application.py

from flask import Flask, request, render_template, redirect, jsonify, session, url_for, flash
from flask_socketio import SocketIO, emit
# My own / Flask Mega-Tutorial
from config import Config
from flask_sqlalchemy import SQLAlchemy
from flask_migrate import Migrate
from flask_login import LoginManager, login_required, login_user, logout_user, current_user
from werkzeug.urls import url_parse
import os


app = Flask(__name__)
app.config.from_object(Config)
socketio = SocketIO(app)
# Mega-Tutorial
db = SQLAlchemy(app)
migrate = Migrate(app, db)
login = LoginManager(app)
login.login_view = 'login'

# Need render_as_batch for sqlite3, or else database migrations with ALTER will fail.
with app.app_context():
    if db.engine.url.drivername == 'sqlite':
        migrate.init_app(app, db, render_as_batch=True)
    else:
        migrate.init_app(app, db)


from models import User, Post, Channel
from forms import LoginForm, SignUpForm, NewChannelForm, NewPostForm
from datetime import datetime, timedelta

@app.route("/ensureLogIn")
def is_user_logged_in():
    if 'logged_in' in session and session['logged_in']:
        response = {'logged_in': True}
    else:
        session['logged_in'] = False
        response = {'logged_in': False}
    print(response, flush=True)
    return jsonify(response)


@app.route("/")
@app.route("/index")
def index():
    return render_template("home.html", title="Home")


@app.route("/channels")
@login_required
def channels():
    return redirect(url_for("channel", channel_name="general"))


@app.route("/channels/<string:channel_name>", methods=["GET", "POST"])
@login_required
def channel(channel_name):
    new_channel_form = NewChannelForm()
    new_post_form = NewPostForm()
    if request.method == "POST":
        if new_channel_form.submit.data and new_channel_form.validate_on_submit():
            channel = Channel(name=new_channel_form.channel_name.data)
            db.session.add(channel)
            db.session.commit()
            new_channel_form.channel_name.data = ""
            return redirect(url_for("channel", channel_name=channel_name))
        elif new_post_form.submit.data and new_post_form.validate_on_submit():
            post = Post(body=new_post_form.post_body.data,
                        timestamp=datetime.utcnow(),
                        user_id=current_user.id,
                        channel_id=Channel.query.filter_by(name=channel_name).first().id)
            db.session.add(post)
            db.session.commit()
            new_post_form.post_body.data = ""
            return redirect(url_for("channel", channel_name=channel_name))

    channels = Channel.query.all()
    if not any(channel_name == channel.name for channel in channels):
        return redirect(url_for("channels"))
    cur_channel = Channel.query.filter_by(name=channel_name).first()
    posts = cur_channel.posts
    return render_template("channel.html",
                           new_channel_form=new_channel_form,
                           new_post_form=new_post_form,
                           channels=channels,
                           posts=posts)


@socketio.on("message sent")
def message_emitter(post):
    print("@socketio.on(message sent)", flush=True)
    print(post, flush=True)

    body = post["body"]
    emit("message received", {"body": body}, broadcast=True)



# def get_posts_with_time_passed(posts):
#     now = datetime.utcnow()
#     for post in posts:
#         delta = now - post.timestamp
#         if timedelta(seconds=0) <= delta < timedelta(minutes=1):
#             post.time_passed = "1 min ago"
#         elif timedelta(minutes=0) <= delta < timedelta(minutes=60):
#             minutes = delta.totalseconds() // 60
#             post.time_passed = f"{minutes} minutes ago"
#         else:
#             post.time_passed = "Error occurred"
#         print(post.time_passed, flush=True)
#     return posts



@app.route("/login", methods=["GET", "POST"])
def login():
    if current_user.is_authenticated:
        return redirect(url_for("index"))
    form = LoginForm()
    if form.validate_on_submit():
        user = User.query.filter_by(username=form.username.data).first()
        if user is None or not user.check_password(form.password.data):
            flash("Invalid username or password")
            return redirect(url_for("login"))
        login_user(user, remember=form.remember_me.data)
        next_page = request.args.get("next")
        if not next_page or url_parse(next_page).netloc != '':
            next_page = url_for("channels")
        return redirect(next_page)
    return render_template("login.html", title="Log In", form=form)


@app.route("/signup", methods=["GET", "POST"])
def signup():
    if current_user.is_authenticated:
        return redirect(url_for("index"))
    form = SignUpForm()
    if form.validate_on_submit():
        filepath = form.avatar.data.replace("http://127.0.0.1:5000", "")
        user = User(avatar=filepath, username=form.username.data, email=form.email.data)
        user.set_password(form.password.data)
        db.session.add(user)
        db.session.commit()
        return redirect("/login")
    monster_files = ["/static/images/monsters/" + filename for filename in os.listdir("static/images/monsters")]
    return render_template("signup.html", title="Sign Up", form=form, monster_files=monster_files)


@app.route("/logout")
def logout():
    logout_user()
    return redirect(url_for("index"))