from pydantic import BaseModel
from typing import List, Dict, Optional


class DeliveryRequest(BaseModel):
    id: int
    destination: int
    deadline: float          # time units by which delivery must complete
    reward_value: float = 10.0


class Observation(BaseModel):
    current_location: int
    pending_deliveries: List[Dict]   # list of DeliveryRequest dicts
    time: float
    fuel: float
    traffic: Dict                    # edge -> multiplier, e.g. {(0,1): 1.5}


class Action(BaseModel):
    next_node: int


class Reward(BaseModel):
    value: float


class StepResult(BaseModel):
    observation: Observation
    reward: Reward
    done: bool
    info: Dict