<?php

function gtm_render_block_post_navigation_link( $attr, $content, $block ) {
	if ( $attr['type'] == 'next' ) {
		$post         = get_next_post();
		$default_icon = 'gtm-basic-icon-chevron-right';

	} else {
		$post         = get_previous_post();
		$default_icon = 'gtm-basic-icon-chevron-left';
	}

	$block_content = '';

	if ( ! empty( $post ) ) {
		if ( ! empty( $attr['enableIcon'] ) ) {
			if ( ! empty( $attr['enableIconLink'] ) ) {
				$open_tag  = sprintf( '<a class="wp-block-gtm-post-navigation-link__icon" href="%1$s" href="%1$s">', esc_url( get_permalink( $post->ID ) ) );
				$close_tag = '</a>';
			} else {
				$open_tag  = '<span class="wp-block-gtm-post-navigation-link__icon">';
				$close_tag = '</span>';
			}

			$block_content .= $open_tag;
			$block_content .= '<i class="gtm-icon ' . ( ! empty( $attr['icon'] ) ? $attr['icon'] : $default_icon ) . '"></i>';
			$block_content .= $close_tag;
		}

		$block_content .= '<div class="wp-block-gtm-post-navigation-link__post">';
		if ( ! empty( $block->parsed_block['innerBlocks'] ) ) {
			foreach ( $block->parsed_block['innerBlocks'] as $inner_block ) {
				$block_content .= (
					new WP_Block(
						$inner_block,
						[
							'postType' => $post->post_type,
							'postId'   => $post->ID,
						]
					)
				)->render( ['dynamic' => true] );
			}
		}

		$block_content .= '</div>';

		$wrapper_attributes = get_block_wrapper_attributes( ['class' => ''] );

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

/**
 * Registers the `gtm/post-navigation-link` block on the server.
 */
function gtm_register_block_post_navigation_link() {
	gtm_register_block_type( 'post-navigation-link', [
		'render_callback'   => 'gtm_render_block_post_navigation_link',
		'skip_inner_blocks' => true,
	] );
}

add_action( 'init', 'gtm_register_block_post_navigation_link', 20 );

add_filter( 'gtm.BlockStyleCompiler.gtm/post-navigation-link', 'gtm_compile_block_css_post_navigation_link', 10, 3 );
function gtm_compile_block_css_post_navigation_link( $output, $attributes, $blockName ) {
	$block_style = ['classes' => [], 'style' => []];

	$block_style['classes'][] = 'gtm-block';
	$block_style['classes'][] = "gtm-is-post-navigation-link-type-{$attributes['type']}";
	$block_style['classes'][] = "gtm-has-post-navigation-position-{$attributes['iconPosition']}";

	if ( $attributes['enableRtlIcon'] ) {
		$block_style['classes'][] = 'gtm-is-post-navigation-link-rtl';
	}

	if ( $attributes['enableIcon'] ) {
		gtm_css_compileCssVar( $block_style, "post-navigation-link-icon-padding", gtm_css_parseResponsiveBoxProps( $attributes['iconPadding'] ) );

		gtm_css_compileCssVar( $block_style, "post-navigation-link-icon-size", $attributes['iconSize'] );

		gtm_css_compileCssVar( $block_style, "post-navigation-link-icon-spacing", gtm_css_parseSpacingValue( $attributes['iconSpacing'] ) );

		gtm_css_compileCssVar( $block_style, "post-navigation-link-icon-radius", gtm_css_parseBorderRadiusValue( $attributes['iconRadius'] ) );

		gtm_css_compileCssVar( $block_style, "post-navigation-link-icon-color", gtm_css_parseColorValue( $attributes['iconColor'] ) );

		gtm_css_compileCssVar( $block_style, "post-navigation-link-icon-bg", gtm_css_parseColorValue( $attributes['iconBg'] ) );
	}

	// Apply to output
	$block_style['style'] = ['{{BLOCK}}' => $block_style['style']];

	return [
		'classes' => array_merge( $output['classes'], $block_style['classes'] ),
		'style'   => array_replace_recursive( $output['style'], $block_style['style'] ),
	];
}