<?php

namespace Illuminate\Cache;

use Illuminate\Contracts\Cache\Store;

class MemcachedStore extends TaggableStore implements Store
{
    /**
     * The Memcached instance.
     *
     * @var \Memcached
     */
    protected $memcached;

    /**
     * A string that should be prepended to keys.
     *
     * @var string
     */
    protected $prefix;

    /**
     * Create a new Memcached store.
     *
     * @param  \Memcached  $memcached
     * @param  string      $prefix
     * @return void
     */
    public function __construct($memcached, $prefix = '')
    {
        $this->setPrefix($prefix);
        $this->memcached = $memcached;
    }

    /**
     * Retrieve an item from the cache by key.
     *
     * @param  string  $key
     * @return mixed
     */
    public function get($key)
    {
        $value = $this->memcached->get($this->prefix.$key);

        if ($this->memcached->getResultCode() == 0) {
            return $value;
        }
    }

    /**
     * Store an item in the cache for a given number of minutes.
     *
     * @param  string  $key
     * @param  mixed   $value
     * @param  int     $minutes
     * @return void
     */
    public function put($key, $value, $minutes)
    {
        $this->memcached->set($this->prefix.$key, $value, $minutes * 60);
    }

    /**
     * Store an item in the cache if the key doesn't exist.
     *
     * @param  string  $key
     * @param  mixed   $value
     * @param  int     $minutes
     * @return bool
     */
    public function add($key, $value, $minutes)
    {
        return $this->memcached->add($this->prefix.$key, $value, $minutes * 60);
    }

    /**
     * Increment the value of an item in the cache.
     *
     * @param  string  $key
     * @param  mixed   $value
     * @return int|bool
     */
    public function increment($key, $value = 1)
    {
        return $this->memcached->increment($this->prefix.$key, $value);
    }

    /**
     * Decrement the value of an item in the cache.
     *
     * @param  string  $key
     * @param  mixed   $value
     * @return int|bool
     */
    public function decrement($key, $value = 1)
    {
        return $this->memcached->decrement($this->prefix.$key, $value);
    }

    /**
     * Store an item in the cache indefinitely.
     *
     * @param  string  $key
     * @param  mixed   $value
     * @return void
     */
    public function forever($key, $value)
    {
        $this->put($key, $value, 0);
    }

    /**
     * Remove an item from the cache.
     *
     * @param  string  $key
     * @return bool
     */
    public function forget($key)
    {
        return $this->memcached->delete($this->prefix.$key);
    }

    /**
     * Remove all items from the cache.
     *
     * @return void
     */
    public function flush()
    {
        $this->memcached->flush();
    }

    /**
     * Get the underlying Memcached connection.
     *
     * @return \Memcached
     */
    public function getMemcached()
    {
        return $this->memcached;
    }

    /**
     * Get the cache key prefix.
     *
     * @return string
     */
    public function getPrefix()
    {
        return $this->prefix;
    }

    /**
     * Set the cache key prefix.
     *
     * @param  string  $prefix
     * @return void
     */
    public function setPrefix($prefix)
    {
        $this->prefix = ! empty($prefix) ? $prefix.':' : '';
    }
}
