【数据存储】数据修复：误操作的角色状态回档

---角色状态快照：每小时一版，留 7 天
setontimerex(63, 3600)
function Repair.snapshot()
    local ids = Repair.activeRoleIds()
    for _, id in ipairs(ids) do
        local snap = {
            bag = Bag.serialize(id),
            vars = Vars.serialize(id),
            at = os.time(),
        }
        DB.exec("INSERT INTO role_snapshots SET ?", snap)
    end
    Repair.purge(7 * 86400)
end

---单角色回档：指定维度切回快照
function Repair.rollback(userId, dims, snapAt)
    local snap = DB.queryRow(
        "SELECT * FROM role_snapshots WHERE uid = ? AND at <= ? " ..
        "ORDER BY at DESC LIMIT 1", userId, snapAt)
    if not snap then return false, "无可用快照" end
    DB.trans(function()
        if dims.bag then Bag.restore(userId, snap.bag) end
        if dims.vars then Vars.restore(userId, snap.vars) end
        Repair.mark(userId, dims, snapAt)
    end)
    Mail.send(userId, 8003, "数据修复完成",
        "您的数据已恢复至 " .. os.date("%m-%d %H:%M", snapAt), "")
    return true
end