<?php

class DataMapperManager
{
  private $db;
  private $mappers = array();

  public function __construct(Database $db)
  {
    $this->db = $db;
  }

  public function getMapper($name)
  {
    if (!isset($this->mappers[$name])) {
      $class = $name . 'Mapper';
      if (class_exists($class)) {
        $mapper = new $class($this);
        if (!($mapper instanceof DataMapper))
          throw new Exception('"' . $name . 'Mapper" должен быть наследником класса DataMapper');
        $this->mappers[$name] = $mapper;
      } else
        throw new Exception('Невозможно найти класс "' . $name . 'Mapper"');
    }
    return $this->mappers[$name];
  }
  
  public function getDatabase()
  {
    return $this->db;
  }
}