Plutus Serialization and contract tests (#60)

* adaToLovelace helper method added

* Fix policyId generation for Plutus script and serialization issues

* More address tests

* Contract transaction tests

* ScriptUtxoSelection interface and default impl

* Fixed script data hash generation. PlutusObjectConverter interface

* New test added for multi token transfer in one transaction

src/integration-test/java/com/bloxbean/cardano/client/backend/api/helper/TransactionHelperServiceIT.java

@@ -319,6 +319,71 @@ void transferMultiAssetMultiPayments_whenSingleSender() throws CborSerialization
         assertThat(result.isSuccessful(), is(true));
     }
 
+    @Test
+    void transferMultiAssetMultiPayments_whenSingleSender_multipleToken() throws CborSerializationException, AddressExcepion, ApiException {
+        //Sender address : addr_test1qzx9hu8j4ah3auytk0mwcupd69hpc52t0cw39a65ndrah86djs784u92a3m5w475w3w35tyd6v3qumkze80j8a6h5tuqq5xe8y
+        String senderMnemonic = "damp wish scrub sentence vibrant gauge tumble raven game extend winner acid side amused vote edge affair buzz hospital slogan patient drum day vital";
+        Account sender = new Account(Networks.testnet(), senderMnemonic);
+
+        String receiver1 = "addr_test1qqwpl7h3g84mhr36wpetk904p7fchx2vst0z696lxk8ujsjyruqwmlsm344gfux3nsj6njyzj3ppvrqtt36cp9xyydzqzumz82";
+        String receiver2 = "addr_test1qz7r5eu2jg0hx470mmf79vpgueaggh22pmayry8xrre5grtpyy9s8u2heru58a4r68wysmdw9v40zznttmwrg0a6v9tq36pjak";
+        String receiver3 = "addr_test1qrp6x6aq2m28xhvxhqzufl0ff7x8gmzjejssrk29mx0q829dsty3hzmrl2k8jhwzghgxuzfjatgxlhg9wtl6ecv0v3cqf92rnh";
+        String receiver4 = "addr_test1qzj02w9f2lv3ayekxwr3hdxvn2umf3hyw6azze4rtczxzuwljt3yugepv88k3htyr60llrcj4a52hlytaka7jj3kf85szkyp6l";
+
+        PaymentTransaction paymentTransaction1 =
+                PaymentTransaction.builder()
+                        .sender(sender)
+                        .receiver(receiver1)
+                        .unit(LOVELACE)
+                        .amount(BigInteger.valueOf(1000000))
+                        .fee(BigInteger.valueOf(4000)) //some low fee (invalid). Just for testing
+                        .build();
+
+        PaymentTransaction paymentTransaction2 =
+                PaymentTransaction.builder()
+                        .sender(sender)
+                        .receiver(receiver2)
+                        .unit("6b248bf1bbfac692610ca7e9873f988dc5e358b9229be8d6363aedd34d59546f6b656e")
+                        .amount(BigInteger.valueOf(15))
+                        .build();
+
+        PaymentTransaction paymentTransaction3 =
+                PaymentTransaction.builder()
+                        .sender(sender)
+                        .receiver(receiver3)
+                        .amount(BigInteger.valueOf(4))
+                        .unit("329728f73683fe04364631c27a7912538c116d802416ca1eaf2d7a96736174636f696e")
+                        .build();
+
+        PaymentTransaction paymentTransaction4 =
+                PaymentTransaction.builder()
+                        .sender(sender)
+                        .receiver(receiver4)
+                        .amount(BigInteger.valueOf(2))
+                        .unit("b9bd3fb4511908402fbef848eece773bb44c867c25ac8c08d9ec3313696e746a")
+                        .build();
+
+        //Calculate total fee for all 4 payment transactions and set in one of the payment transaction
+        BigInteger fee = feeCalculationService.calculateFee(Arrays.asList(paymentTransaction1, paymentTransaction2, paymentTransaction3, paymentTransaction4),
+                TransactionDetailsParams
+                        .builder()
+                        .ttl(getTtl())
+                        .build(), null);
+        paymentTransaction1.setFee(fee);
+
+        Result<TransactionResult> result = transactionHelperService.transfer(Arrays.asList(paymentTransaction1, paymentTransaction2, paymentTransaction3, paymentTransaction4),
+                TransactionDetailsParams.builder().ttl(getTtl()).build());
+
+        if(result.isSuccessful())
+            System.out.println("Transaction Id: " + result.getValue());
+        else
+            System.out.println("Transaction failed: " + result);
+
+        System.out.println(result);
+        waitForTransaction(result);
+        assertThat(result.isSuccessful(), is(true));
+    }
+
     @Test
     void mintToken() throws CborSerializationException, AddressExcepion, ApiException {
 

src/main/java/com/bloxbean/cardano/client/common/ADAConversionUtil.java

@@ -36,4 +36,8 @@ public static BigInteger assetFromDecimal(BigDecimal doubleAmout, long decimals)
 
         return amount.toBigInteger();
     }
+
+    public static BigInteger adaToLovelace(double amount) {
+        return adaToLovelace(BigDecimal.valueOf(amount));
+    }
 }

src/main/java/com/bloxbean/cardano/client/plutus/api/PlutusObjectConverter.java

@@ -0,0 +1,11 @@
+package com.bloxbean.cardano.client.plutus.api;
+
+import com.bloxbean.cardano.client.transaction.spec.ConstrPlutusData;
+import com.bloxbean.cardano.client.transaction.spec.PlutusData;
+
+public interface PlutusObjectConverter {
+
+    public ConstrPlutusData convertToPlutusData(Object o);
+
+    public <T> T convertToObject(PlutusData plutusData, Class<T> tClass);
+}

src/main/java/com/bloxbean/cardano/client/plutus/api/ScriptUtxoSelection.java

@@ -0,0 +1,48 @@
+package com.bloxbean.cardano.client.plutus.api;
+
+import com.bloxbean.cardano.client.backend.exception.ApiException;
+import com.bloxbean.cardano.client.backend.model.Utxo;
+
+import java.util.List;
+import java.util.Set;
+import java.util.function.Predicate;
+
+public interface ScriptUtxoSelection {
+    /**
+     * Find the first utxo matching the predicate
+     * @param scriptAddress Script address
+     * @param predicate Predicate to filter utxos
+     * @return Utxo
+     * @throws ApiException
+     */
+    Utxo findFirst(String scriptAddress, Predicate<Utxo> predicate) throws ApiException;
+
+    /**
+     * Find the first utxo matching the predicate
+     * @param scriptAddress Script address
+     * @param predicate Predicate to filter utxos
+     * @param excludeUtxos Utxos to exclude
+     * @return Utxo
+     * @throws ApiException
+     */
+    Utxo findFirst(String scriptAddress, Predicate<Utxo> predicate, Set<Utxo> excludeUtxos) throws ApiException;
+
+    /**
+     * Find all utxos matching the predicate
+     * @param scriptAddress Script address
+     * @param predicate Predicate to filter utxos
+     * @return List of Utxos
+     * @throws ApiException
+     */
+    List<Utxo> findAll(String scriptAddress, Predicate<Utxo> predicate) throws ApiException;
+
+    /**
+     * Find all utxos matching the predicate
+     * @param scriptAddress ScriptAddress Script address
+     * @param predicate Predicate Predicate to filter utxos
+     * @param excludeUtxos Utxos to exclude
+     * @return List of Utxos
+     * @throws ApiException
+     */
+    List<Utxo> findAll(String scriptAddress, Predicate<Utxo> predicate, Set<Utxo> excludeUtxos) throws ApiException;
+}

src/main/java/com/bloxbean/cardano/client/plutus/impl/DefaultScriptUtxoSelection.java

@@ -0,0 +1,96 @@
+package com.bloxbean.cardano.client.plutus.impl;
+
+import com.bloxbean.cardano.client.backend.api.UtxoService;
+import com.bloxbean.cardano.client.backend.common.OrderEnum;
+import com.bloxbean.cardano.client.backend.exception.ApiException;
+import com.bloxbean.cardano.client.backend.model.Result;
+import com.bloxbean.cardano.client.backend.model.Utxo;
+import com.bloxbean.cardano.client.plutus.api.ScriptUtxoSelection;
+
+import java.util.*;
+import java.util.function.Predicate;
+import java.util.stream.Collectors;
+
+//TODO -- Unit tests pending
+public class DefaultScriptUtxoSelection implements ScriptUtxoSelection {
+    private UtxoService utxoService;
+
+    public DefaultScriptUtxoSelection(UtxoService utxoService) {
+        this.utxoService = utxoService;
+    }
+
+    @Override
+    public Utxo findFirst(String scriptAddress, Predicate<Utxo> predicate) throws ApiException {
+        return findFirst(scriptAddress, predicate, Collections.EMPTY_SET);
+    }
+
+    @Override
+    public Utxo findFirst(String scriptAddress, Predicate<Utxo> predicate, Set<Utxo> excludeUtxos) throws ApiException {
+        boolean canContinue = true;
+        int i = 1;
+
+        while(canContinue) {
+            Result<List<Utxo>> result = utxoService.getUtxos(scriptAddress, getUtxoFetchSize(),
+                    i++, getUtxoFetchOrder());
+            if(result.code() == 200) {
+                List<Utxo> fetchData = result.getValue();
+
+                List<Utxo> data = (fetchData);
+                if(data == null || data.isEmpty())
+                    canContinue = false;
+
+                Optional<Utxo> option = data.stream().filter(predicate).findFirst();
+                if (option.isPresent())
+                    return option.get();
+
+            } else {
+                canContinue = false;
+                throw new ApiException(String.format("Unable to get enough Utxos for address : %s, reason: %s", scriptAddress, result.getResponse()));
+            }
+        }
+
+        return null;
+    }
+
+    @Override
+    public List<Utxo> findAll(String scriptAddress, Predicate<Utxo> predicate) throws ApiException {
+        return findAll(scriptAddress, predicate);
+    }
+
+    @Override
+    public List<Utxo> findAll(String scriptAddress, Predicate<Utxo> predicate, Set<Utxo> excludeUtxos) throws ApiException {
+        boolean canContinue = true;
+        int i = 1;
+
+        List<Utxo> utxoList = new ArrayList<>();
+        while(canContinue) {
+            Result<List<Utxo>> result = utxoService.getUtxos(scriptAddress, getUtxoFetchSize(),
+                    i++, getUtxoFetchOrder());
+            if(result.code() == 200) {
+                List<Utxo> fetchData = result.getValue();
+
+                List<Utxo> data = (fetchData);
+                if(data == null || data.isEmpty())
+                    canContinue = false;
+
+                List<Utxo> filterUtxos = data.stream().filter(predicate).collect(Collectors.toList());
+                utxoList.addAll(filterUtxos);
+
+            } else {
+                canContinue = false;
+                throw new ApiException(String.format("Unable to get enough Utxos for address : %s, reason: %s", scriptAddress, result.getResponse()));
+            }
+        }
+
+        return null;
+    }
+
+    private OrderEnum getUtxoFetchOrder() {
+        return OrderEnum.asc;
+    }
+
+    private int getUtxoFetchSize() {
+        return 100;
+    }
+
+}

src/main/java/com/bloxbean/cardano/client/transaction/spec/ConstrPlutusData.java

@@ -18,22 +18,30 @@
 @NoArgsConstructor
 @Builder
 public class ConstrPlutusData implements PlutusData {
-    private static final long GENERAL_FORM_TAG = 102;
-    private long tag;
+    private long alternative;
     private ListPlutusData data;
 
+    // see: https://github.com/input-output-hk/plutus/blob/1f31e640e8a258185db01fa899da63f9018c0e85/plutus-core/plutus-core/src/PlutusCore/Data.hs#L61
+    // We don't directly serialize the alternative in the tag, instead the scheme is:
+    // - Alternatives 0-6 -> tags 121-127, followed by the arguments in a list
+    // - Alternatives 7-127 -> tags 1280-1400, followed by the arguments in a list
+    // - Any alternatives, including those that don't fit in the above -> tag 102 followed by a list containing
+    //   an unsigned integer for the actual alternative, and then the arguments in a (nested!) list.
+    private static final long GENERAL_FORM_TAG = 102;
+
     @Override
     public DataItem serialize() throws CborSerializationException {
-        boolean isCompact = isTagCompact();
+        Long cborTag = alternativeToCompactCborTag(alternative);
         DataItem dataItem = null;
 
-        if (isCompact) {
+        if (cborTag != null) {
+            // compact form
             dataItem = data.serialize();
-            dataItem.setTag(tag);
+            dataItem.setTag(cborTag);
         } else {
             //general form
             Array constrArray = new Array();
-            constrArray.add(new UnsignedInteger(tag));
+            constrArray.add(new UnsignedInteger(alternative));
             constrArray.add(data.serialize());
             dataItem = constrArray;
             dataItem.setTag(GENERAL_FORM_TAG);
@@ -43,35 +51,46 @@ public DataItem serialize() throws CborSerializationException {
     }
 
     public static ConstrPlutusData deserialize(DataItem di) throws CborDeserializationException {
-        Tag diTag = di.getTag();
-        Long tag = null;
+        Tag tag = di.getTag();
+        Long alternative = null;
         ListPlutusData data = null;
 
-        if (GENERAL_FORM_TAG == diTag.getValue()) { //general form
+        if (GENERAL_FORM_TAG == tag.getValue()) { //general form
             Array constrArray = (Array) di;
             List<DataItem> dataItems = constrArray.getDataItems();
 
             if (dataItems.size() != 2)
                 throw new CborDeserializationException("Cbor deserialization failed. Expected 2 DataItem, found : " + dataItems.size());
 
-            tag = ((UnsignedInteger) dataItems.get(0)).getValue().longValue();
+            alternative = ((UnsignedInteger) dataItems.get(0)).getValue().longValue();
             data = ListPlutusData.deserialize((Array) dataItems.get(1));
 
         } else { //concise form
-            tag = diTag.getValue();
+            alternative = compactCborTagToAlternative(tag.getValue());
             data = ListPlutusData.deserialize((Array) di);
         }
 
         return ConstrPlutusData.builder()
-                .tag(tag)
+                .alternative(alternative)
                 .data(data)
                 .build();
     }
 
-    private boolean isTagCompact() {
-        if ((tag >= 121 && tag <= 127) || (tag >= 1280 && tag <= 1400))
-            return true;
-        else
-            return false;
+    private static Long alternativeToCompactCborTag(long alt) {
+        if (alt <= 6) {
+            return 121 + alt;
+        } else if (alt >= 7 && alt <= 127) {
+            return 1280 - 7 + alt;
+        } else
+            return null;
+    }
+
+    private static Long compactCborTagToAlternative(long cborTag) {
+        if (cborTag >= 121 && cborTag <= 127) {
+            return cborTag - 121;
+        } else if (cborTag >= 1280 && cborTag <= 1400) {
+            return cborTag - 1280 + 7;
+        } else
+            return null;
     }
 }

src/main/java/com/bloxbean/cardano/client/transaction/spec/ListPlutusData.java

@@ -2,6 +2,7 @@
 
 import co.nstant.in.cbor.model.Array;
 import co.nstant.in.cbor.model.DataItem;
+import co.nstant.in.cbor.model.Special;
 import com.bloxbean.cardano.client.exception.CborDeserializationException;
 import com.bloxbean.cardano.client.exception.CborSerializationException;
 import lombok.AllArgsConstructor;
@@ -32,6 +33,11 @@ public DataItem serialize() throws CborSerializationException {
             return null;
 
         Array plutusDataArray = new Array();
+
+        if (plutusDataList.size() == 0)
+            return plutusDataArray;
+
+        plutusDataArray.setChunked(true);
         for (PlutusData plutusData : plutusDataList) {
             DataItem di = plutusData.serialize();
             if (di == null) {
@@ -40,6 +46,7 @@ public DataItem serialize() throws CborSerializationException {
 
             plutusDataArray.add(di);
         }
+        plutusDataArray.add(Special.BREAK);
 
         return plutusDataArray;
     }
@@ -50,6 +57,8 @@ public static ListPlutusData deserialize(Array arrayDI) throws CborDeserializati
 
         ListPlutusData listPlutusData = new ListPlutusData();
         for (DataItem di : arrayDI.getDataItems()) {
+            if (di == Special.BREAK)
+                break;
             PlutusData plutusData = PlutusData.deserialize(di);
             if (plutusData == null)
                 throw new CborDeserializationException("Null value found during PlutusData de-serialization");

src/main/java/com/bloxbean/cardano/client/transaction/spec/PlutusData.java

@@ -18,6 +18,10 @@ public interface PlutusData {
 //            / big_int
 //  / bounded_bytes
 
+//    big_int = int / big_uint / big_nint ; New
+//    big_uint = #6.2(bounded_bytes) ; New
+//    big_nint = #6.3(bounded_bytes) ; New
+
     DataItem serialize() throws CborSerializationException;
 
     static PlutusData deserialize(DataItem dataItem) throws CborDeserializationException {
@@ -29,7 +33,11 @@ static PlutusData deserialize(DataItem dataItem) throws CborDeserializationExcep
         } else if (dataItem instanceof ByteString) {
             return BytesPlutusData.deserialize((ByteString) dataItem);
         } else if (dataItem instanceof Array) {
-            return ListPlutusData.deserialize((Array) dataItem);
+            if (dataItem.getTag() == null) {
+                return ListPlutusData.deserialize((Array) dataItem);
+            } else { //Tag found .. try Constr
+                return ConstrPlutusData.deserialize(dataItem);
+            }
         } else if (dataItem instanceof Map) {
             return MapPlutusData.deserialize((Map) dataItem);
         } else