<?php

namespace DeliciousBrains\WPMDB\Common\Http;

use DeliciousBrains\WPMDB\Common\Util\Util;

class Scramble {

	/**
	 * Scramble string.
	 *
	 * @param mixed $input String to be scrambled.
	 *
	 * @return mixed
	 */
	function scramble( $input ) {
		if ( empty( $input ) ) {
			return $input;
		}

		if ( ! \is_string( $input ) && ! \is_bool( $input ) ) {
			$input = json_encode( $input );
		}

		return 'WPMDB-SCRAMBLED' . str_replace( array( '/', '\\' ), array( '%#047%', '%#092%' ), str_rot13( $input ) );
	}

	/**
	 * Unscramble string.
	 *
	 * @param mixed $input      String to be unscrambled.
	 * @param bool  $doing_json Are we already processing some JSON?
	 *
	 * @return mixed
	 */
	function unscramble( $input, $doing_json = false ) {
		if (
			! empty( $input ) &&
			is_string( $input ) &&
			( false !== strpos( $input, 'WPMDB-SCRAMBLED' ) || $doing_json )
		) {
			// We know we have scrambled data, but was it JSON encoded afterwards?
			if ( Util::is_json( $input ) ) {
				$input = json_decode( $input, true );
				if ( is_array( $input ) ) {
					foreach ( $input as $key => $val ) {
						$input[ $key ] = $this->unscramble( $val, true );
					}
				} else {
					$input = $this->unscramble( $input, true );
				}

				// Re-encode just once when finished doing JSON.
				if ( ! $doing_json ) {
					$input = json_encode( $input );
				}
			} elseif ( 0 === strpos( $input, 'WPMDB-SCRAMBLED' ) ) {
				// If the string begins with WPMDB-SCRAMBED we can unscramble.
				// As the scrambled string could be multiple segments of scrambling (from stow) we remove indicators in one go.
				$input = str_replace( array( 'WPMDB-SCRAMBLED', '%#047%', '%#092%' ), array( '', '/', '\\' ), $input );
				$input = str_rot13( $input );
			} elseif ( false !== strpos( $input, 'WPMDB-SCRAMBLED' ) ) {
				// Starts with non-scrambled data (error), but with scrambled string following.
				$pos   = strpos( $input, 'WPMDB-SCRAMBLED' );
				$input = substr( $input, 0, $pos ) . $this->unscramble( substr( $input, $pos ), $doing_json );
			}
		}

		return $input;
	}
}