Plutus Pioneers Week03 Homework

validator.hs

{-# INLINABLE mkValidator #-}
-- This should validate if either beneficiary1 has signed the transaction and the current slot is before or at the deadline
-- or if beneficiary2 has signed the transaction and the deadline has passed.
mkValidator :: VestingDatum -> () -> ScriptContext -> Bool
mkValidator datum _ sc = traceIfFalse "cannot grab" (beneficiary1Grab || beneficiary2Grab)
    where
        info :: TxInfo
        info = scriptContextTxInfo sc

        beneficiary1Grab :: Bool
        beneficiary1Grab = currentSlotBeforeOrAtDeadline && signedByBeneficiary1

        currentSlotBeforeOrAtDeadline :: Bool
        -- the current slot is before or at the deadline
        currentSlotBeforeOrAtDeadline = contains (to $ deadline datum) $ txInfoValidRange info
        
        signedByBeneficiary1 :: Bool
        signedByBeneficiary1 = txSignedBy info $ unPaymentPubKeyHash $ beneficiary1 datum

        beneficiary2Grab :: Bool
        beneficiary2Grab = currentSlotAfterDeadline && signedByBeneficiary2

        currentSlotAfterDeadline :: Bool
        -- the current slot is AFTER the deadline
        currentSlotAfterDeadline = not $ overlaps (to $ deadline datum) $ txInfoValidRange info
        
        signedByBeneficiary2 :: Bool
        signedByBeneficiary2 = txSignedBy info $ unPaymentPubKeyHash $ beneficiary2 datum