<?php
class Enigma_SteckerBoard implements Enigma_Encryptor_Interface
{
    protected $_steckers=array();

    public function clearAllSteckers()
    {
        $this->_steckers=array();
    }

    public function setStecker($from,$to)
    {
        if(!(preg_match('/^[A-Z]$/',$from) && preg_match('/^[A-Z]$/',$to))) {
            throw new Exception("Invalid stecker pair $from-$to");
        }

        if(isset($_this->_steckers[$from])) {
            throw new Exception("Stecker socket $from already used");
        }

        if(isset($_this->_steckers[$to])) {
            throw new Exception("Stecker socket $to already used");
        }

        $this->_steckers[$from]=$to;
        $this->_steckers[$to]=$from;
    }

    public function setSteckers($assocArray)
    {
        $this->clearAllSteckers();

        foreach($assocArray as $from=>$to)
        {
            $this->setStecker($from,$to);
        }
    }

    public function getOutputCharacterForInputCharacter ($inputCharacter)
    {
        if(isset($this->_steckers[$inputCharacter])) {
            $char=$this->_steckers[$inputCharacter];
        } else {
            $char=$inputCharacter;
        }

        return $char;
    }

}