multiple criteria for calculating stock balance and profit

It took me quite a long time and still couldn't figure it out how to get the formula done.

What I want to do is to calculate the stock balance after selling. I want it to show on the same row of buying so that the market value can be calculated. Also, I need to calculate the profit of selling on the same row. Hope you understand what I'm talking about.

Please see the detail from the attached excel file.

Any help would be very appreciate.