main.py

from datetime import date
from flask import Flask, abort, render_template, redirect, url_for, flash
from flask_bootstrap import Bootstrap5
from flask_ckeditor import CKEditor
from flask_login import UserMixin, login_user, LoginManager, current_user, logout_user
from flask_sqlalchemy import SQLAlchemy
from functools import wraps
from werkzeug.security import generate_password_hash, check_password_hash
from sqlalchemy.orm import relationship
# Import your forms from the forms.py
from forms import CreatePostForm, RegisterForm, LoginForm, CommentForm
import os


app = Flask(__name__)
app.config['SECRET_KEY'] = os.getenv('FLASK_SECRET_KEY')
ckeditor = CKEditor(app)
Bootstrap5(app)


'''
admin details:
admin@email.com
pass: 1112
'''


login_manager = LoginManager()
login_manager.init_app(app)

# Create a user_loader callback
@login_manager.user_loader
def load_user(user_id):
    return User.query.get(int(user_id))

# CONNECT TO DB
app.config['SQLALCHEMY_DATABASE_URI'] = os.getenv('POST_DATABASE_URI', 'sqlite:///posts.db')
db = SQLAlchemy()
db.init_app(app)


# CONFIGURE TABLE
class BlogPost(db.Model):
    __tablename__ = "blog_posts"
    id = db.Column(db.Integer, primary_key=True)
    # Create Foreign Key, "users.id" the users refers to the tablename of User.
    author_id = db.Column(db.Integer, db.ForeignKey("users.id"))
    # Create reference to the User object. The "posts" refers to the posts property in the User class.
    author = relationship("User", back_populates="posts")
    title = db.Column(db.String(250), unique=True, nullable=False)
    subtitle = db.Column(db.String(250), nullable=False)
    date = db.Column(db.String(250), nullable=False)
    body = db.Column(db.Text, nullable=False)
    img_url = db.Column(db.String(250), nullable=False)
    # Parent relationship to the comments
    comments = relationship("Comment", back_populates="parent_post")


# Create a User table for all your registered users
class User(UserMixin, db.Model):
    __tablename__ = "users"
    id = db.Column(db.Integer, primary_key=True)
    email = db.Column(db.String(100), unique=True)
    password = db.Column(db.String(100))
    name = db.Column(db.String(100))
    # This will act like a list of BlogPost objects attached to each User.
    # The "author" refers to the author property in the BlogPost class.
    posts = relationship("BlogPost", back_populates="author")
    # Parent relationship: "comment_author" refers to the comment_author property in the Comment class.
    comments = relationship("Comment", back_populates="comment_author")


# Create a table for the comments on the blog posts
class Comment(db.Model):
    __tablename__ = "comments"
    id = db.Column(db.Integer, primary_key=True)
    text = db.Column(db.Text, nullable=False)
    # Child relationship:"users.id" The users refers to the tablename of the User class.
    # "comments" refers to the comments property in the User class.
    author_id = db.Column(db.Integer, db.ForeignKey("users.id"))
    comment_author = relationship("User", back_populates="comments")
    # Child Relationship to the BlogPosts
    post_id = db.Column(db.Integer, db.ForeignKey("blog_posts.id"))
    parent_post = relationship("BlogPost", back_populates="comments")

with app.app_context():
    db.create_all()


#Create admin-only decorator
def admin_only(f):
    @wraps(f)
    def decorated_function(*args, **kwargs):
        #If email isn't that of admin then return abort with 403 error
        if not current_user.is_authenticated or current_user.email != 'admin@email.com':
            return abort(403)
        #Otherwise continue with the route function
        return f(*args, **kwargs)        
    return decorated_function


@app.route('/register', methods=['POST', 'GET'])
def register():
    form = RegisterForm()
    if form.validate_on_submit():
        # hased password
        password = generate_password_hash(
            password=form.password.data,
            method='pbkdf2:sha256',
            salt_length=8,
        )
        email = form.email.data
        name = form.name.data
        
        # checking if the user already exists
        user = db.session.execute(db.select(User).where(User.email==email)).scalar()
        if user: 
            # the email exists
            flash('The email already exists. Please login.')
            return redirect(url_for('login'))
        
        new_user = User(
            email=email,
            password=password,
            name=name
        )

        db.session.add(new_user)
        db.session.commit()
        print(f'entered to db: {password}, {email}, {name}')

        login_user(new_user)
        return redirect(url_for('get_all_posts'))

    return render_template('register.html', form=form, current_user=current_user)


# TODO: Retrieve a user from the database based on their email. 
@app.route('/login', methods=['GET', 'POST'])
def login():
    form = LoginForm()

    if form.validate_on_submit():

        email = form.email.data
        password = form.password.data

        # finding the user with the same email
        user = db.session.execute(db.select(User).where(User.email==email)).scalar()

        if not user:
            # i.e. no user with that email id exists. go register
            flash("You don't seem to have an account with this email. Kindly register.")
            return redirect(url_for('register'))
        
        elif not check_password_hash(password=password, pwhash=user.password):
            # if the password entered is incorrect
            flash("Uh ho! That doesn't seem right. Your password is wrong.")
            return redirect(url_for('login'))
        
        else:
            # user exits and password is right
            print('login done')
            login_user(user)
            return redirect(url_for('get_all_posts'))

    return render_template("login.html", form=form, current_user=current_user)


@app.route('/logout')
def logout():
    logout_user()
    return redirect(url_for('get_all_posts'))


@app.route('/')
def get_all_posts():
    result = db.session.execute(db.select(BlogPost))
    posts = result.scalars().all()
    return render_template("index.html", all_posts=posts, current_user=current_user)


# TODO: Allow logged-in users to comment on posts
@app.route("/post/<int:post_id>", methods=['GET', 'POST'])
def show_post(post_id):
    form = CommentForm()
    requested_post = db.get_or_404(BlogPost, post_id)
    # Only allow logged-in users to comment on posts
    if form.validate_on_submit():
        
        if not current_user.is_authenticated:
            flash("You need to login or register to comment.")
            return redirect(url_for("login"))

        new_comment = Comment(
            text=form.comment.data,
            comment_author=current_user,
            post_id=requested_post.id
        )
        db.session.add(new_comment)
        db.session.commit()

    return render_template("post.html", post=requested_post, current_user=current_user, form=form)


# TODO: Use a decorator so only an admin user can create a new post
@app.route("/new-post", methods=["GET", "POST"])
@admin_only
def add_new_post():
    form = CreatePostForm()
    if form.validate_on_submit():
        new_post = BlogPost(
            title=form.title.data,
            subtitle=form.subtitle.data,
            body=form.body.data,
            img_url=form.img_url.data,
            author=current_user,
            date=date.today().strftime("%B %d, %Y")
        )
        db.session.add(new_post)
        db.session.commit()
        return redirect(url_for("get_all_posts"))
    return render_template("make-post.html", form=form, current_user=current_user)


# TODO: Use a decorator so only an admin user can edit a post
@app.route("/edit-post/<int:post_id>", methods=["GET", "POST"])
@admin_only
def edit_post(post_id):
    post = db.get_or_404(BlogPost, post_id)
    edit_form = CreatePostForm(
        title=post.title,
        subtitle=post.subtitle,
        img_url=post.img_url,
        author=post.author,
        body=post.body
    )
    if edit_form.validate_on_submit():
        post.title = edit_form.title.data
        post.subtitle = edit_form.subtitle.data
        post.img_url = edit_form.img_url.data
        post.author = current_user
        post.body = edit_form.body.data
        db.session.commit()
        return redirect(url_for("show_post", post_id=post.id))
    return render_template("make-post.html", form=edit_form, is_edit=True, current_user=current_user)


# TODO: Use a decorator so only an admin user can delete a post
@app.route("/delete/<int:post_id>")
@admin_only
def delete_post(post_id):
    post_to_delete = db.get_or_404(BlogPost, post_id)
    db.session.delete(post_to_delete)
    db.session.commit()
    return redirect(url_for('get_all_posts'))


@app.route("/about")
def about():
    return render_template("about.html", current_user=current_user)


@app.route("/contact")
def contact():
    return render_template("contact.html", current_user=current_user)



if __name__ == "__main__":
    app.run(debug=False)