<?php
/**
 * Plugin Name: Ansico Embed URL
 * Description: A Gutenberg block to embed a URL with a social-media style preview card. Automatically fetches metadata and saves the image locally.
 * Version: 1.0.0
 * Author: Ansico
 * Text Domain: ansico-embed-url
 */

if ( ! defined( 'ABSPATH' ) ) {
    exit;
}

// Register the block and its assets
add_action( 'init', 'ansico_embed_url_register_block' );
function ansico_embed_url_register_block() {
    wp_register_script(
        'ansico-embed-url-script',
        plugins_url( 'ansico-embed-url.js', __FILE__ ),
        array( 'wp-blocks', 'wp-element', 'wp-editor', 'wp-components', 'wp-api-fetch' ),
        '1.0.0'
    );

    wp_register_style(
        'ansico-embed-url-style',
        plugins_url( 'ansico-embed-url.css', __FILE__ ),
        array(),
        '1.0.0'
    );

    register_block_type( 'ansico/embed-url', array(
        'editor_script' => 'ansico-embed-url-script',
        'editor_style'  => 'ansico-embed-url-style',
        'style'         => 'ansico-embed-url-style',
    ) );
}

// Register REST API Route
add_action( 'rest_api_init', function () {
    register_rest_route( 'ansico/v1', '/fetch-url', array(
        'methods'  => 'POST',
        'callback' => 'ansico_embed_url_fetch_metadata',
        'permission_callback' => function () {
            return current_user_can( 'edit_posts' );
        }
    ) );
} );

function ansico_embed_url_fetch_metadata( $request ) {
    $url = esc_url_raw( $request->get_param( 'url' ) );
    
    if ( empty( $url ) ) {
        return new WP_Error( 'missing_url', 'No URL provided', array( 'status' => 400 ) );
    }

    $response = wp_remote_get( $url );
    if ( is_wp_error( $response ) ) {
        return new WP_Error( 'fetch_failed', 'Could not fetch URL', array( 'status' => 500 ) );
    }

    $html = wp_remote_retrieve_body( $response );
    
    libxml_use_internal_errors(true);
    $doc = new DOMDocument();
    $doc->loadHTML( mb_convert_encoding( $html, 'HTML-ENTITIES', 'UTF-8' ) );
    libxml_clear_errors();

    $title = '';
    $image_url = '';
    $domain = parse_url( $url, PHP_URL_HOST );
    $domain = str_replace( 'www.', '', $domain );

    $tags = $doc->getElementsByTagName( 'meta' );
    foreach ( $tags as $tag ) {
        if ( $tag->getAttribute( 'property' ) === 'og:title' ) {
            $title = $tag->getAttribute( 'content' );
        }
        if ( $tag->getAttribute( 'property' ) === 'og:image' ) {
            $image_url = $tag->getAttribute( 'content' );
        }
    }

    if ( empty( $title ) ) {
        $nodes = $doc->getElementsByTagName( 'title' );
        if ( $nodes->length > 0 ) {
            $title = $nodes->item(0)->nodeValue;
        }
    }

    $local_image_url = '';
    if ( ! empty( $image_url ) ) {
        require_once( ABSPATH . 'wp-admin/includes/media.php' );
        require_once( ABSPATH . 'wp-admin/includes/file.php' );
        require_once( ABSPATH . 'wp-admin/includes/image.php' );

        $sideloaded = media_sideload_image( $image_url, 0, null, 'src' );
        
        if ( ! is_wp_error( $sideloaded ) ) {
            $local_image_url = $sideloaded;
        } else {
            $local_image_url = $image_url;
        }
    }

    return rest_ensure_response( array(
        'title'  => $title,
        'image'  => $local_image_url,
        'domain' => $domain,
    ) );
}
?>