<?php
/**
 * Virtual File System: Mime
 *
 * $Id$
 *
 * @author gERD Schaufelberger <gerd@php-tools.net>
 * @license PHP License
 * @package WB
 * @subpackage vfs
 */

WBClass::load('WBLog'
            , 'WBVFS'
            , 'WBVFS_File');

/**
 * Virtual File System: Mime
 *
 *
 *
 * @version 0.3.0
 * @package WB
 * @subpackage vfs
 */
abstract class WBVFS_Mime extends WBStdClass
{
    /**
     * list of mime types that my convert to this one
     * @var array
     */
    protected $convertable = array();

    /**
     * file name
     * @var string
     */
    protected $file  =   null;

    /**
     * virtual file
     * @var WBVFS_File
     */
    protected $vfile;

    /**
     * file information
     * @var array
     */
    protected $info =   array();

    /**
     * logger
     * @var WBLog
     */
    protected $log;

    /**
     * major mime type
     * @var string
     */
    protected $mimeMajor = '';

    /**
     * minor mime type
     * @var string
     */
    protected $mimeMinor = '';

    /**
     * ask for special minor mime type
     * @var string
     */
    protected $requestedMimeMinor = WBVFS::MIME_PLAIN;

    /**
     * file name extension
     * @var string
     */
    protected $extension = 'bin';

    /**
     * Whether file view may be incremented
     * @var bool
     */
    protected $incrementable = false;

    /**
     * constructor
     *
     * Configure file utiltiy object
     *
     * @param array $parameter
     */
    final public function __construct($parameter = array())
    {
        $this->log          =   WBLog::start(__CLASS__);
        $this->mimeMajor    =   strtolower(substr(get_class($this), (strlen(__CLASS__) + 1)));
        $this->init();
    }

    /**
     * 2nd constructor
     *
     */
    protected function init()
    {
    }

    /**
     * tell mime handler wich file to work with
     *
     * @param string $file
     * @param string $minor
     * @param string $name
     */
    final public function setFile($file, $minor, $name = '')
    {
        $this->file         =   $file;
        $this->mimeMinor    =   $minor;

        $this->onSetFile($name);
    }

    /**
     * inform when file was set
     *
     * @param string $name
     */
    protected function onSetFile($name = '')
    {
    }

    /**
     * set viretual file
     *
     * This function return whether it is possible to convert the file
     * to target mime type
     *
     * @param WBVFS_File $file
     * @return bool
     */
    final public function setVirtualFile(WBVFS_File $file)
    {
        $this->vfile        =   $file;
        $this->mimeMajor    =   $this->vfile->getMime(WBVFS_File::MIME_MAJOR);
        $this->mimeMinor    =   $this->vfile->getMime(WBVFS_File::MIME_MINOR);

        $this->onSetVirtualFile();
        $myMime =   strtolower(substr(get_class($this), strlen('WBVFS_Mime_')));

        if ($this->mimeMajor == $myMime) {
            return true;
        }

        if (!in_array($this->mimeMajor, $this->convertable)) {
            return false;
        }

        return true;
    }

    /**
     * inform when virtual file was set
     *
     */
    protected function onSetVirtualFile()
    {
    }

    /**
     * get viretual file
     *
     * @return WBVFS_File $file
     */
    final public function getVirtualFile()
    {
        return $this->vfile;
    }

    /**
     * execute command
     *
     * Each mime type may implement commands like unpack for ziped archives
     * or rotating for images
     *
     * @param string $cmd
     * @param array $arg
     */
    public function execute($cmd, $arg = array())
    {
        $log    =   array(
                'file'      =>  $this->vfile->getId(),
                'mime'      =>  $this->mimeMajor,
                'cmd'       =>  $cmd,
                'status'    =>  'notimplemented'
            );
        $this->log->err($log);
    }

    /**
     * get file name of requested file
     *
     * This is just a template method that forward call
     *
     * @see doGetRequestedFile()
     * @throws WBException_Argument
     * @param WBRequest $req
     * @param WBResponse $res
     * @param bool $redirect whether to redirect
     * @param string|null requested minor mime type
     * @return string
     */
    final public function getRequestedFile($req, $res, &$redirect, $minor = null)
    {
        $this->req  =   $req;
        $this->res  =   $res;
        $this->incrementable    =   true;
        if ($minor) {
            $this->requestedMimeMinor   =   $minor;
        }
        return $this->doGetRequestedFile($redirect);
    }

    /**
     * get file name of requested file
     *
     * @param bool $redirect whether to redirect
     * @return string
     */
    protected function doGetRequestedFile(&$redirect)
    {
        $this->mimeMajor    =   $this->vfile->getMime(WBVFS_File::MIME_MAJOR);
        $this->mimeMinor    =   $this->vfile->getMime(WBVFS_File::MIME_MINOR);
        return $this->vfile->getPath();
    }

    /**
     * Increment View?
     *
     * Tell whether file view should be incremented
     * @return bool
     */
    public function isIncrementable()
    {
        return $this->incrementable;
    }

    /**
     * fetch dynamic mime type
     *
     * @param int $type
     * @return string
     */
    final public function getMime($type = WBVFS_File::MIME_MAJOR)
    {
        if ($type == WBVFS_File::MIME_MAJOR) {
            return $this->mimeMajor;
        }
        if ($type == WBVFS_File::MIME_MINOR) {
            return $this->mimeMinor;
        }
        if ($type == (WBVFS_File::MIME_MAJOR | WBVFS_File::MIME_MINOR) ) {
            return $this->mimeMajor . '/' . $this->mimeMinor;
        }

        return null;
    }

    /**
     * get file extension
     *
     * Return Windows friendly file extension
     *
     * @return string
     */
    public function getExtension()
    {
        return $this->extension;
    }

    /**
     * gather information about this file
     *
     * Get with and height of images or videos, exif headers,
     * or content of ZIP-archive.
     *
     * @return array
     */
    public function getInfo()
    {
        return $this->info;
    }

    /**
     * import file
     *
     * Do whatever is required to import file,
     * of course, this may replace the original file
     */
    public function import()
    {
    }

    /**
     * tell whether file needs to be queued
     *
     * If a file is put in queue, it waits for asynchronious processing.
     * This is very importand for tasks that just take too long to to
     * right on import
     *
     * @todo actually, there is no queued processing.- everythin gets done on demand.
     * @return bool
     */
    public function queue()
    {
        return false;
    }

    /**
     * make cache folder
     *
     * @return string
     */
    protected function mkCacheDir()
    {
        $file       =   WBClass::create('WBFile');
        /** @var $file WBFile */

        $varDir     =   realpath(WBParam::get('wb/dir/base') . '/var');
        $myMime     =   strtolower(substr(get_class($this), strlen('WBVFS_Mime_')));
        $cacheDir   =   'var/cache' . substr($this->vfile->getPath(), strlen($varDir)) . '/' . $myMime;

        $file->mkdir($cacheDir);
        return $file->realpath();
    }
}