<?php

/**

 * Server-side rendering of the `core/post-comments-form` block.

 *

 * @package WordPress

 */

/**

 * Renders the `core/post-comments-form` block on the server.

 *

 * @param array    $attributes Block attributes.

 * @param string   $content    Block default content.

 * @param WP_Block $block      Block instance.

 * @return string Returns the filtered post comments form for the current post.

 */

function render_block_core_post_comments_form( $attributes, $content, $block ) {

	if ( ! isset( $block->context['postId'] ) ) {

		return '';

	}

	if ( post_password_required( $block->context['postId'] ) ) {

		return;

	}

	$classes = 'comment-respond'; // See comment further below.

	if ( isset( $attributes['textAlign'] ) ) {

		$classes .= ' has-text-align-' . $attributes['textAlign'];

	}

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

	add_filter( 'comment_form_defaults', 'post_comments_form_block_form_defaults' );

	ob_start();

	comment_form( array(), $block->context['postId'] );

	$form = ob_get_clean();

	remove_filter( 'comment_form_defaults', 'post_comments_form_block_form_defaults' );

	// We use the outermost wrapping `<div />` returned by `comment_form()`

	// which is identified by its default classname `comment-respond` to inject

	// our wrapper attributes. This way, it is guaranteed that all styling applied

	// to the block is carried along when the comment form is moved to the location

	// of the 'Reply' link that the user clicked by Core's `comment-reply.js` script.

	$form = str_replace( 'class="comment-respond"', $wrapper_attributes, $form );

	// Enqueue the comment-reply script.

	wp_enqueue_script( 'comment-reply' );

	return $form;

}

/**

 * Registers the `core/post-comments-form` block on the server.

 */

function register_block_core_post_comments_form() {

	register_block_type_from_metadata(

		__DIR__ . '/post-comments-form',

		array(

			'render_callback' => 'render_block_core_post_comments_form',

		)

	);

}

add_action( 'init', 'register_block_core_post_comments_form' );

/**

 * Use the button block classes for the form-submit button.

 *

 * @param array $fields The default comment form arguments.

 *

 * @return array Returns the modified fields.

 */

function post_comments_form_block_form_defaults( $fields ) {

	if ( wp_is_block_theme() ) {

		$fields['submit_button'] = '<input name="%1$s" type="submit" id="%2$s" class="%3$s wp-block-button__link" value="%4$s" />';

		$fields['submit_field']  = '<p class="form-submit wp-block-button">%1$s %2$s</p>';

	}

	return $fields;

}