from __future__ import annotations
import enum
from datetime import datetime
from typing import Optional
from sqlalchemy import ForeignKey, String, Enum, DateTime, func
from sqlalchemy.orm import Mapped, mapped_column
from app.db.session import Base

class PostType(str, enum.Enum):
    text = "text"
    photo = "photo"
    video = "video"
    animation = "animation"

class PostStatus(str, enum.Enum):
    draft = "draft"
    scheduled = "scheduled"
    sent = "sent"
    failed = "failed"

class Post(Base):
    __tablename__ = "posts"

    id: Mapped[int] = mapped_column(primary_key=True)
    owner_id: Mapped[int] = mapped_column(ForeignKey("users.id", ondelete="CASCADE"))
    bot_id: Mapped[Optional[int]] = mapped_column(ForeignKey("bots.id", ondelete="SET NULL"), nullable=True)
    channel_id: Mapped[int] = mapped_column(ForeignKey("channels.id", ondelete="CASCADE"))

    type: Mapped[PostType] = mapped_column()
    text: Mapped[str | None] = mapped_column(String(4096))
    media_file_id: Mapped[Optional[str]] = mapped_column(String(512))
    parse_mode: Mapped[Optional[str]] = mapped_column(String(16))
    keyboard_id: Mapped[Optional[int]] = mapped_column(ForeignKey("keyboards.id", ondelete="SET NULL"))

    status: Mapped[PostStatus] = mapped_column(Enum(PostStatus), default=PostStatus.draft)
    created_at: Mapped[datetime] = mapped_column(DateTime(timezone=True), server_default=func.now())
    sent_at: Mapped[Optional[datetime]] = mapped_column(DateTime(timezone=True), nullable=True)

class ScheduleStatus(str, enum.Enum):
    pending = "pending"
    done = "done"
    cancelled = "cancelled"

class Schedule(Base):
    __tablename__ = "schedules"

    id: Mapped[int] = mapped_column(primary_key=True)
    post_id: Mapped[int] = mapped_column(ForeignKey("posts.id", ondelete="CASCADE"))
    due_at: Mapped[datetime] = mapped_column(DateTime(timezone=True))
    timezone: Mapped[str] = mapped_column(String(64))
    celery_task_id: Mapped[Optional[str]] = mapped_column(String(128))
    status: Mapped[ScheduleStatus] = mapped_column(Enum(ScheduleStatus), default=ScheduleStatus.pending)