from sqlalchemy import Column, String, Integer, DateTime, ForeignKey, func
from sqlalchemy.orm import relationship
from database import Base


class Post(Base):
    __tablename__ = "posts"

    id = Column(String, primary_key=True, index=True)
    username = Column(String, nullable=False)
    content = Column(String, nullable=False)
    created_at = Column(DateTime(timezone=True), server_default=func.now())
    updated_at = Column(DateTime(timezone=True), server_default=func.now(), onupdate=func.now())
    
    comments = relationship("Comment", back_populates="post", cascade="all, delete-orphan")
    likes = relationship("Like", back_populates="post", cascade="all, delete-orphan")


class Comment(Base):
    __tablename__ = "comments"

    id = Column(String, primary_key=True, index=True)
    post_id = Column(String, ForeignKey("posts.id", ondelete="CASCADE"), nullable=False)
    username = Column(String, nullable=False)
    content = Column(String, nullable=False)
    created_at = Column(DateTime(timezone=True), server_default=func.now())
    updated_at = Column(DateTime(timezone=True), server_default=func.now(), onupdate=func.now())
    
    post = relationship("Post", back_populates="comments")


class Like(Base):
    __tablename__ = "likes"

    post_id = Column(String, ForeignKey("posts.id", ondelete="CASCADE"), primary_key=True)
    username = Column(String, primary_key=True)
    created_at = Column(DateTime(timezone=True), server_default=func.now())
    
    post = relationship("Post", back_populates="likes")