amp-post-template-functions.php

<?php
/**
 * Callbacks for adding content to an AMP template.
 *
 * @package AMP
 */

/**
 * Register hooks.
 *
 * @internal
 */
function amp_post_template_init_hooks() {
	if ( version_compare( strtok( get_bloginfo( 'version' ), '-' ), '5.7', '>=' ) ) {
		add_action( 'amp_post_template_head', 'wp_robots' );
	} else {
		add_action( 'amp_post_template_head', 'noindex' );
	}
	add_action( 'amp_post_template_head', 'amp_post_template_add_title' );
	add_action( 'amp_post_template_head', 'amp_post_template_add_canonical' );
	add_action( 'amp_post_template_head', 'amp_post_template_add_fonts' );
	add_action( 'amp_post_template_head', 'amp_add_generator_metadata' );
	add_action( 'amp_post_template_head', 'wp_generator' );
	add_action( 'amp_post_template_head', 'amp_post_template_add_block_styles' );
	add_action( 'amp_post_template_head', 'amp_post_template_add_default_styles' );
	add_action( 'amp_post_template_css', 'amp_post_template_add_styles', 99 );
	add_action( 'amp_post_template_footer', 'amp_post_template_add_analytics_data' );

	add_action( 'admin_bar_init', [ AMP_Theme_Support::class, 'init_admin_bar' ] );
	add_action( 'amp_post_template_footer', 'wp_admin_bar_render' );

	// Printing scripts here is done primarily for the benefit of the admin bar. Note that wp_enqueue_scripts() is not called.
	add_action( 'amp_post_template_head', 'wp_print_head_scripts' );
	add_action( 'amp_post_template_footer', 'wp_print_footer_scripts' );
}

/**
 * Add title.
 *
 * @internal
 *
 * @param AMP_Post_Template $amp_template template.
 */
function amp_post_template_add_title( $amp_template ) {
	?>
	<title><?php echo esc_html( $amp_template->get( 'document_title' ) ); ?></title>
	<?php
}

/**
 * Add canonical link.
 *
 * @internal
 *
 * @param AMP_Post_Template $amp_template Template.
 */
function amp_post_template_add_canonical( $amp_template ) {
	?>
	<link rel="canonical" href="<?php echo esc_url( $amp_template->get( 'canonical_url' ) ); ?>" />
	<?php
}

/**
 * Print fonts.
 *
 * @internal
 *
 * @param AMP_Post_Template $amp_template Template.
 */
function amp_post_template_add_fonts( $amp_template ) {
	$font_urls = $amp_template->get( 'font_urls', [] );
	foreach ( $font_urls as $url ) {
		printf( '<link rel="stylesheet" href="%s">', esc_url( esc_url( $url ) ) ); // phpcs:ignore WordPress.WP.EnqueuedResources.NonEnqueuedStylesheet
	}
}

/**
 * Add block styles for core blocks and third-party blocks.
 *
 * @internal
 *
 * @since 1.5.0
 */
function amp_post_template_add_block_styles() {
	add_theme_support( 'wp-block-styles' );
	if ( function_exists( 'wp_common_block_scripts_and_styles' ) ) {
		wp_common_block_scripts_and_styles();
	}

	// Note that this will also print the admin-bar styles since WP_Admin_Bar::initialize() has been called.
	wp_styles()->do_items();
}

/**
 * Print default styles.
 *
 * @since 2.0.1
 * @internal
 */
function amp_post_template_add_default_styles() {
	wp_print_styles( 'amp-default' );
}

/**
 * Print styles.
 *
 * @internal
 *
 * @param AMP_Post_Template $amp_template Template.
 */
function amp_post_template_add_styles( $amp_template ) {
	$stylesheets = $amp_template->get( 'post_amp_stylesheets' );
	if ( ! empty( $stylesheets ) ) {
		echo '/* Inline stylesheets */' . PHP_EOL; // phpcs:ignore WordPress.Security.EscapeOutput.OutputNotEscaped
		echo implode( '', $stylesheets ); // phpcs:ignore WordPress.Security.EscapeOutput.OutputNotEscaped
	}

	$styles = $amp_template->get( 'post_amp_styles' );
	if ( ! empty( $styles ) ) {
		echo '/* Inline styles */' . PHP_EOL; // phpcs:ignore WordPress.Security.EscapeOutput.OutputNotEscaped
		foreach ( $styles as $selector => $declarations ) {
			$declarations = implode( ';', $declarations ) . ';';
			printf( '%1$s{%2$s}', $selector, $declarations ); // phpcs:ignore WordPress.Security.EscapeOutput.OutputNotEscaped
		}
	}
}

/**
 * Add custom analytics.
 *
 * This is currently only used for legacy AMP post templates.
 *
 * @since 0.5
 * @see amp_get_analytics()
 * @internal
 *
 * @param array $analytics Analytics.
 * @return array Analytics.
 */
function amp_add_custom_analytics( $analytics = [] ) {
	$analytics = amp_get_analytics( $analytics );

	/**
	 * Add amp-analytics tags.
	 *
	 * This filter allows you to easily insert any amp-analytics tags without needing much heavy lifting.
	 * This filter should be used to alter entries for legacy AMP templates.
	 *
	 * @since 0.4
	 *
	 * @param array   $analytics An associative array of the analytics entries we want to output. Each array entry must have a unique key, and the value should be an array with the following keys: `type`, `attributes`, `script_data`. See readme for more details.
	 * @param WP_Post $post      The current post.
	 */
	$analytics = apply_filters( 'amp_post_template_analytics', $analytics, get_queried_object() );

	return $analytics;
}

/**
 * Print analytics data.
 *
 * @internal
 *
 * @since 0.3.2
 */
function amp_post_template_add_analytics_data() {
	$analytics = amp_add_custom_analytics();
	amp_print_analytics( $analytics );
}