I'm trying to squash the availability view of n-items into a single day column in an availability calendar. The use case is for reserving products. We can have n-pieces of any particular product, say bicycles, kayaks, etc. We may have two pieces of a product or three hundred pieces of it.
Because of the possibility of large amounts of reservable items of the same type, we can't use the normal 2D resource calendar (where one axis specifies the specific resource to be reserved, and the other axis specifies time). If there are 100 rows of items, it quickly becomes a chore to find a timeframe where 20 pieces of them would be available at the same time.
Before entering our reservation view, users pick how many pieces of the specific product they want. Users can reserve 0-N pieces, where N is the total amount of items we have of a specific product. After that, they're presented with a time/calendar view that has open slots for times when there is sufficient equipment available. If there is sufficient equipment available, users can reserve the items for one to eight hours.
My problem is that I don't know how I could visualize the following or similar cases:
Say we have a product. We have two pieces of this product, labeled item A and item B. Item A is reserved from 12:00 to 13.59, and item B is reserved from 14.00 to 15:59. A user wants to reserve 1 piece of item, from 12:00 to 15:59 (but we don't know this). There is technically one item free for the whole desired duration, but it's not the same item for the entire duration.
Can I somehow convey to users that it's possible to rent from 12:00 to 15:59, but he/she has to switch the item midway? Can I somehow show that if the reservations begins before 14.00, you can only reserve it to 14:00? Is there a better way of visualizing squashed availability of n-items? Should I even try to visualize it?
I could simply force all reservations to prefer item A, leaving item B free for reservation. But this would cause uneven wear in the items in the long run.