<?php
//import from https://github.com/maysrp/t2magnet
//magnet($file) => magnet


function magnet($file){
    if(is_file($file)){
        $info=file_get_contents($file);
        $desc = BDecode($info);
        $info = $desc['info'];
        $b_tr=BEncode($info);
        $hash = sha1($b_tr);//ADD 
        $uri="magnet:?xt=urn:btih:".$hash;
        return $uri;
    }
}
//BDecode
class BDecode {
    function numberdecode($wholefile, $offset) {
        // Funky handling of negative numbers and zero
        $negative = false;
        if ($wholefile[$offset] == '-') {
            $negative = true;
            $offset++;
        }
        if ($wholefile[$offset] == '0') {
            $offset++;
            if ($negative)
                return array(false);
            if ($wholefile[$offset] == ':' || $wholefile[$offset] == 'e')
                return array(0, ++$offset);
            return array(false);
        }
        $ret[0] = 0;
        for(;;) {
            if ($wholefile[$offset] >= '0' && $wholefile[$offset] <= '9') {
                $ret[0] *= 10;
                //Added 2005.02.21 - VisiGod
        //Changing the type of variable from integer to double to prevent a numeric overflow
                settype($ret[0],'double');
                //Added 2005.02.21 - VisiGod
                $ret[0] += ord($wholefile[$offset]) - ord('0');
                $offset++;
            }	else if ($wholefile[$offset] == 'e' || $wholefile[$offset] == ':') {
                // Tolerate : or e because this is a multiuse function
                $ret[1] = $offset+1;
                if ($negative) {
                    if ($ret[0] == 0)
                        return array(false);
                    $ret[0] = - $ret[0];
                }
                return $ret;
            } else return array(false);
        }
    }

    function decodeEntry($wholefile, $offset=0) {
        if ($wholefile[$offset] == 'd')
            return $this->decodeDict($wholefile, $offset);
        if ($wholefile[$offset] == 'l')
            return $this->decodelist($wholefile, $offset);
        if ($wholefile[$offset] == 'i')
            return $this->numberdecode($wholefile, ++$offset);
        // String value: decode number, then grab substring

        $info = $this->numberdecode($wholefile, $offset);
        if ($info[0] === false)
            return array(false);
        $ret[0] = substr($wholefile, $info[1], $info[0]);
        $ret[1] = $info[1]+strlen($ret[0]);
        return $ret;
    }

    function decodeList($wholefile, $offset) {
        if ($wholefile[$offset] != 'l')
            return array(false);
        $offset++;
        $ret = array();
        for ($i=0;;$i++) {
            if ($wholefile[$offset] == 'e')
                break;
            $value = $this->decodeEntry($wholefile, $offset);
            if ($value[0] === false)
                return array(false);
            $ret[$i] = $value[0];
            $offset = $value[1];
        }
        // The empty list is an empty array. Seems fine.
        return array(0=>$ret, 1=>++$offset);
    }

    // Tries to construct an array
    function decodeDict($wholefile, $offset=0) {
        if ($wholefile[$offset] == 'l')
            return $this->decodeList($wholefile, $offset);
        if ($wholefile[$offset] != 'd')
            return false;
        $ret=array();
        $offset++;
        for (;;) {
            if ($wholefile[$offset] == 'e')	{
                $offset++;
                break;
            }
            $left = $this->decodeEntry($wholefile, $offset);
            if (!$left[0])
                return false;
            $offset = $left[1];
            if ($wholefile[$offset] == 'd') {
                // Recurse
                $value = $this->decodedict($wholefile, $offset);
                if (!$value[0])
                    return false;
                $ret[addslashes($left[0])] = $value[0];
                $offset= $value[1];
                continue;
            }
            if ($wholefile[$offset] == 'l') {
                $value = $this->decodeList($wholefile, $offset);
                if (!$value[0] && is_bool($value[0]))
                    return false;
                $ret[addslashes($left[0])] = $value[0];
                $offset = $value[1];
                continue;
            }
            $value = $this->decodeEntry($wholefile, $offset);
            if ($value[0] === false)
                return false;
            $ret[addslashes($left[0])] = $value[0];
            $offset = $value[1];
        }
        return array(0=>(empty($ret)?true:$ret), 1=>$offset);
    }
}

function BDecode($wholefile) {
    $decoder = new BDecode;
    $return = $decoder->decodeEntry($wholefile);
    return $return[0];
}
//BEncode

class BEncode {
    // Dictionary keys must be sorted. foreach tends to iterate over the order
    // the array was made, so we make a new one in sorted order. <img src="http://www.cevin.me/wp-includes/images/smilies/icon_smile.gif" alt=":)" class="wp-smiley">
    function makeSorted($array) {
        // Shouldn't happen!
        if (empty($array))
            return $array;
        $i = 0;
        foreach($array as $key => $dummy)
            $keys[$i++] = stripslashes($key);
        sort($keys);
        for ($i=0; isset($keys[$i]); $i++)
            $return[addslashes($keys[$i])] = $array[addslashes($keys[$i])];
        return $return;
    }

    // Encodes strings, integers and empty dictionaries.
    // $unstrip is set to true when decoding dictionary keys
    function encodeEntry($entry, &$fd, $unstrip = false) {
        if (is_bool($entry)) {
            $fd .= 'de';
            return;
        }
        if (is_int($entry) || is_float($entry)) {
            $fd .= 'i'.$entry.'e';
            return;
        }
        if ($unstrip)
            $myentry = stripslashes($entry);
        else
            $myentry = $entry;
        $length = strlen($myentry);
        $fd .= $length.':'.$myentry;
    }

    // Encodes lists
    function encodeList($array, &$fd) {
        $fd .= 'l';
        // The empty list is defined as array();
        if (empty($array)) {
            $fd .= 'e';
            return;
        }
        for ($i = 0; isset($array[$i]); $i++)
            $this->decideEncode($array[$i], $fd);
        $fd .= 'e';
    }

    // Passes lists and dictionaries accordingly, and has encodeEntry handle
    // the strings and integers.
    function decideEncode($unknown, &$fd) {
        if (is_array($unknown)) {
            if (isset($unknown[0]) || empty($unknown))
                return $this->encodeList($unknown, $fd);
            else
                return $this->encodeDict($unknown, $fd);
        }
        $this->encodeEntry($unknown, $fd);
    }

    // Encodes dictionaries
    function encodeDict($array, &$fd) {
        $fd .= 'd';
        if (is_bool($array)) {
            $fd .= 'e';
            return;
        }
        // NEED TO SORT!
        $newarray = $this->makeSorted($array);
        foreach($newarray as $left => $right) {
            $this->encodeEntry($left, $fd, true);
            $this->decideEncode($right, $fd);
        }
        $fd .= 'e';
    }
}

function BEncode($array) {
    $string = '';
    $encoder = new BEncode;
    $encoder->decideEncode($array, $string);
    return $string;
}
//BEncode