<?php
/**
 * Server-side rendering of the `core/post-time-to-read` block.
 *
 * @package WordPress
 */

/**
 * Counts words or characters in a provided text string.
 *
 * This function currently employs an array of regular expressions
 * to parse HTML and count words, which may result in inaccurate
 * word counts. However, it is designed primarily to agree with the
 * corresponding JavaScript function.
 *
 * Any improvements in the word counting, for example with the HTML API
 * and {@see \IntlBreakIterator::createWordInstance()} should coordinate
 * with changes to the JavaScript implementation to ensure consistency
 * between the editor and the rendered page.
 *
 * @since 6.9.0
 *
 * @param string $text Text to count elements in.
 * @param string $type The type of count. Accepts 'words', 'characters_excluding_spaces', or 'characters_including_spaces'.
 *
 * @return string The rendered word count.
 */
function block_core_post_time_to_read_word_count( $text, $type ) {
    $settings = array(
        'html_regexp'                        => '/<\/?[a-z][^>]*?>/i',
        'html_comment_regexp'                => '/<!--[\s\S]*?-->/',
        'space_regexp'                       => '/&nbsp;|&#160;/i',
        'html_entity_regexp'                 => '/&\S+?;/',
        'connector_regexp'                   => "/--|\x{2014}/u",
        'remove_regexp'                      => "/[\x{0021}-\x{0040}\x{005B}-\x{0060}\x{007B}-\x{007E}\x{0080}-\x{00BF}\x{00D7}\x{00F7}\x{2000}-\x{2BFF}\x{2E00}-\x{2E7F}]/u",
        'astral_regexp'                      => "/[\x{010000}-\x{10FFFF}]/u",
        'words_regexp'                       => '/\S\s+/u',
        'characters_excluding_spaces_regexp' => '/\S/u',
        'characters_including_spaces_regexp' => "/[^\f\n\r\t\v\x{00AD}\x{2028}\x{2029}]/u",
    );

    $count = 0;

    if ( '' === trim( $text ) ) {
        return $count;
    }

    // Sanitize type to one of three possibilities: 'words', 'characters_excluding_spaces' or 'characters_including_spaces'.
    if ( 'characters_excluding_spaces' !== $type && 'characters_including_spaces' !== $type ) {
        $type = 'words';
    }

    $text .= "\n";

    // Replace all HTML with a new-line.
    $text = preg_replace( $settings['html_regexp'], "\n", $text );

    // Remove all HTML comments.
    $text = preg_replace( $settings['html_comment_regexp'], '', $text );

    // If a shortcode regular expression has been provided use it to remove shortcodes.
    if ( ! empty( $settings['shortcodes_regexp'] ) ) {
        $text = preg_replace( $settings['shortcodes_regexp'], "\n", $text );
    }

    // Normalize non-breaking space to a normal space.
    $text = preg_replace( $settings['space_regexp'], ' ', $text );

    if ( 'words' === $type ) {
        // Remove HTML Entities.
        $text = preg_replace( $settings['html_entity_regexp'], '', $text );

        // Convert connectors to spaces to count attached text as words.
        $text = preg_replace( $settings['connector_regexp'], ' ', $text );

        // Remove unwanted characters.
        $text = preg_replace( $settings['remove_regexp'], '', $text );
    } else {
        // Convert HTML Entities to "a".
        $text = preg_replace( $settings['html_entity_regexp'], 'a', $text );

        // Remove surrogate points.
        $text = preg_replace( $settings['astral_regexp'], 'a', $text );
    }

    // Match with the selected type regular expression to count the items.
    return (int) preg_match_all( $settings[ $type . '_regexp' ], $text );
}

/**
 * Renders the `core/post-time-to-read` block on the server.
 *
 * @since 6.9.0
 *
 * @param  array    $attributes Block attributes.
 * @param  string   $content    Block default content.
 * @param  WP_Block $block      Block instance.
 * @return string Returns the rendered post author name block.
 */
function render_block_core_post_time_to_read( $attributes, $content, $block ) {
    if ( ! isset( $block->context['postId'] ) ) {
        return '';
    }

    $content              = get_the_content();
    $average_reading_rate = $attributes['averageReadingSpeed'] ?? 189;

    $display_mode = $attributes['displayMode'] ?? 'time';

    $word_count_type = wp_get_word_count_type();
    $total_words     = block_core_post_time_to_read_word_count( $content, $word_count_type );

    $parts = array();

    // Add "time to read" part, if enabled.
    if ( 'time' === $display_mode ) {
        if ( ! empty( $attributes['displayAsRange'] ) ) {
            // Calculate faster reading rate with 20% speed = lower minutes,
            // and slower reading rate with 20% speed = higher minutes.
            $min_minutes = max( 1, (int) round( $total_words / $average_reading_rate * 0.8 ) );
            $max_minutes = max( 1, (int) round( $total_words / $average_reading_rate * 1.2 ) );
            if ( $min_minutes === $max_minutes ) {
                $max_minutes = $min_minutes + 1;
            }
            /* translators: 1: minimum minutes, 2: maximum minutes to read the post. */
            $time_string = sprintf(
                /* translators: 1: minimum minutes, 2: maximum minutes to read the post. */
                _x( '%1$s–%2$s minutes', 'Range of minutes to read' ),
                $min_minutes,
                $max_minutes
            );
        } else {
            $minutes_to_read = max( 1, (int) round( $total_words / $average_reading_rate ) );
            $time_string     = sprintf(
                /* translators: %s: the number of minutes to read the post. */
                _n( '%s minute', '%s minutes', $minutes_to_read ),
                $minutes_to_read
            );
        }
        $parts[] = $time_string;
    }

    // Add "word count" part, if enabled.
    if ( 'words' === $display_mode ) {
        $word_count_string = 'words' === $word_count_type ? sprintf(
            /* translators: %s: the number of words in the post. */
            _n( '%s word', '%s words', $total_words ),
            number_format_i18n( $total_words )
        ) : sprintf(
            /* translators: %s: the number of characters in the post. */
            _n( '%s character', '%s characters', $total_words ),
            number_format_i18n( $total_words )
        );
        $parts[] = $word_count_string;
    }

    $display_string = implode( '<br>', $parts );

    $align_class_name = empty( $attributes['textAlign'] ) ? '' : "has-text-align-{$attributes['textAlign']}";

    $wrapper_attributes = get_block_wrapper_attributes( array( 'class' => $align_class_name ) );

    return sprintf(
        '<div %1$s>%2$s</div>',
        $wrapper_attributes,
        $display_string
    );
}


/**
 * Registers the `core/post-time-to-read` block on the server.
 *
 * @since 6.9.0
 */
function register_block_core_post_time_to_read() {
    register_block_type_from_metadata(
        __DIR__ . '/post-time-to-read',
        array(
            'render_callback' => 'render_block_core_post_time_to_read',
        )
    );
}

add_action( 'init', 'register_block_core_post_time_to_read' );