Now that I have "register pubkey" I started writing support for "register escrow agent", "create contract", "trade contract" and "settle contract" -- but found I have to rethink things again. For example, I had planned to have CLAMspeech declarations like:
register escrow agent 73 USD
in which the controller of the pubkey registered to 73 indicates his/her willingness to act as an escrow agent under the given terms until the timeout.
Obviously this tx should be signed by the corresponding private key. The easiest way to enforce this is to check that the first input to the tx with the CLAMspeech came from the corresponding address. In which case the pubkey is explicitly in the tx already, and so why did it need to be registered in advance?
Be careful. Just because one of my privkeys signed the first input to a transaction, it doesn't mean I agree with the content of the CLAMspeech. The transaction could be a withdrawal from Just-Dice. When withdrawing from Just-Dice you can specify any CLAMspeech you like. The transaction's inputs will be signed by private keys in the hot wallet, but the owner of those keys doesn't endorse the content of the CLAMspeech.
In other words, it's been one of those days of taking two steps back.
I worry that we're going to end up hard-coding many different similar-but-different features into the CLAM client, and wonder if there's some way we could generalize it so we don't have to edit C++ code for the next person to dream up a use for CLAMspeech.
(Cue sighs and groans from Creative and Kef...)