<?php

namespace Metadata\Cache;

use Metadata\ClassMetadata;

class FileCache implements CacheInterface

{

    private $dir;

    public function __construct($dir)

    {

        if (!is_dir($dir)) {

            throw new \InvalidArgumentException(sprintf('The directory "%s" does not exist.', $dir));

        }

        if (!is_writable($dir)) {

            throw new \InvalidArgumentException(sprintf('The directory "%s" is not writable.', $dir));

        }

        $this->dir = rtrim($dir, '\\/');

    }

    public function loadClassMetadataFromCache(\ReflectionClass $class)

    {

        $path = $this->dir.'/'.strtr($class->getName(), '\\', '-').'.cache.php';

        if (!file_exists($path)) {

            return null;

        }

        return include $path;

    }

    public function putClassMetadataInCache(ClassMetadata $metadata)

    {

        $path = $this->dir.'/'.strtr($metadata->name, '\\', '-').'.cache.php';

        file_put_contents($path, '<?php return unserialize('.var_export(serialize($metadata), true).');');

    }

    public function evictClassMetadataFromCache(\ReflectionClass $class)

    {

        $path = $this->dir.'/'.strtr($class->getName(), '\\', '-').'.cache.php';

        if (file_exists($path)) {

            unlink($path);

        }

    }

}