--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/service/piNode/devices.py	Sun May 31 00:56:55 2015 -0700
@@ -0,0 +1,122 @@
+from __future__ import division
+import pigpio
+import time
+from rdflib import Namespace, RDF, URIRef, Literal
+
+ROOM = Namespace('http://projects.bigasterisk.com/room/')
+
+class DeviceType(object):
+    deviceType = None
+    @classmethod
+    def findInstances(cls, graph, board, pi):
+        """
+        return any number of instances of this class for all the separately
+        controlled devices on the board. Two LEDS makes two instances,
+        but two sensors on the same onewire bus makes only one device
+        (which yields more statements).
+        """
+        for row in graph.query("""SELECT ?dev ?pinNumber WHERE {
+                                    ?board :hasPin ?pin .
+                                    ?pin :pinNumber ?pinNumber;
+                                         :connectedTo ?dev .
+                                    ?dev a ?thisType .
+                                  } ORDER BY ?dev""",
+                               initBindings=dict(board=board,
+                                                 thisType=cls.deviceType),
+                               initNs={'': ROOM}):
+            yield cls(graph, row.dev, pi, int(row.pinNumber))
+
+    def __init__(self, graph, uri, pi, pinNumber):
+        self.graph, self.uri, self.pi = graph, uri, pi
+        self.pinNumber = pinNumber
+
+    def description(self):
+        return {
+            'uri': self.uri,
+            'className': self.__class__.__name__,
+            'pinNumber': self.pinNumber,
+            'outputPatterns': self.outputPatterns(),
+            'watchPrefixes': self.watchPrefixes(),
+            'outputWidgets': self.outputWidgets(),
+        }
+
+    def watchPrefixes(self):
+        """
+        subj,pred pairs of the statements that might be returned from
+        readFromPoll, so the dashboard knows what it should
+        watch. This should be eliminated, as the dashboard should just
+        always watch the whole tree of statements starting self.uri
+        """
+        return []
+
+    def poll(self):
+        return [] # statements
+    
+    def outputPatterns(self):
+        """
+        Triple patterns, using None as a wildcard, that should be routed
+        to sendOutput
+        """
+        return []
+
+    def outputWidgets(self):
+        """
+        structs to make output widgets on the dashboard. ~1 of these per
+        handler you have in sendOutput
+        """
+        return []
+        
+    def sendOutput(self, statements):
+        """
+        If we got statements that match this class's outputPatterns, this
+        will be called with the statements that matched. 
+
+        Todo: it would be fine to read back confirmations or
+        whatever. Just need a way to collect them into graph statements.
+        """
+        raise NotImplementedError
+        
+_knownTypes = set()
+def register(deviceType):
+    _knownTypes.add(deviceType)
+    return deviceType
+
+@register
+class MotionSensorInput(DeviceType):
+    deviceType = ROOM['MotionSensor']
+
+    def setup(self):
+        self.pi.set_mode(17, pigpio.INPUT)
+        self.pi.set_pull_up_down(17, pigpio.PUD_DOWN)
+
+    def poll(self):
+        motion = self.pi.read(17)
+        
+        return [
+            (self.uri, ROOM['sees'],
+             ROOM['motion'] if motion else ROOM['noMotion']),
+            self.recentMotionStatement(motion),
+        ]
+
+    def recentMotionStatement(self, motion):
+        if not hasattr(self, 'lastMotionTime'):
+            self.lastMotionTime = 0
+        now = time.time()
+        if motion:
+            self.lastMotionTime = now
+        recentMotion = now - self.lastMotionTime < 60 * 10
+        return (self.uri, ROOM['seesRecently'],
+                ROOM['motion'] if recentMotion else ROOM['noMotion'])        
+    
+    def watchPrefixes(self):
+        return [
+            (self.uri, ROOM['sees']),
+            (self.uri, ROOM['seesRecently']),
+        ]
+
+def makeDevices(graph, board, pi):
+    out = []
+    for dt in sorted(_knownTypes, key=lambda cls: cls.__name__):
+        out.extend(dt.findInstances(graph, board, pi))
+    return out
+