1 files changed, 33 insertions, 0 deletions
diff --git a/glucometerutils/support/construct_extras.py b/glucometerutils/support/construct_extras.py
new file mode 100644
index 0000000..cb42105
--- /dev/null
+++ b/glucometerutils/support/construct_extras.py
@@ -0,0 +1,33 @@
+# -*- coding: utf-8 -*-
+"""Extra classes for Construct."""
+
+__author__ = 'Diego Elio Pettenò'
+__email__ = 'flameeyes@flameeyes.eu'
+__copyright__ = 'Copyright © 2018, Diego Elio Pettenò'
+__license__ = 'MIT'
+
+import datetime
+
+import construct
+
+class Timestamp(construct.Adapter):
+    """Adapter for converting datetime object into timestamps.
+
+    Take two parameters: the subcon object to output the resulting timestamp as,
+    and an optional epoch offset to the UNIX Epoch.
+
+    """
+    __slots__ = ["epoch"]
+
+    def __init__(self, subcon, epoch=0):
+        super(Timestamp, self).__init__(subcon)
+        self.epoch = epoch
+
+    def _encode(self, obj, context):
+        assert isinstance(obj, datetime.datetime)
+        epoch_date = datetime.datetime.utcfromtimestamp(self.epoch)
+        delta = obj - epoch_date
+        return int(delta.total_seconds())
+
+    def _decode(self, obj, context):
+        return datetime.datetime.utcfromtimestamp(obj + self.epoch)