From 0fae036609cb7537304b01e8c7d13784413264bb Mon Sep 17 00:00:00 2001
From: Luca <Luca@hackerspace-bamberg.de>
Date: Thu, 5 Sep 2024 21:45:14 +0200
Subject: [PATCH] feat: server disconnect handling

---
 mqtt.lua | 23 +++++++++++++++++++----
 1 file changed, 19 insertions(+), 4 deletions(-)

diff --git a/mqtt.lua b/mqtt.lua
index 6a895ce..f16bd7c 100644
--- a/mqtt.lua
+++ b/mqtt.lua
@@ -131,12 +131,27 @@ function MqttClient:handle ()
 
         self.is_connecting = false
         self.is_connected = true
-    elseif ptype == 0x40 then -- PUBACK
+    elseif ptype & 0xF0 == 0x40 then -- PUBACK
         -- TODO
-    elseif ptype == 0xD0 then -- PINGRESP
-        -- TODO
-    elseif ptype == 0xE0 then -- DISCONNECT
+    elseif ptype & 0xF0 == 0xD0 then -- PINGRESP
         -- TODO
+    elseif ptype & 0xF0 == 0xE0 then -- DISCONNECT
+        if ptype ~= 0xE0 then
+            self:disconnect(0x81)
+            return "malformed packet"
+        end
+
+        self.is_connecting = false
+        self.is_connected = false
+
+        if length > 0 then
+            reason, _ = string.unpack("B", data)
+            if reason ~= 0 then
+                return "disconnect with error"
+            end
+        end
+
+        return "disconnect"
     end
 
     return nil