"""UserExerciseProgram model for per-user exercise programming.

Links a user to an exercise with a starting weight for the rep ladder.
"""

from datetime import datetime
from typing import Optional

from sqlmodel import Field, SQLModel


class UserExerciseProgram(SQLModel, table=True):
    """Per-user programming for a specific exercise.

    Attributes:
        id: Primary key, auto-incremented.
        user_id: FK to users table.
        exercise_id: FK to exercises table.
        starting_weight: Starting weight (e.g., "30 lbs", "BW").
        created_at: Timestamp when the record was created.
        updated_at: Timestamp of the last update.
    """

    __tablename__ = "user_exercise_programs"

    id: Optional[int] = Field(default=None, primary_key=True)
    user_id: int = Field(foreign_key="users.id", index=True)
    exercise_id: int = Field(foreign_key="exercises.id", index=True)
    starting_weight: str = Field(default="")
    created_at: datetime = Field(default_factory=datetime.utcnow)
    updated_at: datetime = Field(default_factory=datetime.utcnow)