Smart_contract_example

{-# LANGUAGE NumericUnderscores #-}
{-# LANGUAGE OverloadedStrings  #-}

module DeliveryContractWithOracle where

import Language.Marlowe.Extended.V1

main :: IO ()
main = printJSON deliveryContract

-- Define the number of slots in two weeks as an Integer and convert to Timeout
slotsInTwoWeeks :: Timeout
slotsInTwoWeeks = let
    slots = (60 * 60 * 24 * 14) `div` 20 -- Calculate as Integer
    in fromInteger slots -- Convert to Timeout

-- Define parties involved in the contract
seller, buyer, oracle :: Party
seller = Role "Seller"
buyer = Role "Buyer"
oracle = Role "USPS_Oracle" 

-- Define deposits from each party
sellerDeposit, buyerDeposit :: Value
sellerDeposit = Constant 100_000_000 -- 100 ADA in Lovelaces
buyerDeposit = Constant 100_000_000 -- 100 ADA in Lovelaces

-- Define the choice for the oracle
deliveryConfirmation :: ChoiceId
deliveryConfirmation = ChoiceId "Package Delivered" oracle

-- Define the contract
deliveryContract :: Contract
deliveryContract =
    When [Case (Deposit seller seller ada sellerDeposit)
              (When [Case (Deposit buyer buyer ada buyerDeposit)
                        (When [Case (Choice deliveryConfirmation [Bound 1 1])
                                  (Pay seller (Party buyer) ada sellerDeposit
                                  $ Pay buyer (Party seller) ada buyerDeposit
                                  Close)]
                              (slotsInTwoWeeks) -- Waiting for oracle's confirmation
                              Close)] -- Buyer's deposit
                    (slotsInTwoWeeks) -- Waiting for seller's deposit
                    Close)]
         (slotsInTwoWeeks) -- Initial timeout
         Close -- Contract closure in case of timeout