from pydantic import BaseModel, Field
from typing import Literal, Optional
from datetime import date


class RouteDecision(BaseModel):
    """
    Structured outcome of a routing decision.
    Modified to support detailed chart intent extraction.
    """

    route: Literal["CHAT", "CHART"]
    metric: Optional[str] = Field(None, description="Target metric: pace, hr, distance, etc.")
    period: Optional[str] = Field(None, description="Temporal scope: last_week, current_week, all_time")
    target_date: Optional[date] = Field(None, description="Specifically resolved date (e.g. for 'last week')")