set up some init code for preBalanceTxM

src/PreBalanceTx.purs

@@ -1,11 +1,14 @@
 module PreBalanceTx
   ( preBalanceTx
+  , preBalanceTxM
   ) where
 
 import Prelude
+import Control.Monad.Reader.Trans (runReaderT)
+import Control.Monad.Trans.Class (lift)
 import Data.Array as Array
 import Data.BigInt (BigInt, fromInt)
-import Data.Either (Either(..), hush, note)
+import Data.Either (Either(..), fromRight, hush, isRight, note)
 import Data.Foldable as Foldable
 import Data.List ((:), List(..), partition)
 import Data.Map as Map
@@ -14,24 +17,57 @@ import Data.Newtype (over, unwrap, wrap)
 import Data.Set (Set)
 import Data.Set as Set
 import Data.Tuple.Nested ((/\), type (/\))
+import Effect.Aff (Aff)
+import Undefined (undefined)
 
+import Ogmios (QueryConfig, QueryM(..))
 import ProtocolParametersAlonzo (protocolParamUTxOCostPerWord)
 import Types.Ada (adaSymbol, fromValue, getLovelace, lovelaceValueOf)
-import Types.Transaction (Address, Credential(..), RequiredSigner, TransactionInput, TransactionOutput(..), TxBody(..), Utxo)
+import Types.Transaction (Address, Credential(..), RequiredSigner, Transaction(..), TransactionInput, TransactionOutput(..), TxBody(..), Utxo, UtxoM)
 import Types.Value (emptyValue, flattenValue, geq, getValue, isAdaOnly, isPos, isZero, minus, Value(..))
 
 -- This module replicates functionality from
 -- https://github.com/mlabs-haskell/mlabs-pab/blob/master/src/MLabsPAB/PreBalance.hs
 
-preBalanceTx ::
-  Array (TransactionOutput /\ BigInt) ->
-  BigInt ->
-  Utxo ->
-  Address ->
-  Map.Map Address RequiredSigner ->
-  Array Address ->
-  TxBody ->
-  Either String TxBody
+-- TO DO: convert utxosAt from Ogmios to Transaction space.
+utxosAt :: Address -> QueryM UtxoM
+utxosAt = undefined
+
+preBalanceTxM
+  :: QueryConfig
+  -> Address
+  -> Map.Map Address RequiredSigner -- FIX ME: take from unbalanced tx?
+  -> Array Address -- FIX ME: take from unbalanced tx?
+  -> Transaction -- unbalanced transaction, FIX ME: do we need a newtype wrapper?
+  -> Aff (Either String Transaction)
+preBalanceTxM qConfig ownAddr addReqSigners requiredAddrs unbalancedTx =
+  runReaderT
+    do
+      utxos <- unwrap <$> utxosAt ownAddr -- Do we want :: Either String UtxoM here?
+      let utxoIndex = utxos  -- FIX ME: include newtype wrapper? UNWRAP
+          unwrapUnbalancedTx = unwrap unbalancedTx
+
+      pure
+        $ (wrap <<< unwrapUnbalancedTx { body = _ })
+        <$> preBalanceTx
+              []
+              zero
+              utxoIndex
+              ownAddr
+              addReqSigners
+              requiredAddrs
+              unwrapUnbalancedTx.body
+  qConfig
+
+preBalanceTx
+  :: Array (TransactionOutput /\ BigInt)
+  -> BigInt
+  -> Utxo
+  -> Address
+  -> Map.Map Address RequiredSigner
+  -> Array Address
+  -> TxBody
+  -> Either String TxBody
 preBalanceTx minUtxos fees utxos ownAddr addReqSigners requiredAddrs tx =
   addTxCollaterals utxos tx -- Take a single Ada only utxo collateral
     >>= balanceTxIns utxos fees -- Add input fees for the Ada only collateral

src/Types/Transaction.purs

@@ -2,9 +2,11 @@ module Types.Transaction where
 
 import Prelude
 import Data.BigInt (BigInt)
+import Data.Generic.Rep (class Generic)
 import Data.Map (Map)
 import Data.Maybe (Maybe)
 import Data.Newtype (class Newtype)
+import Data.Show.Generic (genericShow)
 import Data.Tuple.Nested (type (/\))
 
 import Types.Value (Value)
@@ -15,6 +17,7 @@ newtype Transaction = Transaction {
   is_valid :: Boolean,
   auxiliary_data :: Maybe AuxiliaryData
 }
+derive instance newtypeTransaction :: Newtype Transaction _
 
 newtype TxBody = TxBody
   { inputs :: Array TransactionInput,
@@ -79,16 +82,28 @@ newtype TransactionInput = TransactionInput
     index :: BigInt -- u32 TransactionIndex
   }
 derive instance eqTransactionInput :: Eq TransactionInput
+derive instance genericTransactionInput :: Generic TransactionInput _
 derive instance ordTransactionInput :: Ord TransactionInput
 
+instance showTransactionInput :: Show TransactionInput where
+  show = genericShow
+
 newtype TransactionOutput = TransactionOutput
   { address :: Address,
     amount :: Value,
     data_hash :: Maybe String -- DataHash>,
   }
 derive instance eqTransactionOutput :: Eq TransactionOutput
+derive instance genericTransactionOutput :: Generic TransactionOutput _
 derive instance newtypeTransactionOutput :: Newtype TransactionOutput _
 
+instance showTransactionOutput :: Show TransactionOutput where
+  show = genericShow
+
+newtype UtxoM = UtxoM Utxo
+derive instance newtypeUtxoM :: Newtype UtxoM _
+derive newtype instance showUtxoM :: Show UtxoM
+
 type Utxo = Map TransactionInput TransactionOutput
 
 newtype Coin = Coin BigInt
@@ -99,21 +114,33 @@ newtype Address = Address
   { "AddrType" :: BaseAddress
   }
 derive instance eqAddress :: Eq Address
+derive instance genericAddress :: Generic Address _
 derive instance ordAddress :: Ord Address
 derive instance newtypeAddress :: Newtype Address _
 
+instance showAddress :: Show Address where
+  show = genericShow
+
 newtype BaseAddress = BaseAddress
   { network :: Int, -- u8,
     stake :: Credential,
     payment :: Credential
   }
 derive instance eqBaseAddress :: Eq BaseAddress
+derive instance genericBaseAddress :: Generic BaseAddress _
 derive instance ordBaseAddress :: Ord BaseAddress
 derive instance newtypeBaseAddress :: Newtype BaseAddress _
 
+instance showBaseAddress :: Show BaseAddress where
+  show = genericShow
+
 newtype Credential = Credential String
 derive instance eqCredential :: Eq Credential
+derive instance genericCredential :: Generic Credential _
 derive instance ordCredential :: Ord Credential
+
+instance showCredential :: Show Credential where
+  show = genericShow
 -- Below comes from Plutus API:
 -- data Credential = PubKeyCredential String | ScriptCredential String