<?php
defined( 'ABSPATH' ) || exit;

/** Thin client for the PeppolKit REST API. */
class PeppolKit_Api {
	const OPTION_KEY = 'peppolkit_api_key';

	public static function key() {
		return (string) get_option( self::OPTION_KEY, '' );
	}

	public static function connected() {
		return '' !== self::key();
	}

	/** Registers this site and stores the API key. */
	public static function connect( $email ) {
		$res = self::request( 'POST', '/connect', array( 'platform' => 'woocommerce', 'siteUrl' => home_url(), 'email' => $email ), false );
		if ( is_wp_error( $res ) ) {
			return $res;
		}
		update_option( self::OPTION_KEY, $res['apiKey'], false );
		return $res;
	}

	/**
	 * @return array|WP_Error Decoded JSON, or an error with the API's message.
	 */
	public static function request( $method, $path, $body = null, $auth = true ) {
		$headers = array( 'Accept' => 'application/json' );
		if ( $auth ) {
			if ( ! self::connected() ) {
				return new WP_Error( 'peppolkit_not_connected', __( 'PeppolKit is not connected yet.', 'peppolkit' ) );
			}
			$headers['Authorization'] = 'Bearer ' . self::key();
		}
		$args = array(
			'method'  => $method,
			'timeout' => 45,
			'headers' => $headers,
		);
		if ( null !== $body ) {
			$args['headers']['Content-Type'] = 'application/json';
			$args['body']                    = wp_json_encode( $body );
		}
		$res = wp_remote_request( PEPPOLKIT_API_URL . $path, $args );
		if ( is_wp_error( $res ) ) {
			return $res;
		}
		$code = wp_remote_retrieve_response_code( $res );
		$data = json_decode( wp_remote_retrieve_body( $res ), true );
		if ( $code >= 400 ) {
			$msg = is_array( $data ) ? ( isset( $data['errors'] ) ? implode( '; ', (array) $data['errors'] ) : ( $data['error'] ?? '' ) ) : '';
			return new WP_Error( 'peppolkit_http_' . $code, $msg ? $msg : sprintf( 'HTTP %d', $code ), $data );
		}
		return is_array( $data ) ? $data : array();
	}
}