from datetime import datetime
from typing import Optional

from sqlalchemy import func, ForeignKey, DateTime
from sqlalchemy.orm import mapped_column, Mapped, relationship

from app.database import Base


class Chats(Base):
    __tablename__ = "chats"

    id: Mapped[int] = mapped_column(primary_key=True)
    chat_for = mapped_column(ForeignKey("users.id"))
    chat_name: Mapped[str]
    visibility: Mapped[bool] = mapped_column(server_default='true')
    created_by: Mapped[int] = mapped_column(ForeignKey("users.id"))

    message = relationship("Messages", back_populates="chat")
    usersxchats = relationship("UsersXChats", back_populates="chat")
    user_to_exclude = relationship("Users", primaryjoin='Chats.chat_for == Users.id', back_populates="chat")
    user_who_create = relationship("Users", primaryjoin='Chats.created_by == Users.id', back_populates="creator")

    def __str__(self):
        return f"Чат #{self.id}. Виден: {self.visibility}. Сделан {self.created_by}"


class Messages(Base):
    __tablename__ = "messages"

    id: Mapped[int] = mapped_column(primary_key=True)
    chat_id = mapped_column(ForeignKey("chats.id"))
    user_id = mapped_column(ForeignKey("users.id"))
    message: Mapped[Optional[str]]
    image_url: Mapped[Optional[str]]
    created_at: Mapped[datetime] = mapped_column(DateTime(timezone=True), server_default=func.now())
    visibility: Mapped[bool] = mapped_column(server_default='true')

    chat = relationship("Chats", back_populates="message")
    user = relationship("Users", back_populates="message")

    def __str__(self):
        return f"#{self.id} {self.message} от {self.user_id}. Написано {self.created_at}"


class UsersXChats(Base):
    __tablename__ = "usersxchats"

    id: Mapped[int] = mapped_column(primary_key=True)
    user_id = mapped_column(ForeignKey("users.id"))
    chat_id = mapped_column(ForeignKey("chats.id"))

    chat = relationship("Chats", back_populates="usersxchats")
    user = relationship("Users", back_populates="usersxchats")

    def __str__(self):
        return f"Юзер #{self.user_id} допущен к чату {self.chat_id}"