From dba3b458ba34d787c5afae755da22ea9d542c7d5 Mon Sep 17 00:00:00 2001
From: Stefan Allius <stefan.allius@t-online.de>
Date: Thu, 2 May 2024 23:59:55 +0200
Subject: [PATCH] add Modbus support

---
 app/src/gen3/talent.py | 58 +++++++++++++++++++++++++++++++++++++++---
 1 file changed, 54 insertions(+), 4 deletions(-)

diff --git a/app/src/gen3/talent.py b/app/src/gen3/talent.py
index 46302ac..f983c79 100644
--- a/app/src/gen3/talent.py
+++ b/app/src/gen3/talent.py
@@ -3,12 +3,15 @@ import logging
 import time
 from datetime import datetime
 
+
 if __name__ == "app.src.gen3.talent":
     from app.src.messages import hex_dump_memory, Message
+    from app.src.modbus import Modbus
     from app.src.config import Config
     from app.src.gen3.infos_g3 import InfosG3
 else:  # pragma: no cover
     from messages import hex_dump_memory, Message
+    from modbus import Modbus
     from config import Config
     from gen3.infos_g3 import InfosG3
 
@@ -41,13 +44,18 @@ class Talent(Message):
         self.contact_name = b''
         self.contact_mail = b''
         self.db = InfosG3()
+        self.forward_modbus_rep = False
         self.switch = {
             0x00: self.msg_contact_info,
             0x13: self.msg_ota_update,
             0x22: self.msg_get_time,
             0x71: self.msg_collector_data,
+            # 0x76:
+            0x77: self.msg_modbus,
+            # 0x78:
             0x04: self.msg_inverter_data,
         }
+        self.mb = Modbus()
 
     '''
     Our puplic methods
@@ -115,6 +123,18 @@ class Talent(Message):
                         f' Ctl: {int(self.ctrl):#02x} Msg: {fnc.__name__!r}')
         return
 
+    async def send_modbus_cmd(self, func, addr, val) -> None:
+        self.forward_modbus_rep = False
+        self.__build_header(0x70, 0x77)
+        self._send_buffer += b'\x00\x01\xa3\x28'
+        modbus_msg = self.mb.build_msg(1, func, addr, val)
+        self._send_buffer += struct.pack('!B', len(modbus_msg))
+        self._send_buffer += modbus_msg
+        _len = self.__finish_send_msg()
+        hex_dump_memory(logging.INFO, 'Send Modbus Command:',
+                        self._send_buffer[self.send_msg_ofs:], _len)
+        await self.flush_send_msg()
+
     def _init_new_client_conn(self) -> bool:
         contact_name = self.contact_name
         contact_mail = self.contact_mail
@@ -190,17 +210,20 @@ class Talent(Message):
         self.header_valid = True
         return
 
-    def __build_header(self, ctrl) -> None:
+    def __build_header(self, ctrl, msg_id=None) -> None:
+        if not msg_id:
+            msg_id = self.msg_id
         self.send_msg_ofs = len(self._send_buffer)
         self._send_buffer += struct.pack(f'!l{len(self.id_str)+1}pBB',
-                                         0, self.id_str, ctrl, self.msg_id)
-        fnc = self.switch.get(self.msg_id, self.msg_unknown)
+                                         0, self.id_str, ctrl, msg_id)
+        fnc = self.switch.get(msg_id, self.msg_unknown)
         logger.info(self.__flow_str(self.server_side, 'tx') +
                     f' Ctl: {int(ctrl):#02x} Msg: {fnc.__name__!r}')
 
-    def __finish_send_msg(self) -> None:
+    def __finish_send_msg(self) -> int:
         _len = len(self._send_buffer) - self.send_msg_ofs
         struct.pack_into('!l', self._send_buffer, self.send_msg_ofs, _len-4)
+        return _len
 
     def __dispatch_msg(self) -> None:
         fnc = self.switch.get(self.msg_id, self.msg_unknown)
@@ -348,6 +371,33 @@ class Talent(Message):
             self.inc_counter('Unknown_Ctrl')
         self.forward(self._recv_buffer, self.header_len+self.data_len)
 
+    def parse_modbus_header(self):
+
+        msg_hdr_len = 5
+
+        result = struct.unpack_from('!lB', self._recv_buffer,
+                                    self.header_len + 4)
+        modbus_len = result[1]
+        logger.debug(f'Ref: {result[0]}')
+        logger.debug(f'Modbus Len: {modbus_len}')
+        # logger.info(f'time: {datetime.utcfromtimestamp(result[2]).strftime(
+        # "%Y-%m-%d %H:%M:%S")}')
+        return msg_hdr_len, modbus_len
+
+    def msg_modbus(self):
+        hdr_len, modbus_len = self.parse_modbus_header()
+
+        if self.ctrl.is_req():
+            self.forward_modbus_rep = True
+            self.inc_counter('Modbus_Command')
+        elif self.ctrl.is_ind():
+            if not self.forward_modbus_rep:
+                return
+        else:
+            logger.warning('Unknown Ctrl')
+            self.inc_counter('Unknown_Ctrl')
+        self.forward(self._recv_buffer, self.header_len+self.data_len)
+
     def msg_unknown(self):
         logger.warning(f"Unknow Msg: ID:{self.msg_id}")
         self.inc_counter('Unknown_Msg')