Update unpack

src/Protocol.php

@@ -3,7 +3,7 @@
  * This file is part of Simps
  *
  * @link     https://github.com/simps/mqtt
- * @contact  luffy <[email protected]>
+ * @contact  lufei <[email protected]>
  *
  * For the full copyright and license information,
  * please view the LICENSE file that was distributed with this source code
@@ -13,6 +13,12 @@
 
 namespace Simps\MQTT;
 
+use Simps\MQTT\Exception\MQTTException;
+use Simps\MQTT\Exception\MQTTLengthException;
+use Simps\MQTT\Packet\UnPack;
+use Throwable;
+use TypeError;
+
 class Protocol
 {
     public static function pack(array $array)
@@ -21,5 +27,81 @@ public static function pack(array $array)
 
     public static function unpack(string $data)
     {
+        try {
+            $type = static::getType($data);
+            $remaining = static::getRemaining($data);
+            switch ($type) {
+                case Types::CONNECT:
+                    $package = UnPack::connect($remaining);
+                    break;
+                case Types::CONNACK:
+                    $package = UnPack::connAck($remaining);
+                    break;
+                case Types::PUBLISH:
+                    $dup = ord($data[0]) >> 3 & 0x1;
+                    $qos = ord($data[0]) >> 1 & 0x3;
+                    $retain = ord($data[0]) & 0x1;
+                    $package = UnPack::publish($dup, $qos, $retain, $remaining);
+                    break;
+                case Types::PUBACK:
+                case Types::PUBREC:
+                case Types::PUBREL:
+                case Types::PUBCOMP:
+                case Types::UNSUBACK:
+                    $package = ['type' => $type, 'message_id' => unpack('n', $remaining)[1]];
+                    break;
+                case Types::PINGREQ:
+                case Types::PINGRESP:
+                case Types::DISCONNECT:
+                    $package = ['type' => $type];
+                    break;
+                case Types::SUBSCRIBE:
+                    $package = UnPack::subscribe($remaining);
+                    break;
+                case Types::SUBACK:
+                    $package = UnPack::subAck($remaining);
+                    break;
+                case Types::UNSUBSCRIBE:
+                    $package = UnPack::unSubscribe($remaining);
+                    break;
+                default:
+                    $package = [];
+            }
+        } catch (TypeError $e) {
+            throw new MQTTException($e->getMessage(), $e->getCode());
+        } catch (Throwable $e) {
+            throw new MQTTException($e->getMessage(), $e->getCode());
+        }
+
+        return $package;
+    }
+
+    public static function getType(string $data)
+    {
+        return ord($data[0]) >> 4;
+    }
+
+    public static function getRemainingLength(string $data, &$headBytes)
+    {
+        $headBytes = $multiplier = 1;
+        $value = 0;
+        do {
+            if (!isset($data[$headBytes])) {
+                throw new MQTTLengthException('Malformed Remaining Length');
+            }
+            $digit = ord($data[$headBytes]);
+            $value += ($digit & 127) * $multiplier;
+            $multiplier *= 128;
+            ++$headBytes;
+        } while (($digit & 128) != 0);
+
+        return $value;
+    }
+
+    public static function getRemaining(string $data)
+    {
+        $remainingLength = static::getRemainingLength($data, $headBytes);
+
+        return substr($data, $headBytes, $remainingLength);
     }
 }