from datetime import datetime, timezone

from flask_sqlalchemy import SQLAlchemy

db = SQLAlchemy()


class Sensor(db.Model):
    __tablename__ = "sensor"

    id = db.Column(db.Integer, primary_key=True)
    name = db.Column(db.String(128), nullable=False, unique=True)
    created_at = db.Column(db.DateTime, default=lambda: datetime.now(timezone.utc))

    readouts = db.relationship("SensorReadout", backref="sensor", lazy=True)


class SensorReadout(db.Model):
    __tablename__ = "sensor_readout"

    id = db.Column(db.Integer, primary_key=True)
    sensor_id = db.Column(db.Integer, db.ForeignKey("sensor.id"), nullable=False)
    type = db.Column(db.String(64), nullable=False)
    value = db.Column(db.Float, nullable=False)
    timestamp = db.Column(db.DateTime, default=lambda: datetime.now(timezone.utc))