"""Plan model. Tier limits live in `config` JSON, editable in admin without redeploy."""
from datetime import datetime
from app.utils.time import utcnow
from sqlalchemy import JSON
from app.extensions import db


class Plan(db.Model):
    __tablename__ = "plans"

    id = db.Column(db.BigInteger().with_variant(db.Integer, "sqlite"), primary_key=True, autoincrement=True)
    slug = db.Column(db.String(40), unique=True, nullable=False)         # free|basic|pro|business
    name = db.Column(db.String(80), nullable=False)
    price_monthly_cents = db.Column(db.Integer, nullable=False, default=0)
    stripe_price_id = db.Column(db.String(80), nullable=True)
    config = db.Column(JSON, nullable=False, default=dict)               # limits (Section 6)
    is_active = db.Column(db.Boolean, nullable=False, default=True)
    sort_order = db.Column(db.Integer, nullable=False, default=0)

    created_at = db.Column(db.DateTime, default=utcnow, nullable=False)
    updated_at = db.Column(db.DateTime, default=utcnow,
                           onupdate=utcnow, nullable=False)

    users = db.relationship("User", back_populates="tier", lazy="dynamic")

    def limit(self, key, default=None):
        """Read a single limit from config JSON."""
        return (self.config or {}).get(key, default)

    def __repr__(self):
        return f"<Plan {self.slug}>"