"""

@Author: Aseem Jain

@profile: https://www.linkedin.com/in/premaseem/

We will be designing a system with the following requirements:

Any non-member (guest) can search and view questions. However, to add or upvote a question, they have to become a member.

Members should be able to post new questions.

Members should be able to add an answer to an open question.

Members can add comments to any question or answer.

A member can upvote a question, answer or comment.

Members can flag a question, answer or comment, for serious problems or moderator attention.

Any member can add a bounty to their question to draw attention.

Members will earn badges for being helpful.

Members can vote to close a question; Moderators can close or reopen any question.

Members can add tags to their questions. A tag is a word or phrase that describes the topic of the question.

Members can vote to delete extremely off-topic or very low-quality questions.

Moderators can close a question or undelete an already deleted question.

The system should also be able to identify most frequently used tags in the questions.

We have five main actors in our system:

Admin: Mainly responsible for blocking or unblocking members.

Guest: All guests can search and view questions.

Member: Members can perform all activities that guests can, in addition to which they can add/remove questions, answers, and comments. Members can delete and un-delete their questions, answers or comments.

Moderator: In addition to all the activities that members can perform, moderators can close/delete/undelete any question.

System: Mainly responsible for sending notifications and assigning badges to members.

Here are the top use cases for Stack Overflow:

Top User Cases:

Search questions.

Create a new question with bounty and tags.

Add/modify answers to questions.

Add comments to questions or answers.

Moderators can close, delete, and un-delete any question.

"""

from datetime import datetime

from enum import Enum

class QuestionStatus(Enum):

OPEN, CLOSED, ON_HOLD, DELETED = 1, 2, 3, 4

class QuestionClosingRemark(Enum):

DUPLICATE, OFF_TOPIC, TOO_BROAD, NOT_CONSTRUCTIVE, NOT_A_REAL_QUESTION, PRIMARILY_OPINION_BASED = 1, 2, 3, 4, 5, 6

class AccountStatus(Enum):

ACTIVE, CLOSED, CANCELED, BLACKLISTED, BLOCKED = 1, 2, 3, 4, 5

# For simplicity, we are not defining getter and setter functions. The reader can

# assume that all class attributes are private and accessed through their respective

# public getter methods and modified only through their public methods function.

class Account:

def __init__(self, id, password, name, address, email, phone, status=AccountStatus.Active):

self.__id = id

self.__password = password

self.__name = name

self.__address = address

self.__email = email

self.__phone = phone

self.__status = status

self.__reputation = 0

def reset_password(self):

None

class Member:

def __init__(self, account):

self.__account = account

self.__badges = []

def get_reputation(self):

return self.__account.get_reputation()

def get_email(self):

return self.__account.get_email()

def create_question(self, question):

None

def create_tag(self, tag):

None

class Admin(Member):

def block_member(self, member):

None

def unblock_member(self, member):

None

class Moderator(Member):

def close_question(self, question):

None

def undelete_question(self, question):

None

class Badge:

def __init__(self, name, description):

self.__name = name

self.__description = description

class Tag:

def __init__(self, name, description):

self.__name = name

self.__description = description

self.__daily_asked_frequency = 0

self.__weekly_asked_frequency = 0

# import datetime

class Notification:

def __init__(self, id, content):

self.__notification_id = id

self.__created_on = datetime.datetime.now()

self.__content = content

def send_notification(self):

None

import datetime

class Photo:

def __init__(self, id, path, member):

self.__photo_id = id

self.__photo_path = path

self.__creation_date = datetime.datetime.now()

self.__creating_member = member

def delete(self):

None

# import datetime

class Bounty:

def __init__(self, reputation, expiry):

self.__reputation = reputation

self.__expiry = expiry

def modify_reputation(self, reputation):

None

from abc import ABC, abstractmethod

class Search(ABC):

def search(self, query):

None

import datetime

class Question(Search):

def __init__(self, title, description, bounty, asking_member):

self.__title = title

self.__description = description

self.__view_count = 0

self.__vote_count = 0

self.__creation_time = datetime.datetime.now()

self.__update_time = datetime.datetime.now()

self.__status = QuestionStatus.OPEN

self.__closing_remark = QuestionClosingRemark.DUPLICATE

self.__bounty = bounty

self.__asking_member = asking_member

self.__photos = []

self.__comments = []

self.__answers = []

def close(self):

None

def undelete(self):

None

def add_comment(self, comment):

None

def add_bounty(self, bounty):

None

def search(self, query):

# return all questions containing the string query in their title or description.

None

class Comment:

def __init__(self, text, member):

self.__text = text

self.__creation_time = datetime.datetime.now()

self.__flag_count = 0

self.__vote_count = 0

self.__asking_member = member

def increment_vote_count(self):

None

class Answer:

def __init__(self, text, member):

self.__answer_text = text

self.__accepted = False

self.__vote_count = 0

self.__flag_count = 0

self.__creation_time = datetime.datetime.now()

self.__creating_member = member

self.__photos = []

def increment_vote_count(self):

None