<?php

class RscDtgs_Cache
{
  /**
   * @var RscDtgs_Cache_Interface
   */
  protected $adapter;

  /**
   * @var string
   */
  protected $prefix;

  /**
   * @var int
   */
  protected $ttl;

  /**
   * Constructor
   * @param RscDtgs_Cache_Interface $adapter The caching adapter
   */
  public function __construct(RscDtgs_Cache_Interface $adapter)
  {
    $this->adapter = $adapter;
  }

  /**
   * Adds data to the cache
   * @param string $key The key for the cached data
   * @param mixed $data The data for the cache
   * @return bool TRUE on success, FALSE otherwise
   */
  public function set($key, $data)
  {
    return $this->adapter->set($this->prefix . $key, $data, $this->ttl);
  }

  /**
   * Get the cached data by the specified key
   * @param string $key The key for the cached data
   * @return mixed|null The cached data of NULL on failure or if the cached data is not fresh
   */
  public function get($key)
  {
    return $this->adapter->get($this->prefix . $key);
  }

  /**
   * Deletes the cached data for the specified key
   * @param string $key The key for the cached data
   * @return bool TRUE on success, FALSE otherwise
   */
  public function delete($key)
  {
    return $this->adapter->delete($this->prefix . $key);
  }

  /**
   * Clears the cache
   * @return bool TRUE on success, FALSE otherwise
   */
  public function clear()
  {
    return $this->adapter->clear();
  }

  /**
   * Sets the prefix for keys
   * @param string $prefix
   * @return RscDtgs_Cache
   */
  public function setPrefix($prefix)
  {
    $this->prefix = $prefix;
    return $this;
  }

  /**
   * Returns the prefix for keys
   * @return string
   */
  public function getPrefix()
  {
    return $this->prefix;
  }

  /**
   * Sets the time to life for cached data
   * @param int $ttl
   * @return RscDtgs_Cache
   */
  public function setTtl($ttl)
  {
    $this->ttl = (int) $ttl;
    return $this;
  }

  /**
   * Returns the time to life for cached data
   * @return int
   */
  public function getTtl()
  {
    return $this->ttl;
  }
}
