Coffee machine code kata

Code a bean-to-cup coffee machine. You can decide how much capacity the watertank has and how much half a cup / a cup is. (Aside: Why? Because I've always wanted to do it.)

Lights 

• brewing
• heating up
• clean waste container
• refill water
• no beans

Featues (grinding + brewing = duration until cup is finished)

• grinding (how much coffee)
• strong: 7 seconds
• normal: 5 seconds
• mild: 3 seconds
• brew half a cup, 15 seconds
• brew a cup, 30 seconds
• hot steam to preheat cups (blocks brewing and visa versa)

Buttons

• on / off (starts heating, heating always takes 20 seconds)
• half a cup / cup (default: half a cup)
• grinding
• pressed once: thin
• pressed twice: normal (default)
• pressed thrice: strong
• steam
• start

So if you turn it on and the heating light shows that it's heated up and you press the start button it would brew half a cup normal coffee. It would take: 20 seconds (heatup) + 5 seconds (grinding) + 15 seconds (brewing) = 40 seconds.

Imagine it as something like the thing shown below:

If you like to improve this kata, fork it on github and make a pullrequest.