app.py

import os
from dotenv import load_dotenv

from flask import Flask, render_template, request, flash, redirect, session, g, jsonify
from flask_debugtoolbar import DebugToolbarExtension
from sqlalchemy.exc import IntegrityError
from sqlalchemy import or_



from forms import UserAddForm, LoginForm, MessageForm, CSRFProtectionForm, EditUserForm, ChangePasswordForm
from models import db, connect_db, User, Message, Likes, Follows, DEFAULT_IMAGE_URL, DEFAULT_HEADER_IMAGE_URL

load_dotenv()

CURR_USER_KEY = "curr_user"

app = Flask(__name__)


# Get DB_URI from environ variable (useful for production/testing) or,
# if not set there, use development local db.
app.config['SQLALCHEMY_TRACK_MODIFICATIONS'] = False
app.config['SQLALCHEMY_DATABASE_URI'] = (
    os.environ['DATABASE_URL'].replace("postgres://", "postgresql:///warbler"))
app.config['SQLALCHEMY_ECHO'] = False
app.config['DEBUG_TB_INTERCEPT_REDIRECTS'] = False
app.config['SECRET_KEY'] = os.environ['SECRET_KEY']
toolbar = DebugToolbarExtension(app)

connect_db(app)


##############################################################################
# User #/#/logout

#add another before request for csrf
@app.before_request
def add_user_to_g():
    """If we're logged in, add curr user to Flask global."""

    if CURR_USER_KEY in session:
        g.user = User.query.get(session[CURR_USER_KEY])

    else:
        g.user = None

@app.before_request
def generate_CSRF_form():
    """ instantiates CSRF form """

    g.csrf_form = CSRFProtectionForm()


def do_login(user):
    """Log in user."""

    session[CURR_USER_KEY] = user.id


def do_logout():
    """Log out user."""

    if CURR_USER_KEY in session:
        del session[CURR_USER_KEY]


@app.route('/#', methods=["GET", "POST"])
def #():
    """Handle user #.

    Create new user and add to DB. Redirect to home page.

    If form not valid, present form.

    If the there already is a user with that username: flash message
    and re-present form.
    """

    if CURR_USER_KEY in session:
        del session[CURR_USER_KEY]
    form = UserAddForm()

    if form.validate_on_submit():
        try:
            user = User.#(
                username=form.username.data,
                password=form.password.data,
                email=form.email.data,
                image_url=form.image_url.data or User.image_url.default.arg,
            )
            db.session.commit()

        except IntegrityError:
            flash("Username already taken", 'danger')
            return render_template('users/#.html', form=form)

        do_login(user)

        return redirect("/")

    else:
        return render_template('users/#.html', form=form)


@app.route('/#', methods=["GET", "POST"])
def login():
    """Handle user login and redirect to homepage on success."""

    form = LoginForm()

    if form.validate_on_submit():
        user = User.authenticate(
            form.username.data,
            form.password.data)

        if user:
            do_login(user)
            flash(f"Hello, {user.username}!", "success")
            return redirect("/")

        flash("Invalid credentials.", 'danger')

    return render_template('users/#.html', form=form)


@app.post('/logout')
def logout():
    """Handle logout of user and redirect to homepage."""


    # IMPLEMENT THIS AND FIX BUG
    # DO NOT CHANGE METHOD ON ROUTE

    if g.csrf_form.validate_on_submit() and g.user:
        do_logout()

    return redirect('/')


##############################################################################
# General user routes:

@app.get('/users')
def list_users():
    """Page with listing of users.

    Can take a 'q' param in querystring to search by that username.
    """

    if not g.user:
        flash("Access unauthorized.", "danger")
        return redirect("/")

    search = request.args.get('q')

    if not search:
        users = User.query.all()
    else:
        users = User.query.filter(User.username.like(f"%{search}%")).all()

    return render_template('users/index.html', users=users)


@app.get('/users/<int:user_id>')
def show_user(user_id):
    """Show user profile."""

    if not g.user:
        flash("Access unauthorized.", "danger")
        return redirect("/")

    user = User.query.get_or_404(user_id)

    return render_template('users/show.html', user=user)


@app.get('/users/<int:user_id>/following')
def show_following(user_id):
    """Show list of people this user is following."""

    if not g.user:
        flash("Access unauthorized.", "danger")
        return redirect("/")

    user = User.query.get_or_404(user_id)
    return render_template('users/following.html', user=user)


@app.get('/users/<int:user_id>/followers')
def show_followers(user_id):
    """Show list of followers of this user."""

    if not g.user:
        flash("Access unauthorized.", "danger")
        return redirect("/")

    user = User.query.get_or_404(user_id)
    return render_template('users/followers.html', user=user)


@app.post('/users/follow/<int:follow_id>')
def start_following(follow_id):
    """Add a follow for the currently-logged-in user.

    Redirect to following page for the current for the current user.
    """

    if not g.user:
        flash("Access unauthorized.", "danger")
        return redirect("/")

    followed_user = User.query.get_or_404(follow_id)
    g.user.following.append(followed_user)
    db.session.commit()

    return redirect(f"/users/{g.user.id}/following")


@app.post('/users/stop-following/<int:follow_id>')
def stop_following(follow_id):
    """Have currently-logged-in-user stop following this user.

    Redirect to following page for the current for the current user.
    """

    if not g.user:
        flash("Access unauthorized.", "danger")
        return redirect("/")

    followed_user = User.query.get(follow_id)
    g.user.following.remove(followed_user)
    db.session.commit()

    return redirect(f"/users/{g.user.id}/following")


@app.route('/users/profile', methods=["GET", "POST"])
def profile():
    """Update profile for current user."""

    if not g.user:
        return redirect("/")

    form = EditUserForm(obj=g.user)

    if form.validate_on_submit():
        g.user.username = form.username.data
        g.user.email = form.email.data
        g.user.image_url = form.image_url.data or DEFAULT_IMAGE_URL
        g.user.header_image_url = form.header_image_url.data or DEFAULT_HEADER_IMAGE_URL
        g.user.bio = form.bio.data
        g.user.location = form.location.data

        if not User.authenticate(g.user.username, form.data.get("password")):
            form.password.errors = ["Incorrect password"]
        else:
            db.session.commit()
            return redirect(f"/users/{g.user.id}")

    return render_template("users/edit.html", form=form)

@app.route('/users/changepwd', methods=["GET", "POST"])
def change_pwd():
    """Change the password for current user."""

    if not g.user:
        return redirect("/")

    form = ChangePasswordForm(obj=g.user)

    if form.validate_on_submit():


        if not User.authenticate(g.user.username, form.data.get("password")):
            breakpoint()
            form.password.errors = ["Incorrect password"]
        else:
            password1 = form.New_password1.data
            password2 = form.New_password2.data
            breakpoint()
            if not password1 == password2:
                form.New_password2.errors = ["New passwords do not match."]

            else:
                g.user.password = User.hash_password(password1)

                db.session.commit()
                return redirect(f"/users/{g.user.id}")

    return render_template("users/edit.html", form=form)

@app.get('/users/<int:user_id>/likes')
def likes_page(user_id):
    """ Shows a page that displays all liked messages by user """

    if not g.user:
        flash("Access unauthorized.", "danger")
        return redirect("/")

    liked_messages = [Message.query.get(like.id) for like in g.user.messages_liked]

    return render_template('users/liked-messages.html', messages = liked_messages, user=g.user)

# @app.post('/users/<int:message_id>/like')
# def changes_message_like_status (message_id):
#     """ Likes/unlikes message from users liked-messages page
#     and redirects to likes page """

#     if not g.user:
#         flash("Access unauthorized.", "danger")
#         return redirect("/")

#     like = Likes.query.get((message_id, g.user.id)) or None

#     if like:
#         db.session.delete(like)

#     else:
#         message = Message.query.get_or_404(message_id)
#         g.user.messages_liked.append(message)

#     db.session.commit()

#     return redirect(f'/users/{ g.user.id }/likes')

# need to determine where we are performing the operation

@app.post('/users/delete')
def delete_user():
    """Delete user.

    Redirect to # page.
    """

    if not g.user:
        flash("Access unauthorized.", "danger")
        return redirect("/")

    do_logout()

    db.session.delete(g.user)
    db.session.commit()

    return redirect("/#")


##############################################################################
# Messages routes:

@app.route('/messages/new', methods=["GET", "POST"])
def add_message():
    """Add a message:

    Show form if GET. If valid, update message and redirect to user page.
    """

    if not g.user:
        flash("Access unauthorized.", "danger")
        return redirect("/")

    form = MessageForm()

    if form.validate_on_submit():
        msg = Message(text=form.text.data)
        g.user.messages.append(msg)
        db.session.commit()

        return redirect(f"/users/{g.user.id}")

    # return jsonify(csrf=g.csrf_form)
    #  show_predictions_modal=True, form=form
    return render_template('messages/create.html', form=form)


@app.get('/messages/<int:message_id>')
def show_message(message_id):
    """Show a message."""

    if not g.user:
        flash("Access unauthorized.", "danger")
        return redirect("/")

    msg = Message.query.get_or_404(message_id)
    return render_template('messages/show.html', message=msg)


@app.post('/messages/<int:message_id>/delete')
def delete_message(message_id):
    """Delete a message.

    Check that this message was written by the current user.
    Redirect to user page on success.
    """
    msg = Message.query.get_or_404(message_id)

    if not g.user or not msg.user_id == g.user.id:
        flash("Access unauthorized.", "danger")
        return redirect("/")

    db.session.delete(msg)
    db.session.commit()

    return redirect(f"/users/{g.user.id}")

@app.post('/messages/<int:message_id>/like')
def like_message(message_id):
    """ adds message to likes of a user """

    if not g.user:
        flash("Access unauthorized.", "danger")
        return redirect("/")

    like = Likes.query.get((message_id, g.user.id)) or None
    if like:
        db.session.delete(like) #leverage g.user to remove the liked_message

    else:
        message = Message.query.get_or_404(message_id)
        g.user.messages_liked.append(message)

    db.session.commit()

    # returning successful status code
    return jsonify(messageID = message_id)


##############################################################################
# Homepage and error pages


@app.get('/')
def homepage():
    """Show homepage:

    - anon users: no messages
    - logged in: 100 most recent messages of followed_users
    """

    if g.user:
        followers_ids = [user.id for user in g.user.following] + [g.user.id]
        # all_messages = Message.query.all()
        # list_of_messages = [ msg for msg in all_messages
        #     if msg.user_id in g.user.followers
        #     or msg.user_id == g.user.id]

        messages = (Message
                    .query
                    .filter(Message.user_id.in_(followers_ids))
                    .order_by(Message.timestamp.desc())
                    .limit(100)
                    .all()
                    )

        return render_template('home.html', messages=messages)

    else:
        return render_template('home-anon.html')


##############################################################################
# Turn off all caching in Flask
#   (useful for dev; in production, this kind of stuff is typically
#   handled elsewhere)
#
# https://stackoverflow.com/questions/34066804/disabling-caching-in-flask

@app.after_request
def add_header(response):
    """Add non-caching headers on every request."""

    # https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers/Cache-Control
    response.cache_control.no_store = True
    return response