from flask_sqlalchemy import SQLAlchemy 
from flask import Flask

app = Flask(__name__)
app.config['SQLALCHEMY_DATABASE_URI'] = 'sqlite:///drinks.db'
db = SQLAlchemy(app)


class DrinkIngredient(db.Model):
    id = db.Column(db.Integer, primary_key=True)
    ingredient_id = db.Column(db.Integer, db.ForeignKey('ingredient.id'))
    drink_id = db.Column(db.Integer, db.ForeignKey('drink.id'))
    ingredient = db.relationship("Ingredient", uselist=False)
    drink = db.relationship("Drink", uselist=False)
    units = db.Column(db.Float)

    def __repr__(self):
        return '<DrinkIngredient %f units of %s>' % (self.units, self.drink.name)


class Drink(db.Model):
    __tablename__ = 'drink'
    id = db.Column(db.Integer, primary_key=True)
    name = db.Column(db.String(64), index=True, unique=True)
    Ingredients = db.relationship('DrinkIngredient')
 
    def __init__(self, name):
        self.name = name
 
    def __repr__(self):
        return '<Drink %r>' % (self.name)
 
 
class Ingredient(db.Model):
    __tablename__ = 'ingredient'
    id = db.Column(db.Integer, primary_key=True)
    name = db.Column(db.String(140))
 
    def __init__(self, name):
        self.name = name
 
    def __repr__(self):
        return '<Ingredient %r>' % (self.name)