#!/bin/env python

# -------------------------------------------------------------------------------
# This is a basic implementation of comments with a flat structure,
# as described in my article:
# https://blog.miguelgrinberg.com/post/implementing-user-comments-with-sqlalchemy
# -------------------------------------------------------------------------------

from datetime import datetime
from flask import Flask
from flask_sqlalchemy import SQLAlchemy

app = Flask(__name__)
app.config['SQLALCHEMY_DATABASE_URI'] = 'sqlite://'
app.config['SQLALCHEMY_TRACK_MODIFICATIONS'] = False

db = SQLAlchemy(app)


class Comment(db.Model):
    id = db.Column(db.Integer, primary_key=True)
    text = db.Column(db.String(140))
    author = db.Column(db.String(32))
    timestamp = db.Column(db.DateTime(), default=datetime.utcnow, index=True)


# create the database and insert a few comments
db.create_all()
c1 = Comment(text='hello1', author='bob')
c2 = Comment(text='hello2', author='alice')
c3 = Comment(text='hello3', author='bob')
c4 = Comment(text='hello4', author='alice')
db.session.add_all([c1, c2, c3, c4])
db.session.commit()


# display the comments
for comment in Comment.query.order_by(Comment.timestamp.asc()):
    print('{}: {}'.format(comment.author, comment.text))