-- 回退:UNIQUE(user_id,uuid) → 全局 UNIQUE(uuid),platform CHECK 去掉 linux。
-- 有损:同一 uuid 跨用户的重复行只保留最早一行(id 最小),linux 平台行删除
-- (旧 CHECK 不接受)。次序与 up 相同(rename → 重建 → 复制 → drop)。

ALTER TABLE devices RENAME TO devices_old;

CREATE TABLE devices (
  id                 INTEGER PRIMARY KEY AUTOINCREMENT,
  uuid               TEXT NOT NULL UNIQUE,
  user_id            INTEGER NOT NULL,
  name               TEXT NOT NULL,
  platform           TEXT NOT NULL CHECK (platform IN ('ios','android','windows','macos')),
  last_seen          DATETIME NULL,
  created_at         DATETIME NOT NULL DEFAULT CURRENT_TIMESTAMP,
  client_version     TEXT NULL,
  totp_trusted_until DATETIME NULL,
  dp_uuid            TEXT NULL,
  FOREIGN KEY (user_id) REFERENCES users(id)
);

INSERT INTO devices (id, uuid, user_id, name, platform, last_seen, created_at,
                     client_version, totp_trusted_until, dp_uuid)
SELECT id, uuid, user_id, name, platform, last_seen, created_at,
       client_version, totp_trusted_until, dp_uuid
FROM devices_old o
WHERE o.platform IN ('ios','android','windows','macos')
  AND o.id = (SELECT MIN(i.id) FROM devices_old i WHERE i.uuid = o.uuid);

ALTER TABLE sessions RENAME TO sessions_old;

CREATE TABLE sessions (
  id             INTEGER PRIMARY KEY AUTOINCREMENT,
  user_id        INTEGER NOT NULL,
  device_id      INTEGER NOT NULL,
  refresh_jti    TEXT NOT NULL UNIQUE,
  client_ip      TEXT NULL,
  client_version TEXT NULL,
  created_at     DATETIME NOT NULL,
  last_active    DATETIME NULL,
  revoked_at     DATETIME NULL,
  FOREIGN KEY (user_id) REFERENCES users(id) ON DELETE CASCADE,
  FOREIGN KEY (device_id) REFERENCES devices(id) ON DELETE CASCADE
);

-- 只回填仍存在对应设备行的会话(被去重删掉的设备,其会话一并丢弃)。
INSERT INTO sessions (id, user_id, device_id, refresh_jti, client_ip, client_version,
                      created_at, last_active, revoked_at)
SELECT s.id, s.user_id, s.device_id, s.refresh_jti, s.client_ip, s.client_version,
       s.created_at, s.last_active, s.revoked_at
FROM sessions_old s
WHERE EXISTS (SELECT 1 FROM devices d WHERE d.id = s.device_id);

DROP TABLE sessions_old;
DROP TABLE devices_old;

CREATE INDEX idx_devices_user ON devices (user_id);
CREATE UNIQUE INDEX idx_devices_dp_uuid ON devices (dp_uuid);
CREATE INDEX idx_sessions_user ON sessions (user_id);
CREATE INDEX idx_sessions_device ON sessions (device_id);