<?php
/**
 * ImageObject nodes.
 *
 * @package ElevenRank
 * @since   1.0.0
 */

namespace ElevenRank\Modules\Schema;

defined( 'ABSPATH' ) || exit;

/**
 * Describes an image of the media library.
 *
 * @since 1.0.0
 */
final class Image_Node {

	/**
	 * The ImageObject of an attachment.
	 *
	 * @since 1.0.0
	 *
	 * @param int    $attachment_id Attachment id.
	 * @param string $node_id       `@id` of the node.
	 * @return array<string, mixed>|null Null when the attachment is not an image that has an address.
	 */
	public static function build( int $attachment_id, string $node_id ): ?array {
		if ( $attachment_id < 1 || ! wp_attachment_is_image( $attachment_id ) ) {
			return null;
		}

		$source = wp_get_attachment_image_src( $attachment_id, 'full' );

		if ( ! is_array( $source ) || '' === (string) $source[0] ) {
			return null;
		}

		$alt = trim( (string) get_post_meta( $attachment_id, '_wp_attachment_image_alt', true ) );

		return array(
			'@type'      => 'ImageObject',
			'@id'        => $node_id,
			'url'        => $source[0],
			'contentUrl' => $source[0],
			'width'      => (int) $source[1] > 0 ? (int) $source[1] : null,
			'height'     => (int) $source[2] > 0 ? (int) $source[2] : null,
			'caption'    => '' !== $alt ? wp_strip_all_tags( $alt ) : null,
		);
	}

	/**
	 * The address of an attachment's full-size image.
	 *
	 * @since 1.0.0
	 *
	 * @param int $attachment_id Attachment id.
	 * @return string Empty when there is none.
	 */
	public static function url( int $attachment_id ): string {
		if ( $attachment_id < 1 || ! wp_attachment_is_image( $attachment_id ) ) {
			return '';
		}

		$source = wp_get_attachment_image_src( $attachment_id, 'full' );

		return is_array( $source ) ? (string) $source[0] : '';
	}
}