sea: make sure status is error when reading main value failed

+ cosmetic changes using status codes

Change-Id: Ice49a6d5494d2e2cba76d138f11dffeba9aa349d

frappy_psi/sea.py

@@ -39,6 +39,7 @@ from os.path import expanduser, join, exists
 from frappy.client import ProxyClient
 from frappy.datatypes import ArrayOf, BoolType, \
     EnumType, FloatRange, IntRange, StringType
+from frappy.core import IDLE, BUSY, ERROR
 from frappy.errors import ConfigError, HardwareError, secop_error, CommunicationFailedError
 from frappy.lib import generalConfig, mkthread
 from frappy.lib.asynconn import AsynConn, ConnectionClosed
@@ -641,6 +642,10 @@ class SeaModule(Module):
         if upd:
             upd(value, timestamp, readerror)
             return
+        self.announceUpdate(parameter, value, readerror, timestamp)
+        # self._update(module, parameter, value, timestamp, readerror)
+
+    def _update(self, module, parameter, value, timestamp, readerror):
         try:
             pobj = self.parameters[parameter]
         except KeyError:
@@ -667,20 +672,36 @@ class SeaModule(Module):
 
 
 class SeaReadable(SeaModule, Readable):
+    _readerror = None
+    _status = IDLE, ''
+
+    def update_value(self, value, timestamp, readerror):
+        # make sure status is always ERROR when reading value fails
+        self._readerror = readerror
+        if readerror:
+            self.read_status()
+            self.announceUpdate('value', value, readerror, timestamp)
+            # self._update(self.name, 'value', value, timestamp, readerror)
+        else:  # order is important
+            self.value = value
+            self.read_status()
 
     def update_status(self, value, timestamp, readerror):
         if readerror:
             value = repr(readerror)
         if value == '':
-            self.status = (self.Status.IDLE, '')
+            self._status = IDLE, ''
         else:
-            self.status = (self.Status.ERROR, value)
+            self._status = ERROR, value
+        self.read_status()
 
     def read_status(self):
-        return self.status
+        if self._readerror:
+            return ERROR, repr(self._readerror)
+        return self._status
 
 
-class SeaWritable(SeaModule, Writable):
+class SeaWritable(SeaReadable, Writable):
     def read_value(self):
         return self.target
 
@@ -690,20 +711,13 @@ class SeaWritable(SeaModule, Writable):
             self.value = value
 
 
-class SeaDrivable(SeaModule, Drivable):
-    _sea_status = ''
+class SeaDrivable(SeaReadable, Drivable):
     _is_running = 0
 
     def earlyInit(self):
         super().earlyInit()
         self._run_event = threading.Event()
 
-    def read_status(self):
-        return self.status
-
-    # def read_target(self):
-    #    return self.target
-
     def write_target(self, value):
         self._run_event.clear()
         self.io.query(f'run {self.sea_object} {value}')
@@ -711,25 +725,20 @@ class SeaDrivable(SeaModule, Drivable):
             self.log.warn('target changed but is_running stays 0')
         return value
 
-    def update_status(self, value, timestamp, readerror):
-        if not readerror:
-            self._sea_status = value
-            self.updateStatus()
-
     def update_is_running(self, value, timestamp, readerror):
         if not readerror:
             self._is_running = value
-            self.updateStatus()
+            self.read_status()
             if value:
                 self._run_event.set()
 
-    def updateStatus(self):
-        if self._sea_status:
-            self.status = (self.Status.ERROR, self._sea_status)
-        elif self._is_running:
-            self.status = (self.Status.BUSY, 'driving')
-        else:
-            self.status = (self.Status.IDLE, '')
+    def read_status(self):
+        status = super().read_status()
+        if self._is_running:
+            if status[0] >= ERROR:
+                return ERROR, 'BUSY + ' + status[1]
+            return BUSY, 'driving'
+        return status
 
     def updateTarget(self, module, parameter, value, timestamp, readerror):
         if value is not None: