Matter Thermostat: Add 'off' to thermostatMode by default only if switch is not supported

drivers/SmartThings/matter-thermostat/src/test/test_matter_room_ac.lua

@@ -481,4 +481,88 @@ test.register_message_test(
   }
 )
 
+local ControlSequenceOfOperation = clusters.Thermostat.attributes.ControlSequenceOfOperation
+test.register_message_test(
+  "Room AC control sequence reports should generate correct messages",
+  {
+    {
+      channel = "matter",
+      direction = "receive",
+      message = {
+        mock_device.id,
+        ControlSequenceOfOperation:build_test_report_data(mock_device, 1, ControlSequenceOfOperation.COOLING_AND_HEATING_WITH_REHEAT)
+      }
+    },
+    {
+      channel = "capability",
+      direction = "send",
+      message = mock_device:generate_test_message("main", capabilities.thermostatMode.supportedThermostatModes({"cool", "heat"}, {visibility={displayed=false}}))
+    },
+    {
+      channel = "matter",
+      direction = "receive",
+      message = {
+        mock_device.id,
+        ControlSequenceOfOperation:build_test_report_data(mock_device, 1, ControlSequenceOfOperation.HEATING_WITH_REHEAT)
+      }
+    },
+    {
+      channel = "capability",
+      direction = "send",
+      message = mock_device:generate_test_message("main", capabilities.thermostatMode.supportedThermostatModes({"heat"}, {visibility={displayed=false}}))
+    },
+    {
+      channel = "matter",
+      direction = "receive",
+      message = {
+        mock_device.id,
+        ControlSequenceOfOperation:build_test_report_data(mock_device, 1, ControlSequenceOfOperation.COOLING_WITH_REHEAT)
+      }
+    },
+    {
+      channel = "capability",
+      direction = "send",
+      message = mock_device:generate_test_message("main", capabilities.thermostatMode.supportedThermostatModes({"cool"}, {visibility={displayed=false}}))
+    },
+  }
+)
+
+test.register_message_test(
+  "Additional mode reports should extend the supported modes",
+  {
+    {
+      channel = "matter",
+      direction = "receive",
+      message = {
+        mock_device.id,
+        clusters.Thermostat.server.attributes.ControlSequenceOfOperation:build_test_report_data(mock_device, 1, 5)
+      }
+    },
+    {
+      channel = "capability",
+      direction = "send",
+      message = mock_device:generate_test_message("main", capabilities.thermostatMode.supportedThermostatModes({"cool", "heat"}, {visibility={displayed=false}}))
+    },
+		{
+      channel = "matter",
+      direction = "receive",
+      message = {
+        mock_device.id,
+        clusters.Thermostat.server.attributes.SystemMode:build_test_report_data(mock_device, 1, 5)
+      }
+    },
+    {
+      channel = "capability",
+      direction = "send",
+      message = mock_device:generate_test_message("main", capabilities.thermostatMode.supportedThermostatModes({"cool", "heat", "emergency heat"}, {visibility={displayed=false}}))
+    },
+		{
+      channel = "capability",
+      direction = "send",
+      message = mock_device:generate_test_message("main", capabilities.thermostatMode.thermostatMode.emergency_heat())
+    }
+  }
+)
+
+
 test.run_registered_tests()

drivers/SmartThings/matter-thermostat/src/thermostat_handlers/attribute_handlers.lua

@@ -84,9 +84,13 @@ end
 function AttributeHandlers.control_sequence_of_operation_handler(driver, device, ib, response)
   -- The ControlSequenceOfOperation attribute only directly specifies what can't be operated by the operating environment, not what can.
   -- However, we assert here that a Cooling enum value implies that SystemMode supports cooling, and the same for a Heating enum.
-  -- We also assert that Off is supported, though per spec this is optional.
+  -- We also assert that Off is supported if the switch capability is not supported, though per spec this is optional.
   if device:get_field(fields.OPTIONAL_THERMOSTAT_MODES_SEEN) == nil then
-    device:set_field(fields.OPTIONAL_THERMOSTAT_MODES_SEEN, {capabilities.thermostatMode.thermostatMode.off.NAME}, {persist=true})
+    if device:supports_capability(capabilities.switch) == false then
+      device:set_field(fields.OPTIONAL_THERMOSTAT_MODES_SEEN, {capabilities.thermostatMode.thermostatMode.off.NAME}, {persist=true})
+    else
+      device:set_field(fields.OPTIONAL_THERMOSTAT_MODES_SEEN, {}, {persist=true})
+    end
   end
   local supported_modes = st_utils.deep_copy(device:get_field(fields.OPTIONAL_THERMOSTAT_MODES_SEEN))
   local disallowed_mode_operations = {}