pseudocode.txt

############
## app.py ##
############

# Decorator function that takes a function f as an argument
def login_required(f):
    # Inner function that accepts any number of positional and keyword arguments (*args, **kwargs)
    def wrap(*args, **kwargs):
        if 'username' not in session:
            redirect to /login route
        call the original function f with the provided arguments
    wrap.__name__ = f.__name__
    return wrap


# Route for user signup
@app.route('/signup', methods=['POST'])
def doSignup():
    try:
        user_data = dictionary containing signup form data (with hashed password)

        if username, email, or password are empty:
            return an error message and status code 400

        # Check if user already exists
        if a user with the enetered username already exists:
            return an error message and status code 409

        # Add the new user to the database
        users.add_user(user_data)
        user = users.find_user_by_username(user_data['username'])
        add username and user.student_id to session
        add next_semester_id to session by calling the courses.get_next_semester() function
        redirect to root route

    # Handle specific database errors
    except mysql.connector.Error as db_err:
        return an error message and status code 500
    
    # Handle missing data in the request JSON
    except KeyError as key_err:
        return an error message and status code 400
    
    # Catch all other exceptions
    except Exception as ex:
        return an error message and status code 500


# Route for user login
@app.route('/login', methods=['POST'])
def doLogin():
    try:
        get username and password from post form data

        if username or password are empty:
            return an error message and status code 400

        # Find the user by username
        user = users.find_user_by_username(username)
        if user not found:
            return an error message and status code 404

        # Check the password
        get hashed password from the found user
        if the entered password (after being hashed) matches t he hashed password from the user:
            add username and user.student_id to session
            add next_semester_id to session by calling the courses.get_next_semester() function
            redirect to root route
        else:
            return an error message and status code 401

    # Handle specific database errors
    except mysql.connector.Error as db_err:
        return an error message and status code 500

    # Handle missing data in the request JSON
    except KeyError as key_err:
        return an error message and status code 400

    # Catch all other exceptions
    except Exception as ex:
        return an error message and status code 500


@app.route('/login', methods=['GET'])
def login():
    if 'username' in session:
        redirect to root route
    render the 'login.html' template


@app.route('/signup', methods=['GET'])
def signup():
    if 'username' in session:
        redirect to root route
    render the 'signup.html' template


@app.route('/')
@login_required
def home():
    registered_courses = courses.get_registered_courses(session['next_semester_id'], session['student_id'])
    render the 'registered_courses.html' template, passing the course data so it can be displayed in the UI


@app.route('/course_search')
@login_required
def course_search():
    render the 'course_search.html'


@app.route('/get_completed_credits')
@login_required
def get_completed_credits():
    completed_credits = courses.get_completed_credits(session['next_semester_id'], session['student_id'])
    return the student's completed credits for each course type in json format


@app.route('/search_courses')
@login_required
def search_courses():
    course_type = request.args.get('course_type')
    return courses.search_courses(session['next_semester_id'], session['student_id'], course_type)


@app.route('/register_for_course', methods=['POST'])
@login_required
def register_for_course():
    course_id = 'course_id' value from form data
    return courses.register_for_course(session['next_semester_id'], session['student_id'], course_id)


@app.route('/drop_course', methods=['POST'])
@login_required
def drop_course():
    course_id = 'course_id' value from form data
    return courses.drop_course(session['next_semester_id'], session['student_id'], course_id)


@app.route('/profile')
@login_required
def profile():
    user = users.find_user_by_username(session['username'])
    render the 'profile.html' template, passing the user data so it can be displayed in the UI


@app.route('/logout', methods=['POST'])
@login_required
def logout():
    # Check if user is logged in (already checked by @login_required, but just for safe measure to avoid any errors)
    if 'username' in session and 'student_id' in session and 'next_semester_id' in session:
        remove username, student_id and next_semester_id from session
        redirect '/login' route
    else:
        return error message and status code 401


##############
## users.py ##
##############

# Check if user exists
def user_exists(username):
    connect to database
    user = query to see if the user exists in the student table based on username
    close the database connection
    return user is not None

# Add a new user
def add_user(data):
    connect to database
    try:
        insert a new record into the students table with the user info from the signup form
    except mysql.connector.Error as db_err:
        return an error message
    finally:
        close the database connection
    return "Success!"


# Find a user by username
def find_user_by_username(username):
    connect to database
    user = query the user's info from the student table based on username
    close the connection
    return user


################
## courses.py ##
################

# get list of registered courses
def get_next_semester():
    connect to database
    semester = query the next semester's data from the semesters table
    close the database connection
    return the semester's id


# get list of registered courses
def get_registered_courses(semester_id, student_id):
    connect to database
    courses = query the courses the student has registered for for the next semester
    close the database connection
    return courses


# get all completed credits, broken down by course type
def get_completed_credits(next_semester_id, student_id):
    connect to database
    courses = query the courses the student has passed, or is currently taking, or is registered to take next semester
    close the database connection
    return courses


# get list of courses the student can sign up for
def search_courses(semester_id, student_id, course_type):
    connect to database
    courses = query all courses of a specific course type that fall under the student's major, aren't already in the student's registered class list, and aren't full
    close the database connection
    return courses


# register for a single course
def register_for_course(semester_id, student_id, course_id):
    try:
      connect to database
      insert a new record into the student_courses table with the student_id, course_id and semester_id
    except mysql.connector.Error as db_err:
        return an error message
    finally:
        close the database connection
    return "Success!"


# drop a single course
def drop_course(semester_id, student_id, course_id):
    try:
      connect to database
      delete the record from the student_courses table with the corresponding student_id, course_id and semester_id
    except mysql.connector.Error as db_err:
        return an error message
    finally:
        close the database connection
    return "Success!"


###########
## db.py ##
###########

# Database configuration using environment variables
db_config = dictionary with database configuration variables

# Connect to the database
def get_db_connection():
    try:
        connection = create database connection
        return connection
    except Error as err:
        if the error is an access denied error:
            print("Something is wrong with your user name or password")
        elif the error involves the database not existing:
            print("Database does not exist")
        else:
            print(err)