<?php
class Norm_MapperRegistry
{
    private static $_mappers = array();

    /**
     *
     * @param $model
     * @return Norm_MapperAbstract
     */
    public static function get($model)
    {
        if ($model instanceof Norm_DomainObject) {
            $class = get_class($model);
        } else {
            $class = (string) $model;
        }

        if (!self::_hasMapperForClass($class)) {
            throw new Norm_Exception('No mapper for type "' . $class . '" found.');
        }

        return self::$_mappers[$class];
    }

    public static function set(Norm_IMapper $mapper)
    {
        $class = $mapper->getDomainClass();

        if (self::_hasMapperForClass($class)) {
            throw new Norm_Exception('Mapper for class ' . $class . 'has already been registered.');
        }

        self::$_mappers[$class] = $mapper;
    }

    private static function _hasMapperForClass($class)
    {
        return isset(self::$_mappers[$class]);
    }
}