from typing import Literal, TypedDict

MaintTaskType = Literal["empty_bin", "clean_brush", "clean_filter", "firmware_update", "sensor_check"]

class MaintReminder(TypedDict):
    should_remind: bool
    urgency: Literal["low", "medium", "high"]
    reason: str


def decide_maintenance_reminder(task_type: MaintTaskType, days_since_last: int) -> MaintReminder:
    """Heuristic for when to remind about simple maintenance tasks."""
    if task_type == "empty_bin":
        if days_since_last >= 1:
            return {"should_remind": True, "urgency": "high", "reason": "Dust bin should be emptied daily."}
        return {"should_remind": False, "urgency": "low", "reason": "Bin recently emptied."}

    if task_type == "clean_brush":
        if days_since_last >= 7:
            return {"should_remind": True, "urgency": "medium", "reason": "Brush should be cleaned weekly."}
        return {"should_remind": False, "urgency": "low", "reason": "Brush cleaning not yet due."}

    if task_type == "clean_filter":
        if days_since_last >= 14:
            return {"should_remind": True, "urgency": "medium", "reason": "Filter cleaning recommended every 2 weeks."}
        return {"should_remind": False, "urgency": "low", "reason": "Filter cleaning not yet due."}

    if task_type == "sensor_check":
        if days_since_last >= 30:
            return {"should_remind": True, "urgency": "low", "reason": "Monthly sensor self-check is due."}
        return {"should_remind": False, "urgency": "low", "reason": "Sensor check recently performed."}

    if task_type == "firmware_update":
        if days_since_last >= 60:
            return {"should_remind": True, "urgency": "low", "reason": "Check for firmware updates every few months."}
        return {"should_remind": False, "urgency": "low", "reason": "Firmware update not yet necessary."}

    return {"should_remind": False, "urgency": "low", "reason": "Unknown task type."}


if __name__ == "__main__":
    tests = [
        ("empty_bin", 2),
        ("clean_brush", 8),
        ("clean_filter", 10),
        ("sensor_check", 31),
        ("firmware_update", 90),
    ]
    for t, d in tests:
        print(t, d, "->", decide_maintenance_reminder(t, d))