stake validator basics

This commit is contained in:
Emily Martins 2022-02-24 00:20:57 +01:00
parent b48d797747
commit 3a1fba39b9
4 changed files with 192 additions and 102 deletions

View file

@ -1,10 +1,11 @@
{-# LANGUAGE DeriveGeneric #-}
{-# LANGUAGE PolyKinds #-}
{-# LANGUAGE UndecidableInstances #-}
-- | Vote-lockable stake UTXOs holding GT
module Agora.Stake (
StakeDatum (..),
StakeAction (..),
PStakeDatum (..),
PStakeAction (..),
Stake (..),
stakePolicy,
stakeValidator,
@ -22,6 +23,7 @@ import Prelude
--------------------------------------------------------------------------------
import Plutarch (popaque)
import Plutarch.Api.V1
import Plutarch.DataRepr (
PDataFields,
@ -39,19 +41,19 @@ import Agora.Utils
data Stake (gt :: MoneyClass) = Stake
data StakeAction (gt :: MoneyClass) (s :: S)
data PStakeAction (gt :: MoneyClass) (s :: S)
= -- | Deposit or withdraw a discrete amount of the staked governance token
DepositWithdraw (Term s (PDataRecord '["delta" ':= Discrete gt]))
PDepositWithdraw (Term s (PDataRecord '["delta" ':= Discrete gt]))
| -- | Destroy a stake, retrieving its LQ, the minimum ADA and any other assets
Destroy (Term s (PDataRecord '[]))
PDestroy (Term s (PDataRecord '[]))
deriving stock (GHC.Generic)
deriving anyclass (Generic)
deriving anyclass (PIsDataRepr)
deriving
(PlutusType, PIsData)
via PIsDataReprInstances (StakeAction gt)
via PIsDataReprInstances (PStakeAction gt)
newtype StakeDatum (gt :: MoneyClass) (s :: S) = StakeDatum
newtype PStakeDatum (gt :: MoneyClass) (s :: S) = PStakeDatum
{ getStakeDatum ::
( Term
s
@ -67,51 +69,7 @@ newtype StakeDatum (gt :: MoneyClass) (s :: S) = StakeDatum
deriving anyclass (PIsDataRepr)
deriving
(PlutusType, PIsData, PDataFields)
via (PIsDataReprInstances (StakeDatum gt))
-- | Check if any output matches the predicate
anyOutput ::
forall (datum :: PType) s.
( PIsData datum
) =>
Term s (PTxInfo :--> (PValue :--> PAddress :--> datum :--> PBool) :--> PBool)
anyOutput = phoistAcyclic $
plam $ \txInfo' predicate -> P.do
txInfo <- pletFields @'["outputs"] txInfo'
pany
# ( plam $ \txOut'' -> P.do
PTxOut txOut' <- pmatch (pfromData txOut'')
txOut <- pletFields @'["value", "datumHash", "address"] txOut'
PDJust dh <- pmatch txOut.datumHash
pmatch (pfindDatum' @datum # (pfield @"_0" # dh) # txInfo') $ \case
PJust datum -> P.do
predicate # txOut.value # txOut.address # pfromData datum
PNothing -> pcon PFalse
)
# pfromData txInfo.outputs
-- | Check if any (resolved) input matches the predicate
anyInput ::
forall (datum :: PType) s.
( PIsData datum
) =>
Term s (PTxInfo :--> (PValue :--> PAddress :--> datum :--> PBool) :--> PBool)
anyInput = phoistAcyclic $
plam $ \txInfo' predicate -> P.do
txInfo <- pletFields @'["inputs"] txInfo'
pany
# ( plam $ \txInInfo'' -> P.do
PTxInInfo txInInfo' <- pmatch (pfromData txInInfo'')
let txOut'' = pfield @"resolved" # txInInfo'
PTxOut txOut' <- pmatch (pfromData txOut'')
txOut <- pletFields @'["value", "datumHash", "address"] txOut'
PDJust dh <- pmatch txOut.datumHash
pmatch (pfindDatum' @datum # (pfield @"_0" # dh) # txInfo') $ \case
PJust datum -> P.do
predicate # txOut.value # txOut.address # pfromData datum
PNothing -> pcon PFalse
)
# pfromData txInfo.inputs
via (PIsDataReprInstances (PStakeDatum gt))
--------------------------------------------------------------------------------
--
@ -135,7 +93,7 @@ stakePolicy ::
, gt ~ '(ac, n, scale)
) =>
Stake gt ->
Term s (PData :--> PAsData PScriptContext :--> PUnit)
Term s PMintingPolicy
stakePolicy _stake =
plam $ \_redeemer ctx' -> P.do
ctx <- pletFields @'["txInfo", "purpose"] ctx'
@ -144,36 +102,35 @@ stakePolicy _stake =
PMinting ownSymbol' <- pmatch $ pfromData ctx.purpose
ownSymbol <- plet $ pfield @"_0" # ownSymbol'
valueSpent <- plet $ pvalueSpent # pfromData txInfo'
spentST <- plet $ psymbolValueOf # ownSymbol #$ pvalueSpent # pfromData txInfo'
mintedST <- plet $ psymbolValueOf # ownSymbol # txInfo.mint
-- inputST <- plet $ stOf # (pvalueSpent # pfromData txInfo')
let burning = P.do
passert "ST at inputs must be 1" $
psymbolValueOf # ownSymbol # valueSpent #== 1
spentST #== 1
passert "ST burned" $
mintedST #== -1
passert "An unlocked input existed containing an ST" $
anyInput @(StakeDatum gt) # pfromData txInfo'
anyInput @(PStakeDatum gt) # pfromData txInfo'
#$ plam
$ \value _ stakeDatum' -> P.do
let hasST = psymbolValueOf # ownSymbol # value #== 1
let unlocked = pnot # (stakeLocked # stakeDatum')
hasST #&& unlocked
pconstant ()
popaque (pconstant ())
let minting = P.do
passert "ST at inputs must be 0" $
psymbolValueOf # ownSymbol # valueSpent #== 0
spentST #== 0
passert "Minted ST must be exactly 1" $
mintedST #== 1
passert "A UTXO must exist with the correct output" $
anyOutput @(StakeDatum gt) # pfromData txInfo'
anyOutput @(PStakeDatum gt) # pfromData txInfo'
#$ plam
$ \value address stakeDatum' -> P.do
let cred = pfield @"credential" # address
@ -200,17 +157,10 @@ stakePolicy _stake =
let valueCorrect = pdata value #== pdata expectedValue
ownerSignsTransaction #&& valueCorrect
pconstant ()
popaque (pconstant ())
pif (0 #< mintedST) minting burning
-- | Check whether a Stake is locked. If it is locked, various actions are unavailable.
stakeLocked :: forall (gt :: MoneyClass) s. Term s (StakeDatum gt :--> PBool)
stakeLocked = phoistAcyclic $
plam $ \_stakeDatum ->
-- TODO: when we extend this to support proposals, this will need to do something
pcon PFalse
--------------------------------------------------------------------------------
stakeValidator ::
forall (gt :: MoneyClass) ac n scale s.
@ -219,11 +169,62 @@ stakeValidator ::
, gt ~ '(ac, n, scale)
) =>
Stake gt ->
Term s (PData :--> PData :--> PAsData PScriptContext :--> PUnit)
stakeValidator _stake =
Term s PValidator
stakeValidator stake =
plam $ \datum redeemer ctx' -> P.do
_ctx <- pletFields @'["txInfo", "purpose"] ctx'
let _stakeAction = punsafeCoerce redeemer :: Term s (StakeAction gt)
_stakeDatum <- pletFields @'["owner"] (punsafeCoerce datum :: Term s (StakeDatum gt))
ctx <- pletFields @'["txInfo", "purpose"] ctx'
txInfo' <- plet ctx.txInfo
txInfo <- pletFields @'["mint", "inputs", "outputs"] txInfo'
let stakeAction = punsafeCoerce redeemer :: Term s (PStakeAction gt)
let stakeDatum' = punsafeCoerce datum :: Term s (PStakeDatum gt)
stakeDatum <- pletFields @'["owner", "stakedAmount"] stakeDatum'
pconstant ()
PSpending txOutRef <- pmatch $ pfromData ctx.purpose
PJust txInInfo <- pmatch $ pfindTxInByTxOutRef # (pfield @"_0" # txOutRef) # txInfo'
ownAddress <- plet $ pfield @"address" #$ pfield @"resolved" # txInInfo
let continuingValue = pfield @"value" #$ pfield @"resolved" # txInInfo
stCurrencySymbol <- plet $ pconstant $ mintingPolicySymbol $ mkMintingPolicy (stakePolicy stake)
mintedST <- plet $ psymbolValueOf # stCurrencySymbol # txInfo.mint
spentST <- plet $ psymbolValueOf # stCurrencySymbol #$ pvalueSpent # txInfo'
pmatch stakeAction $ \case
PDestroy _ -> P.do
passert "ST at inputs must be 1" $
spentST #== 1
passert "Should burn ST" $
mintedST #== -1
passert "Stake unlocked" $
pnot #$ stakeLocked # stakeDatum'
popaque (pconstant ())
PDepositWithdraw r -> P.do
passert "ST at inputs must be 1" $
spentST #== 1
passert "Stake unlocked" $
pnot #$ stakeLocked # stakeDatum'
passert "A UTXO must exist with the correct output" $
anyOutput @(PStakeDatum gt) # txInfo'
#$ plam
$ \value address newStakeDatum' -> P.do
newStakeDatum <- pletFields @'["owner", "stakedAmount"] newStakeDatum'
delta <- plet $ pfield @"delta" # r
let isScriptAddress = pdata address #== ownAddress
let correctOutputDatum =
stakeDatum.owner #== newStakeDatum.owner
#&& (paddDiscrete # stakeDatum.stakedAmount # delta) #== newStakeDatum.stakedAmount
let expectedValue = paddValue # continuingValue # (discreteValue # delta)
-- TODO: As above, needs to be >=, rather than ==
let correctValue = pdata value #== pdata expectedValue
isScriptAddress #&& correctOutputDatum #&& correctValue
popaque (pconstant ())
--------------------------------------------------------------------------------
-- | Check whether a Stake is locked. If it is locked, various actions are unavailable.
stakeLocked :: forall (gt :: MoneyClass) s. Term s (PStakeDatum gt :--> PBool)
stakeLocked = phoistAcyclic $
plam $ \_stakeDatum ->
-- TODO: when we extend this to support proposals, this will need to do something
pcon PFalse