {
return 0;
}
return max( $num_words, apply_filters( 'autopaging_min_num_words', 10 ) );
}
/**
* Add autopaging metabox.
*
* @uses add_metabox, __
* @action add_meta_box
* @return void
*/
public function action_add_meta_boxes() {
foreach ( $this->post_types as $post_type ) {
if (
function_exists( 'use_block_editor_for_post_type' ) &&
use_block_editor_for_post_type( $post_type )
) {
continue;
}
add_meta_box( 'autopaging', __( 'Autopaging', 'automatically-paginate-posts' ), array( $this, 'meta_box_autopaging' ), $post_type, 'side' );
}
}
/**
* Render autopaging metabox.
*
* @param object $post Post object.
* @uses esc_attr, checked, _e, __, wp_nonce_field
* @return void
*/
public function meta_box_autopaging( $post ) {
?>
<p>
<input type="checkbox" name="<?php echo esc_attr( $this->meta_key_disable_autopaging ); ?>" id="<?php echo esc_attr( $this->meta_key_disable_autopaging ); ?>_checkbox" value="1"<?php checked( (bool) get_post_meta( $post->ID, $this->meta_key_disable_autopaging, true ) ); ?> />
<label for="<?php echo esc_attr( $this->meta_key_disable_autopaging ); ?>_checkbox">
<?php esc_html_e( 'Disable autopaging for this post?', 'automatically-paginate-posts' ); ?>
</label>
</p>
<p class="description"><?php esc_html__( 'Check the box above to prevent this post from automatically being split over multiple pages.', 'automatically-paginate-posts' ); ?></p>
<p class="description">
<?php
printf(
/* translators: 1. Quicktag code example. */
esc_html__(
'Note that if the %1$s Quicktag is used to manually page this post, automatic paging won\'t be applied, regardless of the setting above.',
'automatically-paginate-posts'
),
// No need to escape a class constant.
// phpcs:ignore WordPress.Security.EscapeOutput.OutputNotEscaped
'<code>' . htmlentities( static::QUICKTAG, ENT_QUOTES ) . '</code>'
);
?>
</p>
<?php
wp_nonce_field( $this->meta_key_disable_autopaging, $this->meta_key_disable_autopaging . '_wpnonce' );
}
/**
* Save autopaging metabox.
*
* @param int $post_id Post ID.
* @uses DOING_AUTOSAVE, wp_verify_nonce, update_post_meta, delete_post_meta
* @action save_post
* @return null
*/
public function action_save_post( $post_id ) {
if ( defined( 'DOING_AUTOSAVE' ) && DOING_AUTOSAVE ) {
return;
}
if (
function_exists( 'use_block_editor_for_post' )
&& use_block_editor_for_post( $post_id )
) {
return;
}
if ( isset( $_POST[ $this->meta_key_disable_autopaging . '_wpnonce' ] ) && wp_verify_nonce( $_POST[ $this->meta_key_disable_autopaging . '_wpnonce' ], $this->meta_key_disable_autopaging ) ) {
$disable = isset( $_POST[ $this->meta_key_disable_autopaging ] );
if ( $disable ) {
update_post_meta( $post_id, $this->meta_key_disable_autopaging, true );
} else {
delete_post_meta( $post_id, $this->meta_key_disable_autopaging );
}
}
}
/**
* Automatically page posts by injecting <!--nextpage--> Quicktag.
* Only applied if the post type matches specified options and post doesn't already contain the Quicktag.
*
* @param array $posts Array of posts retrieved by WP_Query.
* @uses is_admin, get_post_meta, absint, apply_filters
* @filter the_posts
* @return array
*/
public function filter_the_posts( $posts ) {
if ( is_admin() ) {
return $posts;
}
$paging_type = get_option(
$this->option_name_paging_type,
$this->paging_type_default
);
foreach ( $posts as &$the_post ) {
if (
! in_array(
$the_post->post_type,
$this->post_types,
true
)
) {
continue;
}
if (
preg_match(
'#' . static::QUICKTAG . '#i',
$the_post->post_content
)
) {
continue;
}
if (
(bool) get_post_meta(
$the_post->ID,
$this->meta_key_disable_autopaging,
true
)
) {
continue;
}
$num_pages = absint(
apply_filters(
'autopaging_num_pages',
absint( $this->num_pages ),
$the_post
)
);
$num_words = absint(
apply_filters(
'autopaging_num_words',
absint( $this->num_words ),
$the_post
)
);
if ( $num_pages < 2 && empty( $num_words ) ) {
continue;
}
if (
function_exists( 'has_blocks' )
&& has_blocks( $the_post )
) {
$this->filter_block_editor_post(
$the_post,
$paging_type,
$num_words,
$num_pages
);
} else {
$this->filter_classic_editor_post(
$the_post,
$paging_type,
$num_words,
$num_pages
);
}
}
return $posts;
}
/**
* Add pagination Quicktag to post authored in the Classic Editor.
*
* @param WP_Post|object $the_post Post object.
* @param string $paging_type How to split post.
* @param int $num_words Number of words to split on.
* @param int $num_pages Number of pages to split to.
* @return void
*/
protected function filter_classic_editor_post(
&$the_post,
$paging_type,
$num_words,
$num_pages
) {
// Start with post content, but alias to protect the raw content.
$content = $the_post->post_content;
// Normalize post content to simplify paragraph counting and automatic paging. Accounts for content that hasn't been cleaned up by TinyMCE.
$content = preg_replace( '#<p>(.+?)</p>#i', "$1\r\n\r\n", $content );
$content = preg_replace( '#<br(\s*/)?>#i', "\r\n", $content );
$content = explode( "\r\n\r\n", $content );
// Count number of paragraphs content was exploded to.
$count = count( $content );
// Nothing to do, goodbye.
if ( $count <= 1 ) {
return;
}
switch ( $paging_type ) {
case 'words':
$word_counter = 0;
// Count words per paragraph and break after the paragraph that exceeds the set threshold.
foreach ( $content as $index => $paragraph ) {
$word_counter += mb_strlen(
wp_strip_all_tags(
$paragraph
)
);
if ( $word_counter >= $num_words ) {
$content[ $index ] .= static::QUICKTAG;
$word_counter = 0;
}
}
// Prevent the last page from being empty.
$last_page = array_pop( $content );
if (
static::QUICKTAG ===
substr(
$last_page,
- static::QUICKTAG_LENGTH
)
) {
$content[] = substr(
$last_page,
0,
strlen( $last_page ) - static::QUICKTAG_LENGTH
);
} else {
$content[] = $last_page;
}
break;
case 'pages':
default:
$frequency = $this->get_insertion_frequency_by_pages(
$count,
$num_pages
);
$i = 1;
// Loop through content pieces and append Quicktag as is appropriate.
foreach ( $content as $key => $value ) {
if ( $this->is_at_end_for_pages( $key, $count ) ) {
break;
}
if (
$this->is_insertion_point_for_pages(
$key,
$i,
$frequency
)
) {
$content[ $key ] .= static::QUICKTAG;
$i++;
}
}
break;
}
// Reunite content.
$content = implode( "\r\n\r\n", $content );
// And, overwrite the original content.
$the_post->post_content = $content;
}
/**
* Add pagination block to post authored in the Block Editor.
*
* @param WP_Post $the_post Post object.
* @param string $paging_type How to split post.
* @param int $num_words Number of words to split on.
* @param int $num_pages Number of pages to split to.
* @return void
*/
protected function filter_block_editor_post(
&$the_post,
$paging_type,
$num_words,
$num_pages
) {
$blocks = parse_blocks( $the_post->post_content );
$new_blocks = array();
switch ( $paging_type ) {
case 'words':
$word_count = 0;
foreach ( $blocks as $block ) {
$new_blocks[] = $block;
if (
in_array(
$block['blockName'],
$this->supported_block_types_for_word_counts,
true
)
) {
$word_count += mb_strlen(
trim(
wp_strip_all_tags(
$block['innerHTML']
)
)
);
if ( $word_count >= $num_words ) {
$new_blocks[] = $this->get_parsed_nextpage_block();
$word_count = 0;
}
}
}
$last_block = array_pop( $new_blocks );
if ( $this->get_parsed_nextpage_block() !== $last_block ) {
$new_blocks[] = $last_block;
}
break;
case 'pages':
default:
$count = count( $blocks );
$frequency = $this->get_insertion_frequency_by_pages(
$count,
$num_pages
);
$i = 1;
foreach ( $blocks as $key => $block ) {
$new_blocks[] = $block;
if ( $this->is_at_end_for_pages( $key, $count ) ) {
break;
}
if (
$this->is_insertion_point_for_pages(
$key,
$i,
$frequency
)
) {
$new_blocks[] = $this->get_parsed_nextpage_block();
$i++;
}
}
break;
}
$the_post->post_content = serialize_blocks( $new_blocks );
}
/**
* Determine after how many paragraphs a page break should be inserted.
*
* @param int $count Total number of paragraphs.
* @param int $num_pages Desired number of pages.
* @return int
*/
protected function get_insertion_frequency_by_pages( $count, $num_pages ) {
$frequency = (int) round( $count / $num_pages );
// If number of pages is greater than number of paragraphs, put each paragraph on its own page.
if ( $num_pages > $count ) {
$frequency = 1;
}
return $frequency;
}
/**
* Determine if more page breaks should be inserted.
*
* @param int $key Current position in array of blocks.
* @param int $count Total number of paragraphs.
* @return bool
*/
protected function is_at_end_for_pages( $key, $count ) {
return ( $key + 1 ) === $count;
}
/**
* Determine if current loop iteration is where a page break is expected.
*
* @param int $loop_key Current position in array of blocks.
* @param int $insertion_iterator Current number of page breaks inserted.
* @param int $insertion_frequency After this many blocks a should break be
* inserted.
* @return bool
*/
protected function is_insertion_point_for_pages(
$loop_key,
$insertion_iterator,
$insertion_frequency
) {
return ( $loop_key + 1 ) ===
( $insertion_iterator * $insertion_frequency );
}
/**
* Create parsed representation of block for insertion in list of post's
* blocks.
*
* @return array
*/
protected function get_parsed_nextpage_block() {
static $block;
if ( ! $block ) {
$_block = parse_blocks(
'<!-- wp:nextpage -->
' . static::QUICKTAG . '
<!-- /wp:nextpage -->'
);
$block = array_shift( $_block );
}
return $block;
}
}
new Automatically_Paginate_Posts();
?>