from datetime import datetime, timezone
from enum import Enum

from sqlalchemy import Boolean, DateTime, Enum as SqlEnum, ForeignKey, Integer, String, Text
from sqlalchemy.orm import Mapped, mapped_column, relationship

from .database import Base


class UserRole(str, Enum):
    """Роли пользователей панели."""

    admin = "admin"
    client = "client"


class GuestType(str, Enum):
    """Тип виртуализированной системы."""

    vm = "vm"
    lxc = "lxc"


class InstanceStatus(str, Enum):
    """Состояние инстанса в панели."""

    creating = "creating"
    running = "running"
    stopped = "stopped"
    error = "error"
    deleting = "deleting"
    deleted = "deleted"


class User(Base):
    """Пользователь панели с Argon2id-хешем пароля."""

    __tablename__ = "users"

    id: Mapped[int] = mapped_column(Integer, primary_key=True)
    email: Mapped[str] = mapped_column(String(320), unique=True, index=True)
    password_hash: Mapped[str] = mapped_column(String(512))
    role: Mapped[UserRole] = mapped_column(
        SqlEnum(UserRole), default=UserRole.client, nullable=False
    )
    is_active: Mapped[bool] = mapped_column(Boolean, default=True, nullable=False)
    created_at: Mapped[datetime] = mapped_column(
        DateTime(timezone=True),
        default=lambda: datetime.now(timezone.utc),
        nullable=False,
    )
    instances: Mapped[list["Instance"]] = relationship(back_populates="owner")


class Template(Base):
    """Тарифный шаблон VM или LXC, доступный клиентам."""

    __tablename__ = "templates"

    id: Mapped[int] = mapped_column(Integer, primary_key=True)
    name: Mapped[str] = mapped_column(String(64), unique=True, index=True)
    description: Mapped[str] = mapped_column(Text, default="")
    guest_type: Mapped[GuestType] = mapped_column(SqlEnum(GuestType), nullable=False)
    source_vmid: Mapped[int | None] = mapped_column(Integer, nullable=True)
    source_template: Mapped[str | None] = mapped_column(String(512), nullable=True)
    cores: Mapped[int] = mapped_column(Integer, default=1, nullable=False)
    memory_mb: Mapped[int] = mapped_column(Integer, default=1024, nullable=False)
    disk_gb: Mapped[int] = mapped_column(Integer, default=10, nullable=False)
    is_active: Mapped[bool] = mapped_column(Boolean, default=True, nullable=False)
    created_at: Mapped[datetime] = mapped_column(
        DateTime(timezone=True),
        default=lambda: datetime.now(timezone.utc),
        nullable=False,
    )
    instances: Mapped[list["Instance"]] = relationship(back_populates="template")


class Instance(Base):
    """Инстанс VM/LXC, принадлежащий пользователю."""

    __tablename__ = "instances"

    id: Mapped[int] = mapped_column(Integer, primary_key=True)
    name: Mapped[str] = mapped_column(String(63))
    vmid: Mapped[int | None] = mapped_column(Integer, unique=True, nullable=True)
    node: Mapped[str] = mapped_column(String(64))
    guest_type: Mapped[GuestType] = mapped_column(SqlEnum(GuestType), nullable=False)
    status: Mapped[InstanceStatus] = mapped_column(
        SqlEnum(InstanceStatus), default=InstanceStatus.creating, nullable=False
    )
    owner_id: Mapped[int] = mapped_column(ForeignKey("users.id"), index=True)
    template_id: Mapped[int] = mapped_column(ForeignKey("templates.id"), index=True)
    created_at: Mapped[datetime] = mapped_column(
        DateTime(timezone=True),
        default=lambda: datetime.now(timezone.utc),
        nullable=False,
    )
    owner: Mapped[User] = relationship(back_populates="instances")
    template: Mapped[Template] = relationship(back_populates="instances")