"""Durable notification provider-delivery claims.

Revision ID: 443
Revises: 442
Create Date: 2026-08-02

#2408: commit a lease and stable provider keys before non-transactional
Feishu/SMTP I/O.  A stale lease becomes an explicit uncertain outcome instead
of entering the automatic retry pool and possibly sending a duplicate.
"""
from __future__ import annotations

import sqlalchemy as sa

from alembic import op
from app.core.sql_types import GUID

revision = "443"
down_revision = "442"
branch_labels = None
depends_on = None


def upgrade() -> None:
    op.alter_column(
        "notification_outbox",
        "status",
        existing_type=sa.String(16),
        type_=sa.String(24),
        existing_nullable=False,
        existing_server_default="pending",
    )
    op.add_column(
        "notification_outbox",
        sa.Column("delivery_claim_token", GUID(), nullable=True),
    )
    op.add_column(
        "notification_outbox",
        sa.Column("delivery_claimed_at", sa.DateTime(timezone=True), nullable=True),
    )
    op.add_column(
        "notification_outbox",
        sa.Column(
            "delivery_lease_expires_at",
            sa.DateTime(timezone=True),
            nullable=True,
        ),
    )
    op.add_column(
        "notification_outbox",
        sa.Column("delivery_claimed_channels", sa.JSON(), nullable=True),
    )
    op.add_column(
        "notification_outbox",
        sa.Column(
            "delivery_claim_count",
            sa.Integer(),
            nullable=False,
            server_default="0",
        ),
    )
    op.add_column(
        "notification_outbox",
        sa.Column("provider_delivery_keys", sa.JSON(), nullable=True),
    )
    op.create_index(
        "ix_notification_outbox_delivery_lease",
        "notification_outbox",
        ["status", "delivery_lease_expires_at"],
    )


def downgrade() -> None:
    # The old VARCHAR(16) cannot represent ``delivery_uncertain``. Preserve
    # safety on rollback: live claims re-enter retry, uncertain outcomes
    # become dead letters (never an automatic duplicate).
    op.execute(
        "UPDATE notification_outbox SET status = 'failed' "
        "WHERE status = 'delivering'"
    )
    op.execute(
        "UPDATE notification_outbox "
        "SET status = 'dead', last_error = CONCAT("
        "'migration 443 rollback: delivery outcome remained uncertain | ', "
        "COALESCE(last_error, '')) "
        "WHERE status = 'delivery_uncertain'"
    )
    op.drop_index(
        "ix_notification_outbox_delivery_lease",
        table_name="notification_outbox",
    )
    op.drop_column("notification_outbox", "provider_delivery_keys")
    op.drop_column("notification_outbox", "delivery_claim_count")
    op.drop_column("notification_outbox", "delivery_claimed_channels")
    op.drop_column("notification_outbox", "delivery_lease_expires_at")
    op.drop_column("notification_outbox", "delivery_claimed_at")
    op.drop_column("notification_outbox", "delivery_claim_token")
    op.alter_column(
        "notification_outbox",
        "status",
        existing_type=sa.String(24),
        type_=sa.String(16),
        existing_nullable=False,
        existing_server_default="pending",
    )