import enum

from sqlalchemy import Column, Integer, String, Text, DateTime, ForeignKey, Enum
from sqlalchemy.orm import relationship
from sqlalchemy.sql import func

from app.database import Base


class GroupMemberRole(str, enum.Enum):
    OWNER = "owner"
    ADMIN = "admin"
    MEMBER = "member"


class Group(Base):
    __tablename__ = "groups"

    id = Column(Integer, primary_key=True, index=True)
    name = Column(String(255), nullable=False)
    description = Column(Text, nullable=True)
    owner_id = Column(Integer, ForeignKey("users.id", ondelete="CASCADE"), 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())

    owner = relationship("User", back_populates="owned_groups")
    members = relationship(
        "GroupMember",
        back_populates="group",
        cascade="all, delete-orphan",
        order_by="GroupMember.joined_at",
    )


class GroupMember(Base):
    __tablename__ = "group_members"

    group_id = Column(
        Integer,
        ForeignKey("groups.id", ondelete="CASCADE"),
        primary_key=True,
    )
    user_id = Column(
        Integer,
        ForeignKey("users.id", ondelete="CASCADE"),
        primary_key=True,
    )
    role = Column(
        Enum(GroupMemberRole, name="group_member_role", create_type=False),
        nullable=False,
        default=GroupMemberRole.MEMBER,
    )
    joined_at = Column(DateTime(timezone=True), server_default=func.now())

    group = relationship("Group", back_populates="members")
    user = relationship("User", back_populates="group_memberships")