"""微信 clawbot 改成"扫码登录 + 长轮询"

Revision ID: 0013
Revises: 0012
Create Date: 2026-11-05

上一版（0012）做成了"clawbot 往我们这 POST webhook"。真实协议是腾讯 iLink Bot：
我们先扫码登录拿 `bot_token`，再由我们长轮询 `getupdates` 拉消息（见
`app/services/wechat_ilink.py` 文件头的出处说明）。所以这张表要补登录态与游标：

- `bot_token_enc`：加密后的登录态（密钥由 JWT_SECRET 派生），换 secret 就要重新扫码；
- `ilink_user_id`：扫码的微信号，界面上显示"谁扫的"；
- `base_url`：服务端可能下发新基址；
- `sync_buf`：长轮询游标，丢了会重复收消息；
- `context_token`：回复必须带对方上一条消息的 context_token。

`bot_channel.status` 增加 `pending`（等扫码）与 `expired`（登录态失效）两个取值；
`token_hash` 是上一版遗留列，改成可空、不再使用。
"""

from __future__ import annotations

from collections.abc import Sequence

from alembic import op

from app.roles import APP_ROLE

revision: str = "0013"
down_revision: str = "0012"
branch_labels: Sequence[str] | None = None
depends_on: Sequence[str] | None = None

STATEMENTS = (
    "ALTER TABLE bot_channel ADD COLUMN IF NOT EXISTS bot_token_enc text",
    "ALTER TABLE bot_channel ADD COLUMN IF NOT EXISTS ilink_user_id varchar(64)",
    "ALTER TABLE bot_channel ADD COLUMN IF NOT EXISTS base_url text",
    "ALTER TABLE bot_channel ADD COLUMN IF NOT EXISTS sync_buf text",
    "ALTER TABLE bot_channel ADD COLUMN IF NOT EXISTS context_token text",
    "ALTER TABLE bot_channel ALTER COLUMN token_hash DROP NOT NULL",
    "ALTER TABLE bot_channel ALTER COLUMN status SET DEFAULT 'pending'",
    "COMMENT ON COLUMN bot_channel.bot_token_enc IS 'iLink 登录态，Fernet 加密（密钥由 JWT_SECRET 派生）'",
    "COMMENT ON COLUMN bot_channel.sync_buf IS 'getupdates 游标，丢了会重复收消息'",
    f"GRANT SELECT, INSERT, UPDATE, DELETE ON bot_channel TO {APP_ROLE}",
)

DOWN_STATEMENTS = (
    "ALTER TABLE bot_channel DROP COLUMN IF EXISTS context_token",
    "ALTER TABLE bot_channel DROP COLUMN IF EXISTS sync_buf",
    "ALTER TABLE bot_channel DROP COLUMN IF EXISTS base_url",
    "ALTER TABLE bot_channel DROP COLUMN IF EXISTS ilink_user_id",
    "ALTER TABLE bot_channel DROP COLUMN IF EXISTS bot_token_enc",
)


def upgrade() -> None:
    for statement in STATEMENTS:
        op.execute(statement)


def downgrade() -> None:
    for statement in DOWN_STATEMENTS:
        op.execute(statement)