kaiowa

diff --git a/kaiowa/reminder.py b/kaiowa/reminder.py
new file mode 100644
index 0000000000000000000000000000000000000000..81e828e7ecb549fad4792610abfd7d99873923a7
--- /dev/null
+++ b/kaiowa/reminder.py
@@ -0,0 +1,55 @@
+import json
+import asyncio
+
+from collections import namedtuple
+from datetime import datetime
+from parsedatetime import Calendar
+from pytz import timezone
+
+Reminder = namedtuple("Reminder", ["what", "when", "who"])
+UTC = timezone("UTC")
+local = timezone("Brazil/East")
+
+async def want_reminder(redis, reminders, msg, what=None, when=None):
+    if not what or not when:
+        return
+
+    cal = Calendar()
+    now = datetime.utcnow().replace(tzinfo=UTC).astimezone(local)
+    when, _ = cal.parseDT(datetimeString=when, sourceTime=now, tzinfo=local)
+
+    reminder = Reminder(what=what, who=msg.sender.name, when=when)
+    reminders.append(reminder)
+    save_reminders(redis, reminders)
+    await msg.reply(f"Ok, vou te lembrar em {when}")
+
+def encode_reminder(reminder):
+    return {
+        "what": reminder.what,
+        "when": reminder.when.timestamp(),
+        "who": reminder.who
+    }
+
+def save_reminders(redis, reminders):
+    redis.set("reminders", json.dumps([encode_reminder(r) for r in reminders]))
+
+def decode_reminder(obj):
+    obj["when"] = datetime.fromtimestamp(obj["when"], tz=local)
+    return Reminder(**obj)
+
+def load_reminders(redis):
+    reminders = redis.get("reminders")
+    if not reminders:
+        return []
+
+    return [decode_reminder(r) for r in json.loads(reminders.decode())]
+
+async def check_due_reminders(redis, reminders, bot):
+        now = datetime.utcnow().replace(tzinfo=UTC).astimezone(local)
+
+        for r in reminders:
+            if r.when <= now:
+                await bot.message("#eletrotupiniquim", f"{r.who}: Lembrete {r.what}")
+                reminders.remove(r)
+
+        save_reminders(redis, reminders)