Magento

hello,

I would like to make \"shop\" based on magento. It should looks like this example: cart is can (total weight 1kg). Shopper can buy balls (weight 50g), rubber (weight 20g), stickers (weight 80g). It should count weight in can automatically so when it reaches 1kg javascript should say \"your can is full, please add second can\” and user should be able to add and fill another can.
I would like to have cans with differnet capacities as well.

Any idea how to do this?

I believe you can accomplish this with the rules engine.