functions.php

<?php
/**
 * Twenty Seventeen functions and definitions
 *
 * @link https://developer.wordpress.org/themes/basics/theme-functions/
 *
 * @package WordPress
 * @subpackage Twenty_Seventeen
 * @since 1.0
 */

if ( ! function_exists( 'twentyseventeen_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 twentyseventeen_setup() {
	/*
	 * Make theme available for translation.
	 * Translations can be filed at WordPress.org. See: https://translate.wordpress.org/projects/wp-themes/twentyseventeen
	 * If you're building a theme based on Twenty Seventeen, use a find and replace
	 * to change 'twentyseventeen' to the name of your theme in all the template files.
	 */
	load_theme_textdomain( 'twentyseventeen' );

	// 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/
	 */
	add_theme_support( 'post-thumbnails' );

	add_image_size( 'twentyseventeen-featured-image', 2000, 1200, true );

	add_image_size( 'twentyseventeen-thumbnail-avatar', 100, 100, true );

	// This theme uses wp_nav_menu() in two locations.
	register_nav_menus( array(
		'top'    => __( 'Top', 'twentyseventeen' ),
		'social' => __( 'Social Links Menu', 'twentyseventeen' ),
	) );

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

	/*
	 * Enable support for Post Formats.
	 *
	 * See: https://codex.wordpress.org/Post_Formats
	 */
	add_theme_support( 'post-formats', array(
		'aside',
		'image',
		'video',
		'quote',
		'link',
		'gallery',
		'audio',
	) );

	// Add theme support for Custom Logo.
	add_theme_support( 'custom-logo', array(
		'width'       => 1000,
		'height'      => 1000,
		'flex-width'  => true,
		'flex-height' => true,
	) );
}
endif;
add_action( 'after_setup_theme', 'twentyseventeen_setup' );


/**
 * 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 twentyseventeen_content_width() {
	$GLOBALS['content_width'] = apply_filters( 'twentyseventeen_content_width', 700 );
}
add_action( 'after_setup_theme', 'twentyseventeen_content_width', 0 );


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

	/**
	 * Translators: If there are characters in your language that are not
	 * supported by Libre Frankin, translate this to 'off'. Do not translate
	 * into your own language.
	 */
	$libre_franklin = _x( 'on', 'libre_franklin font: on or off', 'twentyseventeen' );

	if ( 'off' !== $libre_franklin ) {
		$font_families = array();

		$font_families[] = 'Libre Franklin:300,300i,400,400i,600,600i,800,800i';

		$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 );
}

/**
 * Register widget area.
 *
 * @link https://developer.wordpress.org/themes/functionality/sidebars/#registering-a-sidebar
 */
function twentyseventeen_widgets_init() {
	register_sidebar( array(
		'name'          => __( 'Sidebar', 'twentyseventeen' ),
		'id'            => 'sidebar-1',
		'description'   => '',
		'before_widget' => '<section id="%1$s" class="widget %2$s">',
		'after_widget'  => '</section>',
		'before_title'  => '<h2 class="widget-title">',
		'after_title'   => '</h2>',
	) );

	register_sidebar( array(
		'name'          => __( 'Footer 1', 'twentyseventeen' ),
		'id'            => 'sidebar-2',
		'description'   => '',
		'before_widget' => '<section id="%1$s" class="widget %2$s">',
		'after_widget'  => '</section>',
		'before_title'  => '<h2 class="widget-title">',
		'after_title'   => '</h2>',
	) );

	register_sidebar( array(
		'name'          => __( 'Footer 2', 'twentyseventeen' ),
		'id'            => 'sidebar-3',
		'description'   => '',
		'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', 'twentyseventeen_widgets_init' );


/**
 * Output Custom Logo.
 */
function twentyseventeen_the_custom_logo() {
	if ( function_exists( 'the_custom_logo' ) ) {
		the_custom_logo();
	}
}


if ( ! function_exists( 'twentyseventeen_excerpt_continue_reading' ) ) {
/**
 * Replaces the excerpt "more" text by a link
 */
function twentyseventeen_excerpt_continue_reading() {
	return ' &hellip; <p class="link-more"><a href="' . esc_url( get_permalink() ) . '">' . sprintf( __( 'Continue reading', 'twentyseventeen' ), the_title( '<span class="screen-reader-text">"', '"</span>', false ) ) . '</a></p>';
}
}
add_filter( 'excerpt_more', 'twentyseventeen_excerpt_continue_reading' );


/**
 * Handles JavaScript detection.
 *
 * Adds a `js` class to the root `<html>` element when JavaScript is detected.
 *
 * @since Twenty Seventeen 1.0
 */
function twentyseventeen_javascript_detection() {
	echo "<script>(function(html){html.className = html.className.replace(/\bno-js\b/,'js')})(document.documentElement);</script>\n";
}
add_action( 'wp_head', 'twentyseventeen_javascript_detection', 0 );

/**
 * Enqueue scripts and styles.
 */
function twentyseventeen_scripts() {
	// Add custom fonts, used in the main stylesheet.
	wp_enqueue_style( 'twentyseventeen-fonts', twentyseventeen_fonts_url(), array(), null );

	// Add Genericons, used in the main stylesheet.
	wp_enqueue_style( 'genericons', get_template_directory_uri() . '/assets/genericons/genericons.css', array(), '3.4.1' );

	// Theme stylesheet.
	wp_enqueue_style( 'twentyseventeen-style', get_stylesheet_uri() );

	// Load the Internet Explorer 8 specific stylesheet.
	wp_enqueue_style( 'twentyseventeen-ie8', get_template_directory_uri() . '/assets/css/ie8.css', array( 'twentyseventeen-style' ), '20160928' );
	wp_style_add_data( 'twentyseventeen-ie8', 'conditional', 'lt IE 9' );

	// Load the html5 shiv.
	wp_enqueue_script( 'html5', get_template_directory_uri() . '/assets/js/html5.js', array(), '3.7.3' );
	wp_script_add_data( 'html5', 'conditional', 'lt IE 9' );

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

	wp_enqueue_script( 'twentyseventeen-navigation', get_template_directory_uri() . '/assets/js/navigation.js', array(), '20151215', true );

	wp_localize_script( 'twentyseventeen-navigation', 'twentyseventeenScreenReaderText', array(
		'expand'   => __( 'Expand child menu', 'twentyseventeen' ),
		'collapse' => __( 'Collapse child menu', 'twentyseventeen' ),
	) );

	wp_enqueue_script( 'twentyseventeen-global', get_template_directory_uri() . '/assets/js/global.js', array( 'jquery' ), '20151215', true );

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

	// Scroll effects (only loaded on front page).
	if ( twentyseventeen_is_frontpage() || ( is_home() && is_front_page() ) ) {
		wp_enqueue_script( 'jquery-scrollto', get_template_directory_uri() . '/assets/js/jquery.scrollTo.js', array( 'jquery' ), '20151030', true );
	}

}
add_action( 'wp_enqueue_scripts', 'twentyseventeen_scripts' );


/**
 * Add custom image sizes attribute to enhance responsive image functionality
 * for content images
 *
 * @since Twenty Seventeen 1.0
 *
 * @param string $sizes A source size value for use in a 'sizes' attribute.
 * @param array  $size  Image size. Accepts an array of width and height
 *                      values in pixels (in that order).
 * @return string A source size value for use in a content image 'sizes' attribute.
 */
function twentyseventeen_content_image_sizes_attr( $sizes, $size ) {
	$width = $size[0];

	740 <= $width && $sizes = '(max-width: 706px) 89vw, (max-width: 767px) 82vw, 740px';

	if ( is_active_sidebar( 'sidebar-1' ) || is_archive() || is_search() || is_home() || is_page() ) {
		if ( ! ( is_page() && 'one-column' === get_theme_mod( 'page_options' ) ) ) {
			767 <= $width && $sizes = '(max-width: 767px) 89vw, (max-width: 1000px) 54vw, (max-width: 1071px) 543px, 580px';
		}
	}

	return $sizes;
}
add_filter( 'wp_calculate_image_sizes', 'twentyseventeen_content_image_sizes_attr', 10 , 2 );

/**
 * Add custom image sizes attribute to enhance responsive image functionality
 * for post thumbnails
 *
 * @since Twenty Seventeen 1.0
 *
 * @param array $attr Attributes for the image markup.
 * @param int   $attachment Image attachment ID.
 * @param array $size Registered image size or flat array of height and width dimensions.
 * @return string A source size value for use in a post thumbnail 'sizes' attribute.
 */
function twentyseventeen_post_thumbnail_sizes_attr( $attr, $attachment, $size ) {
	if ( is_archive() || is_search() || is_home() ) {
		$attr['sizes'] = '(max-width: 767px) 89vw, (max-width: 1000px) 54vw, (max-width: 1071px) 543px, 580px';
	} else {
		$attr['sizes'] = '100vw';
	}
	return $attr;
}
add_filter( 'wp_get_attachment_image_attributes', 'twentyseventeen_post_thumbnail_sizes_attr', 10 , 3 );


/**
 * 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';