"""
MIT License

Copyright (c) 2022 Aʙɪsʜɴᴏɪ

Permission is hereby granted, free of charge, to any person obtaining a copy
of this software and associated documentation files (the "Software"), to deal
in the Software without restriction, including without limitation the rights
to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
copies of the Software, and to permit persons to whom the Software is
furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all
copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
SOFTWARE.
"""

import threading

from sqlalchemy import (
    BigInteger,
    Column,
    ForeignKey,
    String,
    UnicodeText,
    UniqueConstraint,
    func,
)

from Database.sql import BASE, SESSION
from Mikobot import dispatcher


class Users(BASE):
    __tablename__ = "users"
    user_id = Column(BigInteger, primary_key=True)
    username = Column(UnicodeText)

    def __init__(self, user_id, username=None):
        self.user_id = user_id
        self.username = username

    def __repr__(self):
        return "<ᴜsᴇʀ {} ({})>".format(self.username, self.user_id)


class Chats(BASE):
    __tablename__ = "chats"
    chat_id = Column(String(14), primary_key=True)
    chat_name = Column(UnicodeText, nullable=False)

    def __init__(self, chat_id, chat_name):
        self.chat_id = str(chat_id)
        self.chat_name = chat_name

    def __repr__(self):
        return "<ᴄʜᴀᴛ {} ({})>".format(self.chat_name, self.chat_id)


class ChatMembers(BASE):
    __tablename__ = "chat_members"
    priv_chat_id = Column(BigInteger, primary_key=True)
    # NOTE: Use dual primary key instead of private primary key?
    chat = Column(
        String(14),
        ForeignKey("chats.chat_id", onupdate="CASCADE", ondelete="CASCADE"),
        nullable=False,
    )
    user = Column(
        BigInteger,
        ForeignKey("users.user_id", onupdate="CASCADE", ondelete="CASCADE"),
        nullable=False,
    )
    __table_args__ = (UniqueConstraint("chat", "user", name="_chat_members_uc"),)

    def __init__(self, chat, user):
        self.chat = chat
        self.user = user

    def __repr__(self):
        return "<ᴄʜᴀᴛ ᴜsᴇʀ {} ({}) ɪɴ ᴄʜᴀᴛ {} ({})>".format(
            self.user.username,
            self.user.user_id,
            self.chat.chat_name,
            self.chat.chat_id,
        )


Users.__table__.create(checkfirst=True)
Chats.__table__.create(checkfirst=True)
ChatMembers.__table__.create(checkfirst=True)

INSERTION_LOCK = threading.RLock()


def ensure_bot_in_db():
    with INSERTION_LOCK:
        bot = Users(dispatcher.bot.id, dispatcher.bot.username)
        SESSION.merge(bot)
        SESSION.commit()


def update_user(user_id, username, chat_id=None, chat_name=None):
    with INSERTION_LOCK:
        user = SESSION.query(Users).get(user_id)
        if not user:
            user = Users(user_id, username)
            SESSION.add(user)
            SESSION.flush()
        else:
            user.username = username

        if not chat_id or not chat_name:
            SESSION.commit()
            return

        chat = SESSION.query(Chats).get(str(chat_id))
        if not chat:
            chat = Chats(str(chat_id), chat_name)
            SESSION.add(chat)
            SESSION.flush()

        else:
            chat.chat_name = chat_name

        member = (
            SESSION.query(ChatMembers)
            .filter(ChatMembers.chat == chat.chat_id, ChatMembers.user == user.user_id)
            .first()
        )
        if not member:
            chat_member = ChatMembers(chat.chat_id, user.user_id)
            SESSION.add(chat_member)

        SESSION.commit()


def get_userid_by_name(username):
    try:
        return (
            SESSION.query(Users)
            .filter(func.lower(Users.username) == username.lower())
            .all()
        )
    finally:
        SESSION.close()


def get_name_by_userid(user_id):
    try:
        return SESSION.query(Users).get(Users.user_id == int(user_id)).first()
    finally:
        SESSION.close()


def get_chat_members(chat_id):
    try:
        return SESSION.query(ChatMembers).filter(ChatMembers.chat == str(chat_id)).all()
    finally:
        SESSION.close()


def get_all_chats():
    try:
        return SESSION.query(Chats).all()
    finally:
        SESSION.close()


def get_all_users():
    try:
        return SESSION.query(Users).all()
    finally:
        SESSION.close()


def get_user_num_chats(user_id):
    try:
        return (
            SESSION.query(ChatMembers).filter(ChatMembers.user == int(user_id)).count()
        )
    finally:
        SESSION.close()


def get_user_com_chats(user_id):
    try:
        chat_members = (
            SESSION.query(ChatMembers).filter(ChatMembers.user == int(user_id)).all()
        )
        return [i.chat for i in chat_members]
    finally:
        SESSION.close()


def num_chats():
    try:
        return SESSION.query(Chats).count()
    finally:
        SESSION.close()


def num_users():
    try:
        return SESSION.query(Users).count()
    finally:
        SESSION.close()


def migrate_chat(old_chat_id, new_chat_id):
    with INSERTION_LOCK:
        chat = SESSION.query(Chats).get(str(old_chat_id))
        if chat:
            chat.chat_id = str(new_chat_id)
        SESSION.commit()

        chat_members = (
            SESSION.query(ChatMembers)
            .filter(ChatMembers.chat == str(old_chat_id))
            .all()
        )
        for member in chat_members:
            member.chat = str(new_chat_id)
        SESSION.commit()


ensure_bot_in_db()


def del_user(user_id):
    with INSERTION_LOCK:
        curr = SESSION.query(Users).get(user_id)
        if curr:
            SESSION.delete(curr)
            SESSION.commit()
            return True

        ChatMembers.query.filter(ChatMembers.user == user_id).delete()
        SESSION.commit()
        SESSION.close()
    return False


def rem_chat(chat_id):
    with INSERTION_LOCK:
        chat = SESSION.query(Chats).get(str(chat_id))
        if chat:
            SESSION.delete(chat)
            SESSION.commit()
        else:
            SESSION.close()