add reminder schedule

modules/reminders.py

@@ -1,6 +1,8 @@
 import asyncio
 import logging
 import random
+from datetime import datetime, timedelta
+from zoneinfo import ZoneInfo
 
 from aiogram import Bot
 
@@ -15,14 +17,82 @@ QUESTIONS = (
 )
 
 
+class ReminderState:
+    def __init__(self) -> None:
+        self.last_manual_entry_at: datetime | None = None
+        self.changed = asyncio.Event()
+
+    def mark_manual_entry(self, timezone: ZoneInfo) -> None:
+        self.last_manual_entry_at = datetime.now(timezone)
+        self.changed.set()
+
+
+def _is_allowed_time(now: datetime, start_hour: int, end_hour: int) -> bool:
+    return start_hour <= now.hour < end_hour
+
+
+def _next_window_start(now: datetime, start_hour: int) -> datetime:
+    if now.hour < start_hour:
+        return now.replace(hour=start_hour, minute=0, second=0, microsecond=0)
+    tomorrow = now + timedelta(days=1)
+    return tomorrow.replace(hour=start_hour, minute=0, second=0, microsecond=0)
+
+
+def _move_to_allowed_time(now: datetime, start_hour: int, end_hour: int) -> datetime:
+    if _is_allowed_time(now, start_hour, end_hour):
+        return now
+    return _next_window_start(now, start_hour)
+
+
+def _next_reminder_at(
+    now: datetime,
+    state: ReminderState,
+    min_seconds: int,
+    max_seconds: int,
+    start_hour: int,
+    end_hour: int,
+) -> datetime:
+    if not _is_allowed_time(now, start_hour, end_hour):
+        candidate = _move_to_allowed_time(now, start_hour, end_hour)
+    else:
+        candidate = now + timedelta(seconds=random.randint(min_seconds, max_seconds))
+
+    if state.last_manual_entry_at:
+        candidate = max(candidate, state.last_manual_entry_at + timedelta(hours=1))
+
+    return _move_to_allowed_time(candidate, start_hour, end_hour)
+
+
 async def send_reminders(
     bot: Bot,
     user_ids: set[int],
     min_seconds: int,
     max_seconds: int,
+    start_hour: int,
+    end_hour: int,
+    timezone: ZoneInfo,
+    state: ReminderState,
 ) -> None:
     while True:
-        await asyncio.sleep(random.randint(min_seconds, max_seconds))
+        now = datetime.now(timezone)
+        next_reminder_at = _next_reminder_at(
+            now=now,
+            state=state,
+            min_seconds=min_seconds,
+            max_seconds=max_seconds,
+            start_hour=start_hour,
+            end_hour=end_hour,
+        )
+        sleep_seconds = max(0, (next_reminder_at - now).total_seconds())
+
+        try:
+            await asyncio.wait_for(state.changed.wait(), timeout=sleep_seconds)
+        except TimeoutError:
+            pass
+        else:
+            state.changed.clear()
+            continue
+
         question = random.choice(QUESTIONS)
 
         for user_id in user_ids: