Facilitate Ethercalc cells specification

Rather than have to list every Ethercalc cell (and add comments
to every such cell to indicate room/time), describe the shape
of the ethercalc and automate retrieval of information.

Change-Id: I6939a1a7c5706d6f67b03b07ed11d9daf8c297c9

config.json.sample

@@ -1,10 +1,40 @@
 {
-"irc_nick": "NICK",
-"irc_pass": "PASS",
-"irc_server": "irc.freenode.net",
-"irc_port": 6667,
-"irc_channel": "#mychannel",
-"db_filename": "html/ptg.json",
-"ethercalc_url": "https://ethercalc.openstack.org/_/YOURDOC/cells",
-"ethercalc_cells": ["E9", "E10", "E11"]
+  "irc_nick": "NICK",
+  "irc_pass": "",
+  "irc_server": "irc.freenode.net",
+  "irc_port": 6667,
+  "irc_channel": "#CHANNEL",
+  "db_filename": "html/ptg.json",
+  "ethercalc_url": "https://ethercalc.openstack.org/_/MYDOC/cells",
+  "ethercalc_cells": {
+    "room_line": "8",
+    "time_column": "A",
+    "time_range": [ 9, 24 ],
+    "days": [
+      {
+        "B": ["14", "15", "16"],
+        "C": [],
+        "D": []
+      },
+      {
+        "E": ["14", "15", "16"],
+        "F": [],
+        "G": []
+      },
+      {
+        "H": ["14", "15", "16"],
+        "I": [],
+        "J": []
+      },
+      {
+        "K": ["14", "15", "16"],
+        "L": [],
+        "M": []
+      },
+      {
+        "N": [],
+        "O": []
+      }
+    ]
+  }
 }

ptgbot/ethercalc.py

@@ -14,6 +14,7 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
+import datetime
 import requests
 
 
@@ -21,15 +22,30 @@ class Ethercalc():
 
     def __init__(self, url, cells_spec):
         self.url = url
-        self.cells = cells_spec
+        self.room_line = cells_spec['room_line']
+        self.time_column = cells_spec['time_column']
+        time_range = range(cells_spec['time_range'][0],
+                           cells_spec['time_range'][1])
+        self.times = [str(i) for i in time_range]
+        self.days = cells_spec['days']
 
     def load(self):
         doc = requests.get(self.url).json()
         ret = []
-        for cell in self.cells:
-            if ('comment' in doc[cell] and
-               'datavalue' in doc[cell]):
-                msg = '%s: %s' % (doc[cell]['comment'],
-                                  doc[cell]['datavalue'])
-                ret.append(msg)
+        today = datetime.datetime.today().weekday()
+        if len(self.days) <= today:
+            return ret
+        for time in self.times:
+            for room, exclusions in self.days[today].items():
+                if time not in exclusions:
+                    datacell = room + time
+                    roomcell = room + self.room_line
+                    timecell = self.time_column + time
+                    if doc[datacell]['datavalue']:
+                        msg = '%s, %s: %s' % (
+                            doc[timecell]['datavalue'],
+                            doc[roomcell]['datavalue'],
+                            doc[datacell]['datavalue'],
+                        )
+                        ret.append(msg)
         return ret