<?php
/**
 * Same-origin REST proxy for the block editor: the browser calls these with
 * its wp-admin cookie, the WordPress server calls Coverground with the
 * connection token. No CORS anywhere, and the token never reaches a browser.
 */

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

function coverground_register_rest_routes() {
	register_rest_route(
		'coverground/v1',
		'/routes',
		array(
			'methods'             => WP_REST_Server::READABLE,
			'permission_callback' => 'coverground_rest_permission',
			'callback'            => function () {
				return rest_ensure_response( coverground_rest_result( coverground_get_routes() ) );
			},
		)
	);

	register_rest_route(
		'coverground/v1',
		'/routes/(?P<company>[a-z0-9-]+)/(?P<slug>[a-z0-9-]+)/card',
		array(
			'methods'             => WP_REST_Server::READABLE,
			'permission_callback' => 'coverground_rest_permission',
			'callback'            => function ( WP_REST_Request $request ) {
				// The company segment keeps refs readable, but the token already
				// pins the subscriber — the slug alone addresses the route.
				$body = coverground_api_get( '/routes/' . $request['slug'] . '/card' );

				// The cover photo is copied into the media library (attachment
				// id + local URL), so the published card serves its own image
				// and keeps working when Coverground is unreachable. There is no
				// hotlink fallback: without a copy the card gets no image, and
				// media_status tells the editor why (copied | none |
				// no_permission | failed).
				if ( ! is_wp_error( $body ) ) {
					$body['media']        = null;
					$body['media_status'] = 'none';
					if ( ! empty( $body['thumbnail_url'] ) ) {
						if ( ! current_user_can( 'upload_files' ) ) {
							$body['media_status'] = 'no_permission';
						} else {
							$body['media']        = coverground_import_thumbnail( $body );
							$body['media_status'] = $body['media'] ? 'copied' : 'failed';
						}
					}
				}

				return rest_ensure_response( coverground_rest_result( $body ) );
			},
		)
	);

	register_rest_route(
		'coverground/v1',
		'/status',
		array(
			'methods'             => WP_REST_Server::READABLE,
			'permission_callback' => 'coverground_rest_permission',
			'callback'            => function () {
				return rest_ensure_response( coverground_rest_result( coverground_api_get( '/status' ) ) );
			},
		)
	);
}
add_action( 'rest_api_init', 'coverground_register_rest_routes' );

function coverground_rest_permission(): bool {
	return current_user_can( 'edit_posts' );
}

/** WP_Error passes through as-is — its stable code drives the editor copy. */
function coverground_rest_result( $result ) {
	return $result;
}

/**
 * Copy a card's cover photo into the media library and return what the block
 * needs to reference it, or null when the copy failed. Identical bytes
 * for the same route reuse the existing attachment (dedupe by ref + content
 * hash); a changed photo gets a fresh attachment, so an older card's image
 * keeps rendering untouched. The route's alt rides along onto the attachment
 * — empty stays empty, the deliberate decorative signal.
 *
 * @param array $payload The card payload from Coverground.
 * @return array{id: int, url: string}|null
 */
function coverground_import_thumbnail( array $payload ): ?array {
	if ( empty( $payload['thumbnail_url'] ) || empty( $payload['ref'] ) || ! current_user_can( 'upload_files' ) ) {
		return null;
	}

	require_once ABSPATH . 'wp-admin/includes/file.php';
	require_once ABSPATH . 'wp-admin/includes/media.php';
	require_once ABSPATH . 'wp-admin/includes/image.php';

	$tmp = download_url( $payload['thumbnail_url'], 15 );
	if ( is_wp_error( $tmp ) ) {
		return null;
	}

	$hash     = md5_file( $tmp );
	$existing = get_posts(
		array(
			'post_type'      => 'attachment',
			'post_status'    => 'inherit',
			'posts_per_page' => 1,
			'fields'         => 'ids',
			'meta_query'     => array( // phpcs:ignore WordPress.DB.SlowDBQuery.slow_db_query_meta_query -- one narrow dedupe lookup per card load.
				array( 'key' => '_coverground_ref', 'value' => $payload['ref'] ),
				array( 'key' => '_coverground_hash', 'value' => $hash ),
			),
		)
	);

	if ( $existing ) {
		wp_delete_file( $tmp );
		$id = (int) $existing[0];
	} else {
		$file = array(
			'name'     => sanitize_file_name( str_replace( '/', '-', $payload['ref'] ) . '.jpg' ),
			'tmp_name' => $tmp,
		);
		$id   = media_handle_sideload( $file, 0, (string) ( $payload['title'] ?? '' ) );
		if ( is_wp_error( $id ) ) {
			wp_delete_file( $tmp );
			return null;
		}
		update_post_meta( $id, '_coverground_ref', $payload['ref'] );
		update_post_meta( $id, '_coverground_hash', $hash );
	}

	// Also on reuse: the owner may have changed the alt on Coverground without
	// touching the photo bytes — the library copy's alt must follow.
	update_post_meta( $id, '_wp_attachment_image_alt', (string) ( $payload['thumbnail_alt'] ?? '' ) );

	$url = wp_get_attachment_url( $id );

	return $url ? array( 'id' => $id, 'url' => $url ) : null;
}