"""Update ``laptop_replacement`` Feishu approval external_code.

Revision ID: 183
Revises: 182
Create Date: 2026-05-19

NOTE (2026-05-20 alembic chain hotfix): PR #408 briefly renamed
this file's revision to ``183_laptop`` to disambiguate from
PR #406's also-revision-"183" office-held migration. PR #409 then
renumbered the office-held chain to 186/187/188 anchored on
``down_revision = "183"`` — i.e. expecting THIS file to remain
revision="183". The PR #408 rename + PR #409 renumber landed on
main in different commits and the residual mismatch left the
chain orphaned at line `186 → 183 (missing)`. This restores the
historical ``revision = "183"`` so the chain is linear again and
production's ``alembic_version='183'`` stays valid without manual
SQL fixup. PR #408's chain (now 189-191 after hotfix renumber)
anchors off ``188_backfill_asset_holder_kind``.

Why this exists
---------------
The Feishu 电脑更换 (laptop_replacement) approval definition was rebuilt
on the Feishu open-platform side with a new form layout (conditional
visibility on additional widgets, refreshed required-set). The new
definition lives under a fresh approval code; the old code keeps the
legacy schema and will diverge.

This migration repoints ``integration_approval_flows.external_code`` for
``flow_key='laptop_replacement'`` (on the primary chat_approval/feishu
integration) at the new UUID, and invalidates
``platform_settings['approval.asset_template_cache']`` so the next
``/api/v1/approval/asset/templates`` read refetches the schema from
Feishu instead of serving the stale parsed widgets that were cached
under the old code.

Idempotency
-----------
* The UPDATE is keyed by ``(integration_id, flow_key)`` via the
  existing unique constraint; re-running is a no-op.
* The cache delete is unconditional — the next list call repopulates
  it. Safe even if the row was already absent.
* If the laptop_replacement row doesn't exist (greenfield deploy where
  026/027 never seeded it because the legacy env var wasn't set), this
  migration is a no-op for the row UPDATE. The cache delete still
  runs harmlessly. Operators on a greenfield install will create the
  row via the admin Integrations UI with the new code directly.
"""
from __future__ import annotations

import sqlalchemy as sa

from alembic import op

revision = "183"
down_revision = "182"
branch_labels = None
depends_on = None


_FLOW_KEY = "laptop_replacement"
_OLD_CODE = "3DF39DB6-7F1D-4CCB-9121-C9C73A852246"
_NEW_CODE = "7694D6BE-7FEE-4E49-96B5-A106FC4623DD"
_CACHE_KEY = "approval.asset_template_cache"


def _table_exists(bind, name: str) -> bool:
    return bind.execute(
        sa.text(
            "SELECT 1 FROM information_schema.TABLES "
            "WHERE TABLE_SCHEMA = DATABASE() AND TABLE_NAME = :n LIMIT 1"
        ),
        {"n": name},
    ).scalar() is not None


def upgrade() -> None:
    bind = op.get_bind()
    if _table_exists(bind, "integration_approval_flows"):
        bind.execute(
            sa.text(
                "UPDATE integration_approval_flows "
                "SET external_code = :new_code "
                "WHERE flow_key = :flow_key "
                "AND external_code = :old_code"
            ),
            {
                "new_code": _NEW_CODE,
                "old_code": _OLD_CODE,
                "flow_key": _FLOW_KEY,
            },
        )
    if _table_exists(bind, "platform_settings"):
        bind.execute(
            sa.text("DELETE FROM platform_settings WHERE `key` = :k"),
            {"k": _CACHE_KEY},
        )


def downgrade() -> None:
    bind = op.get_bind()
    if _table_exists(bind, "integration_approval_flows"):
        bind.execute(
            sa.text(
                "UPDATE integration_approval_flows "
                "SET external_code = :old_code "
                "WHERE flow_key = :flow_key "
                "AND external_code = :new_code"
            ),
            {
                "new_code": _NEW_CODE,
                "old_code": _OLD_CODE,
                "flow_key": _FLOW_KEY,
            },
        )
    if _table_exists(bind, "platform_settings"):
        bind.execute(
            sa.text("DELETE FROM platform_settings WHERE `key` = :k"),
            {"k": _CACHE_KEY},
        )