from __future__ import annotations
from datetime import datetime
from sqlalchemy import DateTime, ForeignKey, Index, Integer, String, Text
from sqlalchemy.dialects.postgresql import ARRAY
from sqlalchemy.orm import Mapped, mapped_column
from .base import Base
from steward.core.ids import time_ordered_id


class Ticket(Base):
    """A known problem, open until someone resolves it: attached to hosts
    and to what it is about (a container, a monitor, a resource), or to
    nothing. Numbered, so a person can say "#12"."""
    __tablename__ = "tickets"

    id: Mapped[int] = mapped_column(Integer, primary_key=True, autoincrement=True)
    title: Mapped[str] = mapped_column(String(200), nullable=False)
    body: Mapped[str | None] = mapped_column(Text, nullable=True)
    # An area key of Settings → Timeline, as a timeline entry names one.
    area: Mapped[str] = mapped_column(String(32), nullable=False)
    hosts: Mapped[list[str]] = mapped_column(ARRAY(String(128)), nullable=False, default=list)
    # What it is about when that is not a host: an alert rule's resource, a
    # container ("<host>/<name>"), a monitor's name.
    subject: Mapped[str | None] = mapped_column(String(255), nullable=True)
    status: Mapped[str] = mapped_column(String(16), nullable=False, default="open")
    opened_at: Mapped[datetime] = mapped_column(DateTime(timezone=True), nullable=False)
    # A username, or "<user> via MCP"; the id is who may be named its author.
    opened_by: Mapped[str] = mapped_column(String(64), nullable=False)
    opened_by_id: Mapped[str | None] = mapped_column(String(36), nullable=True)
    resolved_at: Mapped[datetime | None] = mapped_column(DateTime(timezone=True), nullable=True)
    resolved_by: Mapped[str | None] = mapped_column(String(64), nullable=True)
    resolution: Mapped[str | None] = mapped_column(Text, nullable=True)
    updated_at: Mapped[datetime] = mapped_column(DateTime(timezone=True), nullable=False)

    __table_args__ = (
        Index("ix_tickets_status", "status", "updated_at"),
        Index("ix_tickets_hosts", "hosts", postgresql_using="gin"),
    )


class TicketLink(Base):
    """What a ticket is linked to: an alert rule or a metric anomaly, by id."""
    __tablename__ = "ticket_links"

    ticket_id: Mapped[int] = mapped_column(Integer, ForeignKey("tickets.id", ondelete="CASCADE"),
                                           primary_key=True)
    ref_type: Mapped[str] = mapped_column(String(32), primary_key=True)
    ref_id: Mapped[str] = mapped_column(String(64), primary_key=True)

    __table_args__ = (Index("ix_ticket_links_ref", "ref_type", "ref_id"),)


class TicketNote(Base):
    """One line of a ticket's log: a comment, or it being opened, edited,
    resolved or reopened."""
    __tablename__ = "ticket_notes"

    id: Mapped[str] = mapped_column(String(36), primary_key=True, default=time_ordered_id)
    ticket_id: Mapped[int] = mapped_column(Integer, ForeignKey("tickets.id", ondelete="CASCADE"),
                                           nullable=False)
    at: Mapped[datetime] = mapped_column(DateTime(timezone=True), nullable=False)
    # comment | opened | edited | resolved | reopened
    kind: Mapped[str] = mapped_column(String(16), nullable=False)
    actor: Mapped[str] = mapped_column(String(64), nullable=False)
    body: Mapped[str | None] = mapped_column(Text, nullable=True)

    __table_args__ = (Index("ix_ticket_notes_ticket", "ticket_id", "at"),)