Is it permissible to purchase baked goods in advance from a bakery at a low price, without specifying their type, with the intention of obtaining whatever remains at the end of the day?

Here there is ignorance regarding the object of sale, especially with the variation in the value of its types. What appears is that the sale is not valid in this manner due to the ignorance of the object of sale. And a sale conducted in this way is among the gharar (uncertainty) sales, which is a corrupt sale forbidden in Islam.