functions.php

<?php
/**
 * AMP Compatible Theme functions and definitions
 *
 * @link https://developer.wordpress.org/themes/basics/theme-functions/
 *
 * @package AMP_Compatible_Theme
 */

if ( ! function_exists( 'amp_setup' ) ) :
/**
 * Sets up theme defaults and registers support for various WordPress features.
 *
 * Note that this function is hooked into the after_setup_theme hook, which
 * runs before the init hook. The init hook is too late for some features, such
 * as indicating support for post thumbnails.
 */
function amp_setup() {
	/*
	 * Make theme available for translation.
	 * Translations can be filed in the /languages/ directory.
	 * If you're building a theme based on AMP Compatible Theme, use a find and replace
	 * to change 'amp' to the name of your theme in all the template files.
	 */
	load_theme_textdomain( 'amp', get_template_directory() . '/languages' );

	// Add default posts and comments RSS feed links to head.
	add_theme_support( 'automatic-feed-links' );

	/*
	 * Let WordPress manage the document title.
	 * By adding theme support, we declare that this theme does not use a
	 * hard-coded <title> tag in the document head, and expect WordPress to
	 * provide it for us.
	 */
	add_theme_support( 'title-tag' );

	/*
	 * Enable support for Post Thumbnails on posts and pages.
	 *
	 * @link https://developer.wordpress.org/themes/functionality/featured-images-post-thumbnails/
	 * This is what is referred now to as Featured Images.
	 * If we want our theme to support adding feature images to posts and pages,
	 * this feature has to be explicitly supported.
	 */
	add_theme_support( 'post-thumbnails' );

	// This theme uses wp_nav_menu() in one location.
	// Here we just register the menu(s), which means we can
	// populate them via the customizer
	register_nav_menus( array(
		'primary' => esc_html__( 'Header', 'amp' ),
		'social' => esc_html__( 'Social', 'amp' ),
	) );

	/*
	 * Switch default core markup for search form, comment form, and comments
	 * to output valid HTML5.
	 */
	add_theme_support( 'html5', array(
		'search-form',
		'comment-form',
		'comment-list',
		'gallery',
		'caption',
	) );

	// Set up the WordPress core custom background feature.
	add_theme_support( 'custom-background', apply_filters( 'amp_custom_background_args', array(
		'default-color' => 'ffffff',
		'default-image' => '',
	) ) );

	// Add theme support for selective refresh for widgets.
	add_theme_support( 'customize-selective-refresh-widgets' );

	// Add theme support for custom logo
	add_theme_support('custom-logo', array(
		'width'=> 90,
		'height' => 90,
		'flex-width' => true,
	));

	// Add theme support for AMP
	add_theme_support( 'amp' );

}
endif;
add_action( 'after_setup_theme', 'amp_setup' );

/**
 * Register custom fonts.
 */
function amp_fonts_url() {
	$fonts_url = '';

	/**
	 * Translators: If there are characters in your language that are not
	 * supported by Source Sans Pro and PT Serif, translate this to 'off'. Do not translate
	 * into your own language.
	 */
	$source_sans_pro = _x( 'on', 'Source Pro Sans font: on or off', 'amp' );
	$pt_serif = _x( 'on', 'PT Serif font: on or off', 'amp' );
	$font_families = array();
	if ( 'off' !== $source_sans_pro ) {
		$font_families[] = 'Source Sans Pro:400,400i,700,900';
	}
	if ( 'off' !== $pt_serif ) {
		$font_families[] = 'PT Serif:400,400i,700,700i';
	}

	if (in_array( "on", array($source_sans_pro, $pt_serif) ) ) {
		$query_args = array(
			'family' => urlencode( implode( '|', $font_families ) ),
			'subset' => urlencode( 'latin,latin-ext' ),
		);

		$fonts_url = add_query_arg( $query_args, 'https://fonts.googleapis.com/css' );
	}

	return esc_url_raw( $fonts_url );
}

/**
 * Add preconnect for Google Fonts.
 *
 * @param array  $urls           URLs to print for resource hints.
 * @param string $relation_type  The relation type the URLs are printed.
 * @return array $urls           URLs to print for resource hints.
 */
function amp_resource_hints( $urls, $relation_type ) {
	if ( wp_style_is( 'amp-theme-fonts', 'queue' ) && 'preconnect' === $relation_type ) {
		$urls[] = array(
			'href' => 'https://fonts.gstatic.com',
			'crossorigin',
		);
	}

	return $urls;
}
/*
 * The wp_resource_hints is the place where all the resource
 * hints are given to the browser
 */
add_filter( 'wp_resource_hints', 'amp_resource_hints', 10, 2 );



/**
 * Set the content width in pixels, based on the theme's design and stylesheet.
 *
 * Priority 0 to make it available to lower priority callbacks.
 *
 * @global int $content_width
 */
function amp_content_width() {
	$GLOBALS['content_width'] = apply_filters( 'amp_content_width', 640 );
}
add_action( 'after_setup_theme', 'amp_content_width', 0 );

/**
 * Register widget area.
 *
 * @link https://developer.wordpress.org/themes/functionality/sidebars/#registering-a-sidebar
 */
function amp_widgets_init() {
	register_sidebar( array(
		'name'          => esc_html__( 'Sidebar', 'amp' ),
		'id'            => 'sidebar-1',
		'description'   => esc_html__( 'Add widgets here.', 'amp' ),
		'before_widget' => '<section id="%1$s" class="widget %2$s">',
		'after_widget'  => '</section>',
		'before_title'  => '<h2 class="widget-title">',
		'after_title'   => '</h2>',
	) );
	// For custom page layout
	register_sidebar( array(
		'name'          => esc_html__( 'Page Sidebar', 'amp' ),
		'id'            => 'sidebar-2',
		'description'   => esc_html__( 'Add page widgets here.', 'amp' ),
		'before_widget' => '<section id="%1$s" class="widget %2$s">',
		'after_widget'  => '</section>',
		'before_title'  => '<h2 class="widget-title">',
		'after_title'   => '</h2>',
	) );
}
add_action( 'widgets_init', 'amp_widgets_init' );

/**
 * Enqueue scripts and styles.
 */
function amp_scripts() {
	// enqueue Google Fonts: PT Serif, Sans Pro
	wp_enqueue_style('amp-theme-fonts',amp_fonts_url());
	// enqueue Site's (generated from sass) style sheet
	wp_enqueue_style( 'amp-style', get_stylesheet_uri() );

	// Enqueue scripts to handle navigation
	// TODO(@amedina): remove dependency with jQuery and custom JS
	wp_enqueue_script(
		'amp-navigation',
		get_template_directory_uri() . '/js/navigation.js',
		array('jquery'), // brings jquery version bundled with WP
		'20151215',
		true
	);
	// Need to define translatable strings for screen readers in functions.php,
	// and then pass the strings to the JavaScript file in the variable
	// called ampScreenReaderText.
	wp_localize_script(
		'amp-navigation',
		'ampScreenReaderText',
		array(
			'expand' => __( 'Expand child menu', 'amp' ),
			'collapse' => __( 'Collapse child menu', 'amp' )
		)
	);
	// Enqueue functions defined in my custom functions.js file
	wp_enqueue_script(
		'amp-functions', get_template_directory_uri() . '/js/functions.js',
		array('jquery'),
		'20170603',
		true // loads in the footer
	);


	wp_enqueue_script( 'amp-skip-link-focus-fix', get_template_directory_uri() . '/js/skip-link-focus-fix.js', array(), '20151215', true );

	if ( is_singular() && comments_open() && get_option( 'thread_comments' ) ) {
		wp_enqueue_script( 'comment-reply' );
	}
}
add_action( 'wp_enqueue_scripts', 'amp_scripts' );

/**
 * Implement the Custom Header feature.
 */
require get_template_directory() . '/inc/custom-header.php';

/**
 * Custom template tags for this theme.
 */
require get_template_directory() . '/inc/template-tags.php';

/**
 * Custom functions that act independently of the theme templates.
 */
require get_template_directory() . '/inc/extras.php';

/**
 * Customizer additions.
 */
require get_template_directory() . '/inc/customizer.php';

/**
 * Load Jetpack compatibility file.
 */
require get_template_directory() . '/inc/jetpack.php';