server.py

"""Learndo: An assignment tracker/notification system"""

import os

from jinja2 import StrictUndefined

from flask import Flask, render_template, request, flash, redirect, session, jsonify, json
from flask_debugtoolbar import DebugToolbarExtension
from datetime import datetime, timedelta

from model import connect_to_db, db, User, Class, Assignment, Task, UserClass
from helper import *


app = Flask(__name__)

app.config['SECRET_KEY'] = os.environ.get("FLASK_SECRET_KEY", "abcdef")

app.jinja_env.undefined = StrictUndefined


@app.route('/')
def index():
    """Homepage with registration form and login link"""

    if session.get('user_id') != None:
        url = "/"+session['acct_type']+"/"+str(session['user_id'])+"/assignments"
        return redirect(url)
    else:
       return render_template("homepage.html")

############### REGISTRATION ###############

@app.route('/register', methods=['POST'])
def register_process():
    """Processes registration, creates a new user in db, and saves user info in session."""

    # Get form variables
    first = request.form.get("first")
    last = request.form.get("last")
    preferred = request.form.get("preferred")
    email = request.form.get("email")
    username = request.form.get("username")
    password = request.form.get("password")
    school = request.form.get("school")
    teacher = bool(request.form.get("teacher"))

    # Check to see if username is available
    if len(User.query.filter(User.username == username).all()) > 0:
        flash("That username is already in use. Please choose another.")
        return redirect('/register')

    if preferred == "":
        preferred = first + " " + last

    # Create a new user in the db
    new_teacher = User(is_teacher=teacher,
                       username=username,
                       password=password,
                       email=email,
                       first_name=first,
                       last_name=last,
                       display_name=preferred,
                       school=school)

    db.session.add(new_teacher)
    db.session.commit()

    # Save user info in session
    session["user_id"] = new_teacher.user_id
    session["acct_type"] = 'teacher'

    flash("Your teacher account has been created! Get started by setting up your classes.".format(username, password))
    
    return redirect("/teacher/{}/classes".format(new_teacher.user_id))


############### LOGIN / LOGOUT ###############

@app.route('/login', methods=['POST'])
def login_process():
    """Process login."""

    # Get form variables
    username = request.form["username"]
    password = request.form["password"]

    # Check for matching user and correct password
    user = User.query.filter_by(username=username).first()
    if not user:
        flash("No such user")
        return redirect("/")
    if user.password != password:
        flash("Incorrect password")
        return redirect("/")

    # Save user id and account type in session
    session["user_id"] = user.user_id

    if user.is_teacher:
        session["acct_type"] = 'teacher'
    else:
        session["acct_type"] = 'student'

    flash("Welcome, {}!".format(user.display_name))

    # Redirect to assignments list after log in
    if user.is_teacher:
        return redirect("/teacher/%s/assignments" % user.user_id)
    else:
        return redirect("/student/%s/assignments" % user.user_id)


@app.route('/logout')
def logout():
    """Log out."""

    del session["user_id"]
    del session["acct_type"]
    flash("You are logged out.")
    return redirect("/")


############### MANAGING CLASSES ###############
@app.route('/teacher/<int:user_id>/classes')
def manage_classes(user_id):
    """Shows class lists and student lists. Teacher can also add classes and students."""

    if session.get('user_id') == user_id:
        teacher = User.query.get(user_id) ## Can I make this a global variable or store in session?
        class_list = show_classes(teacher)
        return render_template("class_list.html", teacher=teacher, class_list=class_list)
    else:
        flash("You do not have access to that page.")
        return redirect("/")


@app.route('/new_class', methods=['POST'])
def create_class():
    """Adds new class to db"""

    #Get form variables
    user_id = request.form["teacher"]
    class_name = request.form.get("class_name")

    # Create a new class in db and add the teacher to the class.
    if session.get('acct_type', 0) == 'teacher':
        teacher = User.query.get(user_id)
        add_class(teacher, class_name)

        flash("{} has been added.".format(class_name))
        return redirect('/teacher/{}/classes'.format(user_id))
    
    else:
        flash("You are not authorized to make this change.")
        return redirect("/")


@app.route('/add_student', methods=['POST'])
def add_student():
    """Add a student by username to a class"""
    
    # Get variables from form
    username = request.form.get('username')
    class_id = request.form.get('class-id')
    teacher_id = request.form.get("teacher")

    new_class = Class.query.get(class_id)

    # Checks to see if username is already in use.
    try:
        user = User.query.filter(User.username == username).one()
        exists = True
    except:
        exists = False
        flash("There is no student with that username.")
        return redirect('/teacher/{}/classes'.format(teacher_id))

    if exists:
        if session.get('acct_type', 0) == 'teacher':
            user.classes.append(new_class)
            db.session.commit()
            flash("{} has been added to {}".format(user.first_name, new_class.class_name))
            
            return redirect('/teacher/{}/classes'.format(teacher_id))

        else:
            flash("You are not authorized to make this change.")
            return redirect("/")


@app.route('/delete_class', methods=["POST"])
def delete_class():
    """Deletes class from db when teacher clicks link in manage classes dashboard."""

    class_id = request.form.get('class_id')
    this_class = Class.query.get(class_id)

    users = this_class.users

    # Check to see if the user is the teacher of the class
    authorized = False
    for user in users:
        if user.is_teacher and user.user_id == session['user_id']:
            authorized = True

    if authorized:
        db.session.delete(this_class)
        db.session.commit()
        return "The class, {}, has been deleted.".format(this_class.class_name)

    else:
        return "You are not authorized to make this change."


@app.route('/remove_student', methods=["POST"])
def remove_student():
    """Deletes student from the class in the db."""

    student_id = request.form.get('user_id')
    class_id = request.form.get('class_id')

    user_class = UserClass.query.filter(UserClass.user_id==student_id, 
                                        UserClass.class_id==class_id).one()

    this_student = User.query.get(student_id)

    if session.get('acct_type', 0) == 'teacher':
        db.session.delete(user_class)
        db.session.commit()
        return "{} has been removed from that class.".format(this_student.display_name)

    else:
        return "You are not authorized to make this change."
    

@app.route('/new_student', methods=['POST'])
def create_student():
    """Teacher creates new student accounts and add them to classes simultaneously"""

    # Get form variables
    first = request.form.get("first")
    last = request.form.get("last")
    preferred = request.form.get("preferred")
    email = request.form.get("email")
    username = request.form.get("username")
    password = request.form.get("password")
    class_id = request.form.get("class-id")
    teacher_id = request.form.get("teacher")

    # Check to see if username is available
    if len(User.query.filter(User.username == username).all()) > 0:
        flash("That username is already in use. Please choose another.")
        return redirect('/teacher/{}/classes'.format(teacher_id))

    if email == "":
        email = None

    if preferred == "":
        preferred = first

    if session.get('acct_type', 0) == 'teacher':
        teacher = User.query.get(teacher_id)

        # Creates new user in db
        new_student = User(is_teacher=False,
                           username=username,
                           password=password,
                           email=email,
                           first_name=first,
                           last_name=last,
                           display_name=preferred,
                           school=teacher.school)
        db.session.add(new_student)
        db.session.commit()
        new_student.classes.append(Class.query.get(class_id))
        db.session.commit()
        
        flash("A new account has been created for {} with the username {} and password {}.".format(preferred, username, password))
        return redirect('/teacher/{}/classes'.format(teacher_id))

    else:
        flash("You are not authorized to make this change.")
        return redirect("/")


############### PROFILES ###############
@app.route('/profile/<int:user_id>')
def load_profile(user_id):
    """Renders template for profile page for both students and teachers"""

    user = User.query.get(user_id)

    if user.is_teacher:
        acct_type = 'teacher'
    else:
        acct_type = 'student'

    my_classes = []
    for each_class in user.classes:
        my_classes.append(each_class.class_name)

    if access_profile(user_id) == True:
        return render_template("profile.html", user=user, my_classes=my_classes, acct_type=acct_type)
    else:
        flash("You do not have access to that page.")
        return redirect("/")


@app.route('/edit_profile', methods=['POST'])
def edit_profile():
    """Users can change their profile information"""

    # Get form variables
    first = request.form.get("first")
    last = request.form.get("last")
    preferred = request.form.get("preferred")
    email = request.form.get("email")
    username = request.form.get("username")
    password = request.form.get("password")
    school = request.form.get("school")
    user_id = request.form.get("user_id")

    if email == "" or "None":
            email = None

    if preferred == "" or "None":
            preferred = first

    user = User.query.get(user_id)

    # Check to see if username is available
    if len(User.query.filter(User.username == username).all()) > 0 and username != user.username:
        flash("That username is already in use. Please choose another.")
        return redirect('/profile/{}'.format(user_id))
    else:
        user.first_name = first
        user.last_name = last
        user.display_name = preferred
        user.email = email
        user.username = username
        user.password = password
        user.school = school

        db.session.commit()
    
        flash("Your changes have been successfully saved!")
        return redirect('/profile/{}'.format(user_id))


############### ASSIGNMENTS ###############
@app.route('/teacher/<int:user_id>/assignments')
def show_teacher_assignments(user_id):
    """Lists assignments created by a teacher"""

    if session.get('user_id') == user_id:
        return render_template("tassignments.html", tid=session['user_id'])
    else:
        flash("You do not have access to that page.")
        return redirect("/")


@app.route('/student/<int:user_id>/assignments')
def test_student_assignments(user_id):
    """Lists assignments assigned to a student"""

    if session.get('user_id') == user_id:
        return render_template("sassignments-js.html", sid=session['user_id'])

    else:
        flash("You do not have access to that page.")
        return redirect("/")


@app.route('/list.json')
def sort_by_assigned():
    """Returns a list of assignments for the user_id in session as a JSONifiable array of objects."""

    if session.get('acct_type') == 'student':
        user = User.query.get(session['user_id'])
        assignments_list = user.assignments
        assignments = create_assignment_list(assignments_list)
        return jsonify(assignments)
    if session.get('acct_type') == 'teacher':
        user = User.query.get(session['user_id'])
        assignments_list = Task.query.filter(Task.created_by == session['user_id']).all()
        assignments = create_assignment_list(assignments_list)
        return jsonify(assignments)


@app.route('/student/<int:student_id>/assignments/<int:assign_id>')
def view_student_assignment(student_id, assign_id):
    """Shows assignment information to student with a form to check that an 
    assignment is complete"""

    assignment = Assignment.query.get(assign_id)
    task = assignment.task
    date_obj = task.due_date
    due_date = date_obj.strftime("%A %m/%d/%y %I:%M %p")
    assigned_on = assignment.assigned.strftime("%A %m/%d/%y %I:%M %p") # Stores date assigned

    # double-checks authorization before rendering template
    user_id = session['user_id']

    if user_id == student_id:
        assignment.viewed = datetime.now()
        db.session.commit()
        return render_template("sassignment_view.html", task=task, 
                                                        due_date=due_date,
                                                        assignment=assignment, 
                                                        assigned_on=assigned_on)
    else:
        flash("You do not have access to that page.")
        return redirect("/")


@app.route('/completed', methods=["POST"])
def complete_assignment():

    completed = request.form.get("completed")
    assign_id = request.form.get("assign_id")

    assignment = Assignment.query.get(assign_id)

    if completed:
        assignment.completed = datetime.now()
        assignment.viewed = datetime.now()
        flash("Congratulations on finishing! Your teacher has been notified.")
    else:
        assignment.completed = None
        assignment.viewed = datetime.now()
        flash("Your teacher has been notified that you are still working.")

    db.session.commit()

    return redirect("/student/{}/assignments/{}".format(assignment.student_id, assign_id))


@app.route('/new_assignment')
def show_assignment_form():
    """Form for creating new assignments"""

    user = User.query.get(session['user_id'])

    if user.is_teacher:
        return render_template("new_assignment.html", user=user)
    else:
        flash("You do not have access to that page.")
        return redirect("/")


@app.route('/create_assignment', methods=["POST"])
def create_assignment():
    """Adds info from assignment form into the tasks table in the db."""

    title = request.form.get("title")
    goal = request.form.get("goal")
    directions = request.form.get("directions")
    link = request.form.get("link")
    month = request.form.get("month")
    day = request.form.get("day")
    year = request.form.get("year")
    hour = request.form.get("hour")
    minute = request.form.get("minute")
    ampm = request.form.get("ampm")
    teacher_id = request.form.get("teacher_id")

    date_string = "{}/{}/{} {}:{} {}".format(month, day, year, hour, minute, ampm)
    due_date = datetime.strptime(date_string, "%m/%d/%y %I:%M %p")

    user = User.query.get(session['user_id'])
    #FIX ME: Use session['acct_type'] instead
    if user.is_teacher:

        new_task = Task(created_by=teacher_id,
                        title=title,
                        goal=goal,
                        directions=directions,
                        link=link,
                        due_date=due_date)

        db.session.add(new_task)
        db.session.commit()

        task_id = new_task.task_id

        return redirect("/teacher/{}/assignments/{}".format(teacher_id, task_id))

    else:
        flash("You are not authorized to make this change.")
        return redirect("/")


@app.route('/teacher/<int:teacher_id>/assignments/<int:task_id>')
def view_assignment(teacher_id, task_id):
    """Shows assignment information, assign button or class assigned to, and list of students
    working on that assignment and their progress"""

    task = Task.query.get(task_id)
    date_obj = task.due_date
    due_date = date_obj.strftime("%A %m/%d/%y %I:%M %p")

    # Creates a class list for the dropdown menu in the assignment form
    created_by = task.user
    class_list = show_classes(created_by)

    # Checks to see if this task has been assigned by creating a list of assignment objects
    assignment_list = Assignment.query.filter(Assignment.task_id == task_id).order_by(Assignment.student_id.desc()).all()

    if assignment_list:
        class_name = task.assigned_class.class_name # Queries db (a lot) to find the name of the class it is assigned to
        assigned_on = assignment_list[0].assigned.strftime("%A %m/%d/%y %I:%M %p") # Stores date assigned
        progress = report_student_progress(task, assignment_list) # Generates a dictionary with student progress
        status = check_class_status(assignment_list[0])

    else:
        assigned_on = None
        class_name = None
        progress = None
        status = 'inactive'

    

    # double-checks authorization before rendering template
    user_id = session['user_id']

    if user_id == task.created_by:
        return render_template("view_assignment.html", task=task, 
                                                       due_date=due_date, 
                                                       class_list=class_list, 
                                                       class_name=class_name,
                                                       assigned_on=assigned_on,
                                                       progress=progress,
                                                       status=status)
    else:
        flash("You do not have access to that page.")
        return redirect("/")


@app.route('/progress/<int:task_id>.json')
def check_for_student_progress(task_id):
    """Checks a list of assignments for a give task ID for recent changes and returns
    the updated assignments as JSON objects."""

    now = datetime.now()
    then = now - timedelta(seconds = 5)

    assignments_list = Assignment.query.filter(Assignment.task_id == task_id).all()

    updated = []

    for a in assignments_list:
        if a.viewed != None and a.viewed >= then:
            updated.append(a)

    task = Task.query.get(task_id)
    
    progress = report_student_progress(task, updated)

    if len(updated) > 0:
        return jsonify(progress)
    else:
        return "None"


@app.route('/teacher/<int:teacher_id>/assignments/<int:task_id>/edit', methods=["GET"])
def edit_assignment_form(teacher_id, task_id):
    """Shows assignment information in an editable form"""

    teacher = User.query.get(teacher_id)
    task = Task.query.get(task_id)

    #Unpack due_date into month, day, year, hour, minute, ampm
    month = task.due_date.strftime("%m")
    day = task.due_date.strftime("%d")
    year = task.due_date.strftime("%y")
    hour = task.due_date.strftime("%I")
    minute = task.due_date.strftime("%M")
    ampm = task.due_date.strftime("%p")

    if session.get('user_id') == teacher_id:
        return render_template("edit_assignment.html", teacher=teacher, 
                                                       task=task,
                                                       month=month,
                                                       day=day,
                                                       year=year,
                                                       hour=hour,
                                                       minute=minute,
                                                       ampm=ampm)
    else:
        flash("You do not have access to that page.")
        return redirect("/")


@app.route('/edit_assignment', methods=["POST"])
def edit_assignment():
    """Update the db with assignment edits from teacher"""

    # Get form variables
    title = request.form.get("title")
    goal = request.form.get("goal")
    directions = request.form.get("directions")
    link = request.form.get("link")
    month = request.form.get("month")
    day = request.form.get("day")
    year = request.form.get("year")
    hour = request.form.get("hour")
    minute = request.form.get("minute")
    ampm = request.form.get("ampm")
    teacher_id = int(request.form.get("teacher_id"))
    task_id = int(request.form.get("task_id"))

    date_string = "{}/{}/{} {}:{} {}".format(month, day, year, hour, minute, ampm)
    due_date = datetime.strptime(date_string, "%m/%d/%y %I:%M %p")

    task = Task.query.get(task_id)

    if teacher_id == task.created_by:

        task.title = title
        task.goal = goal
        task.directions = directions
        task.link = link
        task.due_date = due_date

        db.session.commit()
    
        flash("Your changes have been successfully saved!")
        return redirect('/teacher/{}/assignments/{}'.format(teacher_id, task_id))

    else:
        flash("You are not authorized to make this change.")
        return redirect("/")


@app.route('/assign', methods=["POST"])
def assign_to_class():
    """Assigns task to all users, students and teachers, associated with the selected class."""

    class_id = request.form.get("class-id")
    task_id = request.form.get("task_id")

    task = Task.query.get(task_id)
    this_class = Class.query.get(class_id)
    class_list = this_class.users
    task.assigned_to = class_id

    if session.get('user_id') == task.created_by:
        for user in class_list:
            new_assignment = Assignment(student_id=user.user_id,
                                        task_id=task_id,
                                        assigned=datetime.now())
            db.session.add(new_assignment)

        db.session.commit()

        flash("This has been successfully assigned to {}".format(this_class.class_name))
        return redirect("/teacher/{}/assignments/{}".format(task.created_by, task_id))
    
    else:
        flash("You are not authorized to make this change.")
        return redirect("/")


if __name__ == "__main__":
    # We have to set debug=True here, since it has to be True at the point
    # that we invoke the DebugToolbarExtension

    connect_to_db(app)

    # Use the DebugToolbar
    DebugToolbarExtension(app)

    app.config['DEBUG_TB_INTERCEPT_REDIRECTS'] = False

    DEBUG = "NO_DEBUG" not in os.environ
    PORT = int(os.environ.get("PORT", 5000))

    app.run(host="0.0.0.0", port=PORT, debug=DEBUG)