<?php
/**
 * Client for the Listbright API. The store's key is created on first use.
 *
 * @package Listbright
 */

defined( 'ABSPATH' ) || exit;

class Listbright_API {

	const KEY_OPTION = 'listbright_api_key';

	/**
	 * Calls the API and returns the decoded reply or a WP_Error.
	 *
	 * @param string     $method  GET or POST.
	 * @param string     $path    Endpoint, like /scan.
	 * @param array|null $body    JSON body.
	 * @param int        $timeout Seconds.
	 * @return array|WP_Error
	 */
	public static function request( $method, $path, $body = null, $timeout = 60 ) {
		$key = self::key();
		if ( is_wp_error( $key ) ) {
			return $key;
		}
		return self::send( $method, $path, $body, $timeout, $key );
	}

	/**
	 * The saved key, registering the store first if there is none.
	 *
	 * @return string|WP_Error
	 */
	public static function key() {
		$key = get_option( self::KEY_OPTION );
		if ( $key ) {
			return $key;
		}
		$reply = self::send( 'POST', '/register', array( 'site' => home_url() ), 30 );
		if ( is_wp_error( $reply ) ) {
			return $reply;
		}
		update_option( self::KEY_OPTION, $reply['key'], false );
		return $reply['key'];
	}

	private static function send( $method, $path, $body, $timeout, $key = null ) {
		$args = array(
			'method'  => $method,
			'timeout' => $timeout,
			'headers' => array( 'Content-Type' => 'application/json' ),
		);
		if ( $key ) {
			$args['headers']['Authorization'] = 'Bearer ' . $key;
		}
		if ( null !== $body ) {
			$args['body'] = wp_json_encode( $body );
		}
		$res = wp_remote_request( untrailingslashit( LISTBRIGHT_API ) . $path, $args );
		if ( is_wp_error( $res ) ) {
			return new WP_Error( 'listbright_unreachable', __( 'Could not reach the Listbright service. Try again in a minute.', 'listbright' ) );
		}
		$code = wp_remote_retrieve_response_code( $res );
		$data = json_decode( wp_remote_retrieve_body( $res ), true );
		if ( 401 === $code && $key ) {
			// The key was removed on the server; start over with a new one.
			delete_option( self::KEY_OPTION );
		}
		if ( $code >= 400 || ! is_array( $data ) ) {
			$message = is_array( $data ) && ! empty( $data['error'] ) ? $data['error'] : __( 'The Listbright service had a problem.', 'listbright' );
			return new WP_Error( 'listbright_api', $message, array( 'status' => $code ) );
		}
		return $data;
	}
}