<?php

namespace FlexifyBlocks\DynamicContent;

use WP_Post;

/**
 * Resolve the Image block's supported dynamic image sources.
 *
 * The returned image data mirrors the editor resolver: url, alt, dimensions,
 * and srcset where WordPress can provide them.
 *
 * @package flexify-blocks
 */
if ( ! defined( 'ABSPATH' ) ) {
	exit;
}

final class DynamicImageResolver {

	/**
	 * @param array        $config Dynamic image settings.
	 * @param WP_Post|null $post   Post to resolve against.
	 * @return array Resolved image data, or an empty array.
	 */
	public static function resolve( array $config, $post ) {
		$type = isset( $config['type'] ) && is_string( $config['type'] ) ? $config['type'] : '';

		if ( 'post_featured_image' === $type ) {
			if ( $post instanceof WP_Post && self::can_read( $post ) ) {
				$image = self::featured_image( $post, $config );
				if ( $image ) {
					return $image;
				}
			}

			return self::fallback_image( $config );
		}

		if ( 'author_profile_image' === $type && $post instanceof WP_Post && self::can_read( $post ) ) {
			$author_id = (int) $post->post_author;
			if ( ! $author_id ) {
				return array();
			}

			$url = get_avatar_url( $author_id, array( 'size' => 96 ) );
			if ( ! $url ) {
				return array();
			}

			return array(
				'url'    => esc_url_raw( $url ),
				'alt'    => (string) get_the_author_meta( 'display_name', $author_id ),
				'source' => 'dynamic',
			);
		}

		return array();
	}

	/** Resolve the post's featured image at the configured size. */
	private static function featured_image( WP_Post $post, array $config ) {
		$attachment_id = (int) get_post_thumbnail_id( $post );
		if ( ! $attachment_id ) {
			return array();
		}

		$size  = isset( $config['imageSize'] ) && is_string( $config['imageSize'] )
			? sanitize_key( $config['imageSize'] )
			: 'large';
		$media = wp_get_attachment_image_src( $attachment_id, $size );
		if ( ! $media ) {
			$media = wp_get_attachment_image_src( $attachment_id, 'full' );
		}
		if ( ! $media ) {
			return array();
		}

		return array(
			'id'     => $attachment_id,
			'url'    => esc_url_raw( $media[0] ),
			'alt'    => (string) get_post_meta( $attachment_id, '_wp_attachment_image_alt', true ),
			'width'  => (int) $media[1],
			'height' => (int) $media[2],
			'srcset' => (string) wp_get_attachment_image_srcset( $attachment_id, $size ),
			'source' => 'dynamic',
		);
	}

	/** Use the manually selected fallback image when the post has no featured image. */
	private static function fallback_image( array $config ) {
		$fallback = isset( $config['fallbackImage'] ) && is_array( $config['fallbackImage'] )
			? $config['fallbackImage']
			: array();
		$size     = isset( $config['imageSize'] ) && is_string( $config['imageSize'] )
			? sanitize_key( $config['imageSize'] )
			: 'large';
		$sizes    = isset( $fallback['sizes'] ) && is_array( $fallback['sizes'] )
			? $fallback['sizes']
			: array();
		$selected = isset( $sizes[ $size ] ) && is_array( $sizes[ $size ] )
			? $sizes[ $size ]
			: array();
		$url      = $selected['url'] ?? $selected['source_url'] ?? $fallback['url'] ?? $fallback['source_url'] ?? '';

		if ( ! is_string( $url ) || '' === $url ) {
			return array();
		}

		return array(
			'id'     => isset( $fallback['id'] ) ? (int) $fallback['id'] : null,
			'url'    => esc_url_raw( $url ),
			'alt'    => (string) ( $fallback['alt'] ?? $fallback['alt_text'] ?? '' ),
			'width'  => isset( $selected['width'] ) ? (int) $selected['width'] : null,
			'height' => isset( $selected['height'] ) ? (int) $selected['height'] : null,
			'source' => 'fallback',
		);
	}

	/** Published posts, or posts the current user can read in the editor preview. */
	private static function can_read( WP_Post $post ) {
		return 'publish' === $post->post_status || current_user_can( 'read_post', $post->ID );
	}
}