i think the problem of this function you got too many arguments, better to avoid it

For side buy, you don't need Base asset balance, you only need Quote asset balance and the buy price to calculate the actual quantity.

For side sell, you only need Base asset balance, quote balance and price are not used for this case

I want to have a unified way to check the balance when submitting an order with SubmitOrder.
Maybe it will be better if I pass SubmitOrder instead.

Updated function signature:

func HasSufficientBalance(
	tradingMarket types.Market,
	submitOrder types.SubmitOrder,
	balances types.BalanceMap,
) (bool, error)

If our goal is to place an order no matter what—or at least as reliably as possible—we shouldn’t just return an error.
I think this is actually by design, so we need to consider the real-world scenario.

I'm not thinking about a guarantee on placing order.
Instead, I'd like to leave it to the caller to decide what to do next if there is an error concerning the balances.
That's why I return an error here.

why?

I think the issue lies in the need for a thread-safe way to access position-related information,
which is used to determine trading conditions.

Perhaps, just like we discussed offline,
renaming it to "snapshot" would make it easier to understand.

I leave the core API unchanged and move the locking util function to a private module in xgap folder instead.

maybe return type error? and use fmt.Errorf() for the error message

ok

HasSufficientBalance sounds you will return bool, but it returns error

Fixed

you are generating an new order, not returning an existing order, so using prefix "get" could be confusing

you may use "build" or "new" as the prefix

done.

pull out this check to the caller

ok

you can check if the pv is assigned instead of introducing a new var

ok.
I add a .IsZero() method instead.