"""Create event_outbox table for transactional outbox pattern.

Revision ID: 0040_outbox
Revises: 0039_contact_normalize
Create Date: 2026-07-25

Stores domain events in a durable table so they survive process crashes,
restarts, and multi-replica deployments.  A background worker polls the
outbox and publishes events to the in-process event bus.
"""

from __future__ import annotations

from typing import Union

import sqlalchemy as sa
from alembic import op

# revision identifiers
revision: str = "0040_outbox"
down_revision: Union[str, None] = "0039_contact_normalize"
branch_labels: Union[str, None] = None
depends_on: Union[str, None] = None


def upgrade() -> None:
    conn = op.get_bind()

    # Ensure pgcrypto extension for gen_random_uuid()
    conn.execute(sa.text("CREATE EXTENSION IF NOT EXISTS pgcrypto"))

    conn.execute(
        sa.text(
            """
            CREATE TABLE IF NOT EXISTS event_outbox (
                id              UUID PRIMARY KEY DEFAULT gen_random_uuid(),
                tenant_id       UUID NOT NULL,
                event_name      VARCHAR(255) NOT NULL,
                payload         JSONB NOT NULL,
                status          VARCHAR(20) NOT NULL DEFAULT 'pending',
                attempts        INT NOT NULL DEFAULT 0,
                max_attempts    INT NOT NULL DEFAULT 5,
                next_retry_at   TIMESTAMPTZ,
                created_at      TIMESTAMPTZ NOT NULL DEFAULT now(),
                updated_at      TIMESTAMPTZ NOT NULL DEFAULT now(),
                published_at    TIMESTAMPTZ
            )
            """
        )
    )

    # Index for the worker query: WHERE status = 'pending' ORDER BY next_retry_at
    conn.execute(
        sa.text(
            "CREATE INDEX IF NOT EXISTS ix_outbox_status "
            "ON event_outbox (status, next_retry_at)"
        )
    )
    conn.execute(
        sa.text(
            "CREATE INDEX IF NOT EXISTS ix_outbox_tenant "
            "ON event_outbox (tenant_id)"
        )
    )


def downgrade() -> None:
    conn = op.get_bind()
    conn.execute(sa.text("DROP INDEX IF EXISTS ix_outbox_tenant"))
    conn.execute(sa.text("DROP INDEX IF EXISTS ix_outbox_status"))
    conn.execute(sa.text("DROP TABLE IF EXISTS event_outbox"))