# HG changeset patch
# User Paul Boddie <paul@boddie.org.uk>
# Date 1414358516 -3600
# Node ID 5b96860644e4017018103b574fd74c241d0957f3
# Parent  18ffda1dbfc10c6e6a2d822bee26089622c8457c
Fixed period overlapping and conflicting functions to work as promised.

diff -r 18ffda1dbfc1 -r 5b96860644e4 imiptools/period.py
--- a/imiptools/period.py	Sun Oct 26 19:44:25 2014 +0100
+++ b/imiptools/period.py	Sun Oct 26 22:21:56 2014 +0100
@@ -14,12 +14,13 @@
 
     conflicts = []
     for start, end in periods:
-        period = period_overlaps(freebusy, (start, end))
-        if period:
+        overlapping = period_overlaps(freebusy, (start, end), get_conflicts)
+        if overlapping:
             if get_conflicts:
-                conflicts.append(period)
+                conflicts += overlapping
             else:
                 return True
+
     if get_conflicts:
         return conflicts
     else:
@@ -37,21 +38,44 @@
         else:
             i += 1
 
-def period_overlaps(freebusy, period):
+def period_overlaps(freebusy, period, get_periods=False):
 
     """
-    Return from 'freebusy' any period overlapping with the given 'period', or
-    None if no overlap occurs.
+    Return whether any period in 'freebusy' overlaps with the given 'period',
+    returning a collection of overlapping periods if 'get_periods' is set to a
+    true value.
     """
 
     dtstart, dtend = period[:2]
-    i = bisect_left(freebusy, (dtstart, dtend, None))
-    return (
-        i < len(freebusy) and (dtend is None or freebusy[i][0] < dtend) and freebusy[i]
-        or
-        i > 0 and freebusy[i - 1][1] > dtstart and freebusy[i - 1]
-        or
-        None
-        )
+    found = bisect_left(freebusy, (dtstart, dtend, None))
+
+    overlapping = []
+
+    # Find earlier overlapping periods.
+
+    i = found
+
+    while i > 0 and freebusy[i - 1][1] > dtstart:
+        if get_periods:
+            overlapping.insert(0, freebusy[i - 1])
+        else:
+            return True
+        i -= 1
+
+    # Find later overlapping periods.
+
+    i = found
+
+    while i < len(freebusy) and (dtend is None or freebusy[i][0] < dtend):
+        if get_periods:
+            overlapping.append(freebusy[i])
+        else:
+            return True
+        i += 1
+
+    if get_periods:
+        return overlapping
+    else:
+        return False
 
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