agora/agora/Agora/Governor.hs
2022-05-10 19:55:41 +08:00

187 lines
6 KiB
Haskell

{-# LANGUAGE TemplateHaskell #-}
{- |
Module : Agora.Governor
Maintainer : connor@mlabs.city
Description: Governor entity scripts acting as authority of entire system.
Governor entity scripts acting as authority of entire system.
-}
module Agora.Governor (
-- * Haskell-land
GovernorDatum (..),
GovernorRedeemer (..),
Governor (..),
-- * Plutarch-land
PGovernorDatum (..),
PGovernorRedeemer (..),
-- * Utilities
pgetNextProposalId,
getNextProposalId,
governorDatumValid,
) where
--------------------------------------------------------------------------------
import Control.Applicative (Const)
import GHC.Generics qualified as GHC
import Generics.SOP (Generic, I (I))
--------------------------------------------------------------------------------
import Agora.Proposal (
PProposalId (..),
PProposalThresholds (..),
ProposalId (ProposalId),
ProposalThresholds,
)
import Agora.SafeMoney (GTTag)
--------------------------------------------------------------------------------
import Plutarch.DataRepr (
DerivePConstantViaData (..),
PDataFields,
PIsDataReprInstances (PIsDataReprInstances),
)
import Plutarch.Lift (PConstantDecl, PUnsafeLiftDecl (..))
import Plutarch.Monadic qualified as P
import Plutarch.SafeMoney (Tagged (..), puntag)
import Plutarch.TryFrom (PTryFrom (..))
import Plutarch.Unsafe (punsafeCoerce)
--------------------------------------------------------------------------------
import Plutus.V1.Ledger.Api (TxOutRef)
import Plutus.V1.Ledger.Value (AssetClass (..))
import PlutusTx qualified
--------------------------------------------------------------------------------
-- | Datum for the Governor script.
data GovernorDatum = GovernorDatum
{ proposalThresholds :: ProposalThresholds
-- ^ Gets copied over upon creation of a 'Agora.Proposal.ProposalDatum'.
, nextProposalId :: ProposalId
-- ^ What tag the next proposal will get upon creating.
}
deriving stock (Show, GHC.Generic)
PlutusTx.makeIsDataIndexed ''GovernorDatum [('GovernorDatum, 0)]
{- | Redeemer for Governor script. The governor has two primary
responsibilities:
1. The gating of Proposal creation.
2. The gating of minting authority tokens.
Parameters of the governor can also be mutated by an effect.
-}
data GovernorRedeemer
= -- | Checks that a proposal was created lawfully, and allows it.
CreateProposal
| -- | Checks that a SINGLE proposal finished correctly,
-- and allows minting GATs for each effect script.
MintGATs
| -- | Allows effects to mutate the parameters.
MutateGovernor
deriving stock (Show, GHC.Generic)
PlutusTx.makeIsDataIndexed
''GovernorRedeemer
[ ('CreateProposal, 0)
, ('MintGATs, 1)
, ('MutateGovernor, 2)
]
-- | Parameters for creating Governor scripts.
data Governor = Governor
{ gstOutRef :: TxOutRef
-- ^ Referenced utxo will be spent to mint the GST.
, gtClassRef :: Tagged GTTag AssetClass
-- ^ Governance token of the system.
, maximumCosigners :: Integer
-- ^ Arbitrary limit for maximum amount of cosigners on a proposal.
-- See `Agora.Proposal.proposalDatumValid`.
}
--------------------------------------------------------------------------------
-- | Plutarch-level datum for the Governor script.
newtype PGovernorDatum (s :: S) = PGovernorDatum
{ getGovernorDatum ::
Term
s
( PDataRecord
'[ "proposalThresholds" ':= PProposalThresholds
, "nextProposalId" ':= PProposalId
]
)
}
deriving stock (GHC.Generic)
deriving anyclass (Generic)
deriving anyclass (PIsDataRepr)
deriving
(PlutusType, PIsData, PDataFields, PEq)
via PIsDataReprInstances PGovernorDatum
instance PUnsafeLiftDecl PGovernorDatum where type PLifted PGovernorDatum = GovernorDatum
deriving via (DerivePConstantViaData GovernorDatum PGovernorDatum) instance (PConstantDecl GovernorDatum)
-- FIXME: derive this via 'PIsDataReprInstances'
-- Blocked by: PProposalThresholds
instance PTryFrom PData (PAsData PGovernorDatum) where
type PTryFromExcess PData (PAsData PGovernorDatum) = Const ()
ptryFrom' d k = k (punsafeCoerce d, ())
-- | Plutarch-level version of 'GovernorRedeemer'.
data PGovernorRedeemer (s :: S)
= PCreateProposal (Term s (PDataRecord '[]))
| PMintGATs (Term s (PDataRecord '[]))
| PMutateGovernor (Term s (PDataRecord '[]))
deriving stock (GHC.Generic)
deriving anyclass (Generic)
deriving anyclass (PIsDataRepr)
deriving
(PlutusType, PIsData)
via PIsDataReprInstances PGovernorRedeemer
instance PUnsafeLiftDecl PGovernorRedeemer where type PLifted PGovernorRedeemer = GovernorRedeemer
deriving via (DerivePConstantViaData GovernorRedeemer PGovernorRedeemer) instance (PConstantDecl GovernorRedeemer)
deriving via PAsData (PIsDataReprInstances PGovernorRedeemer) instance PTryFrom PData (PAsData PGovernorRedeemer)
--------------------------------------------------------------------------------
-- | Plutrach version of 'getNextProposalId'.
pgetNextProposalId :: Term s (PProposalId :--> PProposalId)
pgetNextProposalId = phoistAcyclic $ plam $ \(pto -> pid) -> pcon $ PProposalId $ pid + 1
-- | Get next proposal id.
getNextProposalId :: ProposalId -> ProposalId
getNextProposalId (ProposalId pid) = ProposalId $ pid + 1
--------------------------------------------------------------------------------
governorDatumValid :: Term s (PGovernorDatum :--> PBool)
governorDatumValid = phoistAcyclic $
plam $ \datum -> P.do
thresholds <-
pletFields @'["execute", "draft", "vote"] $
pfield @"proposalThresholds" # datum
execute <- plet $ puntag thresholds.execute
draft <- plet $ puntag thresholds.draft
vote <- plet $ puntag thresholds.vote
foldr1
(#&&)
[ ptraceIfFalse "Execute threshold is less than or equal to" $ 0 #<= execute
, ptraceIfFalse "Draft threshold is less than or equal to " $ 0 #<= draft
, ptraceIfFalse "Vote threshold is less than or equal to " $ 0 #<= vote
, ptraceIfFalse "Draft threshold is less than vote threshold" $ draft #<= vote
, ptraceIfFalse "Execute threshold is less than vote threshold" $ vote #< execute
]