<?php 
/** 
 * Server-side rendering of the `core/calendar` block. 
 * 
 * @package WordPress 
 */ 
 
/** 
 * Renders the `core/calendar` block on server. 
 * 
 * @since 5.2.0 
 * 
 * @global int $monthnum. 
 * @global int $year. 
 * 
 * @param array $attributes The block attributes. 
 * 
 * @return string Returns the block content. 
 */ 
function render_block_core_calendar( $attributes ) { 
    global $monthnum, $year; 
 
    // Calendar shouldn't be rendered 
    // when there are no published posts on the site. 
    if ( ! block_core_calendar_has_published_posts() ) { 
        if ( is_user_logged_in() ) { 
            return '<div>' . __( 'The calendar block is hidden because there are no published posts.' ) . '</div>'; 
        } 
        return ''; 
    } 
 
    $previous_monthnum = $monthnum; 
    $previous_year     = $year; 
 
    if ( isset( $attributes['month'] ) && isset( $attributes['year'] ) ) { 
        $permalink_structure = get_option( 'permalink_structure' ); 
        if ( 
            str_contains( $permalink_structure, '%monthnum%' ) && 
            str_contains( $permalink_structure, '%year%' ) 
        ) { 
            $monthnum = $attributes['month']; 
            $year     = $attributes['year']; 
        } 
    } 
 
    $color_block_styles = array(); 
 
    // Text color. 
    $preset_text_color          = array_key_exists( 'textColor', $attributes ) ? "var:preset|color|{$attributes['textColor']}" : null; 
    $custom_text_color          = $attributes['style']['color']['text'] ?? null; 
    $color_block_styles['text'] = $preset_text_color ? $preset_text_color : $custom_text_color; 
 
    // Background Color. 
    $preset_background_color          = array_key_exists( 'backgroundColor', $attributes ) ? "var:preset|color|{$attributes['backgroundColor']}" : null; 
    $custom_background_color          = $attributes['style']['color']['background'] ?? null; 
    $color_block_styles['background'] = $preset_background_color ? $preset_background_color : $custom_background_color; 
 
    // Generate color styles and classes. 
    $styles        = wp_style_engine_get_styles( array( 'color' => $color_block_styles ), array( 'convert_vars_to_classnames' => true ) ); 
    $inline_styles = empty( $styles['css'] ) ? '' : sprintf( ' style="%s"', esc_attr( $styles['css'] ) ); 
    $classnames    = empty( $styles['classnames'] ) ? '' : ' ' . esc_attr( $styles['classnames'] ); 
    if ( isset( $attributes['style']['elements']['link']['color']['text'] ) ) { 
        $classnames .= ' has-link-color'; 
    } 
    // Apply color classes and styles to the calendar. 
    $calendar = str_replace( '<table', '<table' . $inline_styles, get_calendar( true, false ) ); 
    $calendar = str_replace( 'class="wp-calendar-table', 'class="wp-calendar-table' . $classnames, $calendar ); 
 
    $wrapper_attributes = get_block_wrapper_attributes(); 
    $output             = sprintf( 
        '<div %1$s>%2$s</div>', 
        $wrapper_attributes, 
        $calendar 
    ); 
 
    $monthnum = $previous_monthnum; 
    $year     = $previous_year; 
 
    return $output; 
} 
 
/** 
 * Registers the `core/calendar` block on server. 
 * 
 * @since 5.2.0 
 */ 
function register_block_core_calendar() { 
    register_block_type_from_metadata( 
        __DIR__ . '/calendar', 
        array( 
            'render_callback' => 'render_block_core_calendar', 
        ) 
    ); 
} 
 
add_action( 'init', 'register_block_core_calendar' ); 
 
/** 
 * Returns whether or not there are any published posts. 
 * 
 * Used to hide the calendar block when there are no published posts. 
 * This compensates for a known Core bug: https://core.trac.wordpress.org/ticket/12016 
 * 
 * @since 5.9.0 
 * 
 * @return bool Has any published posts or not. 
 */ 
function block_core_calendar_has_published_posts() { 
    // Multisite already has an option that stores the count of the published posts. 
    // Let's use that for multisites. 
    if ( is_multisite() ) { 
        return 0 < (int) get_option( 'post_count' ); 
    } 
 
    // On single sites we try our own cached option first. 
    $has_published_posts = get_option( 'wp_calendar_block_has_published_posts', null ); 
    if ( null !== $has_published_posts ) { 
        return (bool) $has_published_posts; 
    } 
 
    // No cache hit, let's update the cache and return the cached value. 
    return block_core_calendar_update_has_published_posts(); 
} 
 
/** 
 * Queries the database for any published post and saves 
 * a flag whether any published post exists or not. 
 * 
 * @since 5.9.0 
 * 
 * @global wpdb $wpdb WordPress database abstraction object. 
 * 
 * @return bool Has any published posts or not. 
 */ 
function block_core_calendar_update_has_published_posts() { 
    global $wpdb; 
    $has_published_posts = (bool) $wpdb->get_var( "SELECT 1 as test FROM {$wpdb->posts} WHERE post_type = 'post' AND post_status = 'publish' LIMIT 1" ); 
    update_option( 'wp_calendar_block_has_published_posts', $has_published_posts ); 
    return $has_published_posts; 
} 
 
// We only want to register these functions and actions when 
// we are on single sites. On multi sites we use `post_count` option. 
if ( ! is_multisite() ) { 
    /** 
     * Handler for updating the has published posts flag when a post is deleted. 
     * 
     * @since 5.9.0 
     * 
     * @param int $post_id Deleted post ID. 
     */ 
    function block_core_calendar_update_has_published_post_on_delete( $post_id ) { 
        $post = get_post( $post_id ); 
 
        if ( ! $post || 'publish' !== $post->post_status || 'post' !== $post->post_type ) { 
            return; 
        } 
 
        block_core_calendar_update_has_published_posts(); 
    } 
 
    /** 
     * Handler for updating the has published posts flag when a post status changes. 
     * 
     * @since 5.9.0 
     * 
     * @param string  $new_status The status the post is changing to. 
     * @param string  $old_status The status the post is changing from. 
     * @param WP_Post $post       Post object. 
     */ 
    function block_core_calendar_update_has_published_post_on_transition_post_status( $new_status, $old_status, $post ) { 
        if ( $new_status === $old_status ) { 
            return; 
        } 
 
        if ( 'post' !== get_post_type( $post ) ) { 
            return; 
        } 
 
        if ( 'publish' !== $new_status && 'publish' !== $old_status ) { 
            return; 
        } 
 
        block_core_calendar_update_has_published_posts(); 
    } 
 
    add_action( 'delete_post', 'block_core_calendar_update_has_published_post_on_delete' ); 
    add_action( 'transition_post_status', 'block_core_calendar_update_has_published_post_on_transition_post_status', 10, 3 ); 
} 
 
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