"""Add google_calendar to channel_type CHECK constraint

Revision ID: 013
Revises: 012
Create Date: 2026-03-26

Adds 'google_calendar' to the valid channel types in channel_connections.
This enables per-tenant Google Calendar OAuth token storage alongside
existing Slack/WhatsApp/web connections.

Steps:
  1. Drop old CHECK constraint on channel_connections.channel_type
  2. Re-create it with the updated list including 'google_calendar'
"""

from __future__ import annotations

from alembic import op

# Alembic revision identifiers
revision: str = "013"
down_revision: str | None = "012"
branch_labels = None
depends_on = None

# All valid channel types including 'google_calendar'
_CHANNEL_TYPES = (
    "slack", "whatsapp", "mattermost", "rocketchat", "teams", "telegram", "signal", "web", "google_calendar"
)


def upgrade() -> None:
    # Drop the existing CHECK constraint (added in 008_web_chat.py as chk_channel_type)
    op.execute("ALTER TABLE channel_connections DROP CONSTRAINT IF EXISTS chk_channel_type")

    # Re-create with the updated list
    op.execute(
        "ALTER TABLE channel_connections ADD CONSTRAINT chk_channel_type "
        f"CHECK (channel_type IN {tuple(_CHANNEL_TYPES)})"
    )


def downgrade() -> None:
    # Restore 008's constraint (without google_calendar)
    _PREV_TYPES = (
        "slack", "whatsapp", "mattermost", "rocketchat", "teams", "telegram", "signal", "web"
    )
    op.execute("ALTER TABLE channel_connections DROP CONSTRAINT IF EXISTS chk_channel_type")
    op.execute(
        "ALTER TABLE channel_connections ADD CONSTRAINT chk_channel_type "
        f"CHECK (channel_type IN {tuple(_PREV_TYPES)})"
    )