<?php

class WP_Site_Icon {
	private static $instance = null;

	/**
	 * The minimum size of the site icon.
	 *
	 * @since 4.3.0
	 *
	 * @var int
	 */
	public $min_size  = 512;

	/**
	 *
	 * @since 4.3.0
	 *
	 * @var array
	 */
	public $site_icon_sizes = array(
		/**
		 * Square, medium sized tiles for IE11+.
		 *
		 * @link https://msdn.microsoft.com/library/dn455106(v=vs.85).aspx
		 */
		270,

		/**
		 * App icons up to iPhone 6 Plus.
		 *
		 * @link https://developer.apple.com/library/prerelease/ios/documentation/UserExperience/Conceptual/MobileHIG/IconMatrix.html
		 */
		180,

		// Our regular Favicon.
		32,
	);

	static function get_instance() {
		if ( is_null( self::$instance ) ) {
			self::$instance = new WP_Site_Icon;
		}
		return self::$instance;
	}

	/**
	 * Add Site Icon sizes to the array of image sizes on demand.
	 *
	 * @since 4.3.0
	 *
	 * @param array $sizes
	 * @return array
	 */
	public function intermediate_image_sizes( $sizes = array() ) {
		/** This filter is documented in wp-admin/includes/site-icon.php */
		$this->site_icon_sizes = apply_filters( 'site_icon_image_sizes', $this->site_icon_sizes );
		foreach ( $this->site_icon_sizes as $size ) {
			$sizes[] = 'site_icon-' . $size;
		}

		return $sizes;
	}

	/**
	 * Add additional sizes to be made when creating the site_icon images.
	 *
	 * @since 4.3.0
	 *
	 * @param array $sizes
	 * @return array
	 */
	public function additional_sizes( $sizes = array() ) {
		$only_crop_sizes = array();

		/**
		 * Filter the different dimensions that a site icon is saved in.
		 *
		 * @since 4.3.0
		 *
		 * @param array $site_icon_sizes Sizes available for the Site Icon.
		 */
		$this->site_icon_sizes = apply_filters( 'site_icon_image_sizes', $this->site_icon_sizes );

		// Use a natural sort of numbers.
		natsort( $this->site_icon_sizes );
		$this->site_icon_sizes = array_reverse( $this->site_icon_sizes );

		// ensure that we only resize the image into
		foreach ( $sizes as $name => $size_array ) {
			if ( $size_array['crop'] ) {
				$only_crop_sizes[ $name ] = $size_array;
			}
		}

		foreach ( $this->site_icon_sizes as $size ) {
			if ( $size < $this->min_size ) {
				$only_crop_sizes[ 'site_icon-' . $size ] = array(
					'width ' => $size,
					'height' => $size,
					'crop'   => true,
				);
			}
		}

		return $only_crop_sizes;
	}


}