agora/src/Agora/Utils.hs
2022-02-24 00:20:57 +01:00

283 lines
9.6 KiB
Haskell

-- | Plutarch utility functions that should be upstreamed or don't belong anywhere else
module Agora.Utils (
-- * Validator-level utility functions
passert,
pfind',
pfindDatum,
pfindDatum',
pvalueSpent,
ptxSignedBy,
paddValue,
plookup,
pfromMaybe,
psymbolValueOf,
passetClassValueOf,
passetClassValueOf',
pfindTxInByTxOutRef,
pfindMap,
-- * Functions which should (probably) not be upstreamed
anyOutput,
anyInput,
) where
--------------------------------------------------------------------------------
import Plutus.V1.Ledger.Value (AssetClass (..))
--------------------------------------------------------------------------------
import Plutarch.Api.V1 (
PAddress,
PCurrencySymbol,
PDatum,
PDatumHash,
PMap (PMap),
PMaybeData (PDJust),
PPubKeyHash,
PTokenName,
PTuple,
PTxInInfo (PTxInInfo),
PTxInfo (PTxInfo),
PTxOut (PTxOut),
PTxOutRef,
PValue (PValue),
)
import Plutarch.Builtin (ppairDataBuiltin)
import Plutarch.Internal (punsafeCoerce)
import Plutarch.Monadic qualified as P
--------------------------------------------------------------------------------
-- Validator-level utility functions
-- | Assert a particular bool, trace on falsehood. Use in monadic context
passert :: Term s PString -> Term s PBool -> Term s k -> Term s k
passert errorMessage check k = pif check k (ptraceError errorMessage)
-- | Find a datum with the given hash.
pfindDatum :: Term s (PDatumHash :--> PTxInfo :--> PMaybe PDatum)
pfindDatum = phoistAcyclic $
plam $ \datumHash txInfo'' -> P.do
PTxInfo txInfo' <- pmatch txInfo''
plookupTuple # datumHash #$ pfield @"data" # txInfo'
-- | Find a datum with the given hash. NOTE: this is unsafe in the sense that, if the data layout is wrong, this is UB.
pfindDatum' :: PIsData a => Term s (PDatumHash :--> PTxInfo :--> PMaybe (PAsData a))
pfindDatum' = phoistAcyclic $ plam $ \dh x -> punsafeCoerce $ pfindDatum # dh # x
-- | Check if a PubKeyHash signs this transaction
ptxSignedBy :: Term s (PTxInfo :--> PAsData PPubKeyHash :--> PBool)
ptxSignedBy = phoistAcyclic $
plam $ \txInfo' pkh -> P.do
txInfo <- pletFields @'["signatories"] txInfo'
pelem @PBuiltinList # pkh # txInfo.signatories
-- | Get the first element that matches a predicate or return Nothing
pfind' ::
PIsListLike list a =>
(Term s a -> Term s PBool) ->
Term s (list a :--> PMaybe a)
pfind' p =
precList
(\self x xs -> pif (p x) (pcon (PJust x)) (self # xs))
(const $ pcon PNothing)
-- | Get the first element that maps to a PJust in a list
pfindMap ::
PIsListLike list a =>
Term s ((a :--> PMaybe b) :--> list a :--> PMaybe b)
pfindMap =
phoistAcyclic $
plam $ \p ->
precList
( \self x xs ->
-- In the future, this should use `pmatchSum`, I believe?
pmatch (p # x) $ \case
PNothing -> self # xs
PJust v -> pcon (PJust v)
)
(const $ pcon PNothing)
-- | Find the value for a given key in an assoclist
plookup ::
(PEq a, PIsListLike list (PBuiltinPair a b)) =>
Term s (a :--> list (PBuiltinPair a b) :--> PMaybe b)
plookup =
phoistAcyclic $
plam $ \k xs ->
pmatch (pfind' (\p -> pfstBuiltin # p #== k) # xs) $ \case
PNothing -> pcon PNothing
PJust p -> pcon (PJust (psndBuiltin # p))
-- | Find the value for a given key in an assoclist which uses 'PTuple's
plookupTuple ::
(PEq a, PIsListLike list (PAsData (PTuple a b)), PIsData a, PIsData b) =>
Term s (a :--> list (PAsData (PTuple a b)) :--> PMaybe b)
plookupTuple =
phoistAcyclic $
plam $ \k xs ->
pmatch (pfind' (\p -> (pfield @"_0" # pfromData p) #== k) # xs) $ \case
PNothing -> pcon PNothing
PJust p -> pcon (PJust (pfield @"_1" # pfromData p))
-- | Extract a Maybe by providing a default value in case of Just
pfromMaybe :: forall a s. Term s (a :--> PMaybe a :--> a)
pfromMaybe = phoistAcyclic $
plam $ \e a ->
pmatch a $ \case
PJust a' -> a'
PNothing -> e
-- | Escape with a particular value on expecting 'Just'. For use in monadic context
pexpectJust :: forall r a s. Term s r -> Term s (PMaybe a) -> (Term s a -> Term s r) -> Term s r
pexpectJust escape ma f =
pmatch ma $ \case
PJust v -> f v
PNothing -> escape
-- | Get the sum of all values belonging to a particular CurrencySymbol
psymbolValueOf :: Term s (PCurrencySymbol :--> PValue :--> PInteger)
psymbolValueOf =
phoistAcyclic $
plam $ \sym value'' -> P.do
PValue value' <- pmatch value''
PMap value <- pmatch value'
m' <- pexpectJust 0 (plookup # pdata sym # value)
PMap m <- pmatch (pfromData m')
pfoldr # (plam $ \x v -> (pfromData $ psndBuiltin # x) + v) # 0 # m
-- | Extract amount from PValue belonging to a Plutarch-level asset class
passetClassValueOf ::
Term s (PCurrencySymbol :--> PTokenName :--> PValue :--> PInteger)
passetClassValueOf =
phoistAcyclic $
plam $ \sym token value'' -> P.do
PValue value' <- pmatch value''
PMap value <- pmatch value'
m' <- pexpectJust 0 (plookup # pdata sym # value)
PMap m <- pmatch (pfromData m')
v <- pexpectJust 0 (plookup # pdata token # m)
pfromData v
-- | Extract amount from PValue belonging to a Haskell-level AssetClass
passetClassValueOf' :: AssetClass -> Term s (PValue :--> PInteger)
passetClassValueOf' (AssetClass (sym, token)) =
passetClassValueOf # pconstant sym # pconstant token
-- | Union two maps using a merge function on collisions
pmapUnionWith :: forall k v s. PIsData v => Term s ((v :--> v :--> v) :--> PMap k v :--> PMap k v :--> PMap k v)
pmapUnionWith = phoistAcyclic $
-- TODO: this function is kinda suspect. I feel like a lot of optimizations could be done here
plam $ \f xs' ys' -> P.do
PMap xs <- pmatch xs'
PMap ys <- pmatch ys'
let ls =
pmap
# ( plam $ \p -> P.do
pf <- plet $ pfstBuiltin # p
ps <- plet $ psndBuiltin # p
pmatch (plookup # pf # ys) $ \case
PJust v ->
-- Data conversions here are silly, aren't they?
ppairDataBuiltin # pf # (pdata (f # pfromData ps # pfromData v))
PNothing -> p
)
# xs
rs =
pfilter
# ( plam $ \p ->
pnot # (pany # (plam $ \p' -> pfstBuiltin # p' #== pfstBuiltin # p) # xs)
)
# ys
pcon (PMap $ pconcat # ls # rs)
-- | Add two 'PValue's together
paddValue :: forall s. Term s (PValue :--> PValue :--> PValue)
paddValue = phoistAcyclic $
plam $ \a' b' -> P.do
PValue a <- pmatch a'
PValue b <- pmatch b'
pcon
( PValue $
pmapUnionWith # (plam $ \a' b' -> pmapUnionWith # (plam (+)) # a' # b') # a # b
)
-- | Sum of all value at input
pvalueSpent :: Term s (PTxInfo :--> PValue)
pvalueSpent = phoistAcyclic $
plam $ \txInfo' ->
pmatch txInfo' $ \(PTxInfo txInfo) ->
pfoldr
# ( plam $ \txInInfo' v ->
pmatch
(pfromData txInInfo')
$ \(PTxInInfo txInInfo) ->
paddValue
# (pmatch (pfield @"resolved" # txInInfo) $ \(PTxOut o) -> pfromData $ pfield @"value" # o)
# v
)
# pconstant mempty
# (pfield @"inputs" # txInfo)
-- | Find the TxInInfo by a TxOutRef
pfindTxInByTxOutRef :: Term s (PTxOutRef :--> PTxInfo :--> PMaybe PTxInInfo)
pfindTxInByTxOutRef = phoistAcyclic $
plam $ \txOutRef txInfo' ->
pmatch txInfo' $ \(PTxInfo txInfo) ->
pfindMap
# ( plam $ \txInInfo' ->
plet (pfromData txInInfo') $ \r ->
pmatch r $ \(PTxInInfo txInInfo) ->
pif
(pdata txOutRef #== pfield @"outRef" # txInInfo)
(pcon (PJust r))
(pcon PNothing)
)
#$ (pfield @"inputs" # txInfo)
--------------------------------------------------------------------------------
-- Functions which should (probably) not be upstreamed
-- | 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