<?php
class Tool {
	private $key = "rtwertwerwg47878"; //可以自定義
	public function setKey($key = NULL) {
		$this->key = (! $key) ? $this->key : $key;
	}

	public function encrypt($input, $is_id = FALSE) { // 資料加密
		static $_map = array ();
		if ($is_id)
			$input = base_convert ( $input, 10, 36 );
		$hashkey = md5 ( $input . $this->key );
		if (isset ( $_map [$hashkey] ))
			return $_map [$hashkey];
		$size = mcrypt_get_block_size ( MCRYPT_3DES, 'ecb' );
		$input = $this->pkcs5_pad ( $input, $size );
		$key = str_pad ( $this->key, 24, '0' );
		$td = mcrypt_module_open ( MCRYPT_3DES, '', 'ecb', '' );
		$iv = @mcrypt_create_iv ( mcrypt_enc_get_iv_size ( $td ), MCRYPT_RAND );
		@mcrypt_generic_init ( $td, $key, $iv );
		$data = mcrypt_generic ( $td, $input );
		mcrypt_generic_deinit ( $td );
		mcrypt_module_close ( $td );
        $tmp = '';
		if ($is_id) {
			$len = strlen ( $data );
			for($i = 0; $i < $len; $i ++)
				$tmp = $tmp . str_pad ( dechex ( ord ( $data {$i} ) ), 2, 0, STR_PAD_LEFT );
			$_map [$hashkey] = $tmp;
			return $tmp;
		}
		$_map [$hashkey] = $tmp;
		$data = base64_encode ( $data );
		return $data;
	}
	public function decrypt($encrypted, $is_id = FALSE) { // 資料解密
		static $_map = array ();
		if ($is_id) {
			$len = strlen ( $encrypted );
			$tmp = '';
			for($i = 0; $i < $len; $i = $i + 2)
				$tmp = $tmp . chr ( hexdec ( $encrypted {$i} . $encrypted {$i + 1} ) );
			$encrypted = $tmp;
		} else
			$encrypted = base64_decode ( $encrypted );
		$hashkey = md5 ( $encrypted . $this->key );
		if (isset ( $map [$hashkey] ))
			return $_map [$hashkey];
		$key = str_pad ( $this->key, 24, '0' );
		$td = mcrypt_module_open ( MCRYPT_3DES, '', 'ecb', '' );
		$iv = @mcrypt_create_iv ( mcrypt_enc_get_iv_size ( $td ), MCRYPT_RAND );
		$ks = mcrypt_enc_get_key_size ( $td );
		@mcrypt_generic_init ( $td, $key, $iv );
		$decrypted = mdecrypt_generic ( $td, $encrypted );
		mcrypt_generic_deinit ( $td );
		mcrypt_module_close ( $td );
		$y = $this->pkcs5_unpad ( $decrypted );
		if ($is_id)
			$y = base_convert ( $y, 36, 10 );
		$_map [$hashkey] = $y;
		return $y;
	}

	private function pkcs5_pad($text, $blocksize) {
		$pad = $blocksize - (strlen ( $text ) % $blocksize);
		return $text . str_repeat ( chr ( $pad ), $pad );
	}
	private function pkcs5_unpad($text) {
		$pad = ord ( $text {strlen ( $text ) - 1} );
		if ($pad > strlen ( $text )) {
			return false;
		}
		if (strspn ( $text, chr ( $pad ), strlen ( $text ) - $pad ) != $pad) {
			return false;
		}
		return substr ( $text, 0, - 1 * $pad );
	}

	public function encrypt_v1($val) {
		static $_map = array ();
		$hashkey = md5 ( $val );
		if (isset ( $_map [$hashkey] ))
			return $_map [$hashkey];
		$val += 60512868;
		$_map [$hashkey] = base_convert ( $val, 10, 36 );
		return $_map [$hashkey];
	}
	public function decrypt_v1($val) {
		static $_map = array ();
		$hashkey = md5 ( $val );
		if (isset ( $_map [$hashkey] ))
			return $_map [$hashkey];
		$id = base_convert ( $val, 36, 10 );
		$_map [$hashkey] = $id - 60512868;
		return $_map [$hashkey];
	}
	public function encrypt_v2($val) {
		static $_map = array ();
		$e = "0123456789abcdefghijklmnopqrstuvwxyz";
		$e_1 = "abcdefghijklmnopqrstuvwxyz";
		$hashkey = md5 ( $e . $e_1 . $val );
		if (isset ( $_map [$hashkey] ))
			return $_map [$hashkey];
		$str = $val;
		$str = strval ( $str );
		$len = strlen ( $str );
		$f_len = $len * 3;
		$ps = '';
		while ( strlen ( $ps ) <= $f_len ) {
			$ps .= strtolower ( md5 ( rand ( 0, 99999999 ) ) );
		}
		$ps = substr ( $ps, 0, $f_len );
		$en_3 = substr ( $ps, - 1 * $len - (strlen ( strval ( $len ) )) + 1 );
		$en_3_int = array ();
		for($i = 0; $i < strlen ( $en_3 ); $i ++) {
			$tmp_id_e = strpos ( $e, $str {$i} ) + strpos ( $e, $en_3 {$i} );
			array_push ( $en_3_int, $e {$tmp_id_e % strlen ( $e )} );
		}
		$ps_array = str_split ( $ps );
		for($i = 0; $i <= count ( $ps_array ); $i ++) {
			if ($i % 2 == 1 && isset ( $en_3_int [$i / 2] )) {
				$ps_array [$i] = $en_3_int [$i / 2];
			}
		}
		$m_str = implode ( $ps_array, '' );
		$pm_len = count ( base_convert ( $len, 10, 26 ) );
		$m_str = $m_str . substr ( md5 ( $m_str ), 0, $pm_len );
		$_map [$hashkey] = $m_str;
		return $m_str;
	}
	public function decrypt_v2($val) {
		$e = "0123456789abcdefghijklmnopqrstuvwxyz";
		$e_1 = "abcdefghijklmnopqrstuvwxyz";
		$str = $val;
		static $_map = array ();
		$hashkey = md5 ( $e . $e_1 . $val );
		if (isset ( $_map [$hashkey] ))
			return $_map [$hashkey];
		$erclen = strlen ( $str ) - floor ( strlen ( $str ) / 3 ) * 3;
		if ($str && substr ( md5 ( substr ( $str, 0, - 1 * $erclen ) ), 0, $erclen ) == substr ( $str, - 1 * $erclen )) {
			$t_len = floor ( strlen ( $str ) / 3 );
			$en_1 = substr ( $str, - 1 * $t_len - ceil ( $t_len / strlen ( $e_1 ) ), - 1 * ceil ( $t_len / strlen ( $e_1 ) ) );
			$s_str_array = array ();
			for($i = 0; $i <= $t_len * 2; $i ++) {
				if ($i % 2 == 1 && $i / 2 < $t_len) {
					$id_s = $str {$i};
					@$id_i = $e {((strpos ( $e, $id_s ) + strlen ( $e )) - strpos ( $e, $en_1 {$i / 2} )) % strlen ( $e )};
					array_push ( $s_str_array, $id_i );
				}
			}
			$s_str = implode ( $s_str_array, '' );
		} else
			$s_str = null;
		$_map [$hashkey] = $s_str;
		return $s_str;
	}
	public function encrypt_v3($val) {
		static $_map = array ();
		$hashkey = md5 ( $val );
		if (isset ( $_map [$hashkey] ))
			return $_map [$hashkey];
		$str = $val;
		$str = base64_encode ( gzcompress ( $str ) );
		$fix = substr ( $str, - 4 );
		$str = substr ( $str, 0, - 4 );
		$a = substr_count ( $fix, "=" );
		if ($a > 0)
			$str = substr ( substr ( $str, - 1 * $a ) . $str, 0, - 1 * $a );
		$strarr = str_split ( $str, strlen ( $str ) / 4 );
        $tmpstr = '';
		for($i = 0; $i < strlen ( $strarr [0] ); $i ++) {
			$tmpstr .= $strarr [0] {$i} . $strarr [1] {$i} . $strarr [2] {$i} . $strarr [3] {$i};
		}
		$tmpstr .= $fix;
		$_map [$hashkey] = $tmpstr;
		return $tmpstr;
	}
	public function decrypt_v3($val) {
		static $_map = array ();
		$hashkey = md5 ( $val );
		if (isset ( $_map [$hashkey] ))
			return $_map [$hashkey];
		$str = $val;
		$fix = substr ( $str, - 4 );
		$str = substr ( $str, 0, - 4 );
		$a = substr_count ( $fix, "=" );
        $tmp = array();
		for($i = 0; $i < strlen ( $str ); $i ++) {
           @$tmp [$i % 4] .= $str[$i];
		}
		$str = implode ( "", $tmp );
		if ($a > 0)
			$str = substr ( $str . substr ( $str, 0, $a ), $a );
		$str .= $fix;
		$_map [$hashkey] = gzuncompress ( base64_decode ( $str ) );
		return $_map [$hashkey];
	}
	public function encrypt_v4($id) {
		static $_map = array ();
		$hashkey = md5 ( $id );
		if (isset ( $_map [$hashkey] ))
			return $_map [$hashkey];
		$s1 = ($id + 201341) * 7;
		$l = strlen ( $s1 );
		$lb = intval ( $l / 2 );
		$lc = $l - $lb;
		$a = substr ( $s1, 0, $lb );
		// echo $a."\n";
		$b = substr ( $s1, - 1 * ($lc) );
		// echo $b."\n";
		$tmpstr = '';
		for($i = 0; $i < $lb; $i ++) {
			if ($i % 2 == 0) {
				$tmpstr .= $a {intval ( $i / 2 )} . $b {($lc - 1 - intval ( $i / 2 ))};
			} else {
				$tmpstr .= $b {intval ( $i / 2 )} . $a {($lb - intval ( $i / 2 ) - 1)};
			}
		}
		if ($l % 2 == 1)
			$tmpstr .= $b {intval ( ($lc - 1) / 2 )};
		$_map [$hashkey] = $tmpstr;
		return $tmpstr;
	}
	public function decrypt_v4($str) {
		static $_map = array();
		$hashkey = md5($str);
		if(isset($_map[$hashkey]))
			return $_map[$hashkey];
		$l = strlen ( $str );
		$tmpstr = array ();
		$flag = 1;
		$c = 0;
		for($i = 0; $i < $l; $i ++) {
			if ($i !== 0 && $i % 2 == 0){
				$flag = - $flag;
				if($flag==1)
					$c++;
			}
			if ($i == $l - 1) {
				for($j = 0; $j <= $l; $j ++)
					if(!isset($tmpstr[$j])){
						$tmpstr[$j]=$str[$i];
						break;
					}
			} else {
				if ($i % 2 == 0) {
					if ($flag == 1) {
						$tmpstr [intval ( $i / 2 )-$c] = $str [$i];
						//echo "1:$flag:$c:".(intval($i/2)-$c)."\n";
					} else {
						$tmpstr [intval ( $l / 2 ) +$c] = $str [$i];
						//echo "2:$flag:$c:".(intval ( $l / 2 ) +$c)."\n";
					}
				} else {
					if ($flag == 1) {
						$tmpstr [$l- intval ( ($i-$c*2)/ 2 ) -1] = $str [$i];
						//echo "3:$flag:$c:".($l - intval($i/ 2 ) -$c-1)."\n";
					} else {
						$tmpstr [intval ( $l / 2 ) - 1 - $c] = $str [$i];
						//echo "4:$flag:$c:".(intval ( $l / 2 ) - 1 - $c)."\n";
					}
				}
			}
			
		}
		ksort($tmpstr);
		$str = implode("",$tmpstr);
		$str = $str/7-201341;
		if(is_float($str))
			$str = null;
		$_map[$hashkey] = $str;
		return $str;
		//print_r($tmpstr);
	}

}
$a = new Tool();
$str = "890osds";
echo $c =$a->encrypt($str);
echo "<br>";
echo $a->decrypt($c );
echo "<br>";
echo $c =$a->encrypt_v1($str);
echo "<br>";
echo $a->decrypt_v1($c );
echo "<br>";
echo $c =$a->encrypt_v2($str);
echo "<br>";
echo $a->decrypt_v2($c );
echo "<br>";
echo $c =$a->encrypt_v3($str);
echo "<br>";
echo $a->decrypt_v3($c );
echo "<br>";
echo $c =$a->encrypt_v4($str);
echo "<br>";
echo $a->decrypt_v4($c );
echo "<br>";