feat: #411 tier ref script fee implementation for Conway era

backend/src/main/java/com/bloxbean/cardano/client/backend/api/DefaultScriptSupplier.java

@@ -0,0 +1,36 @@
+package com.bloxbean.cardano.client.backend.api;
+
+import com.bloxbean.cardano.client.api.ScriptSupplier;
+import com.bloxbean.cardano.client.api.exception.ApiException;
+import com.bloxbean.cardano.client.api.exception.ApiRuntimeException;
+import com.bloxbean.cardano.client.plutus.spec.PlutusScript;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+import java.util.Optional;
+
+public class DefaultScriptSupplier implements ScriptSupplier {
+    private final static Logger log = LoggerFactory.getLogger(DefaultScriptSupplier.class);
+
+    private ScriptService scriptService;
+
+    public DefaultScriptSupplier(ScriptService scriptService) {
+        this.scriptService = scriptService;
+    }
+
+    @Override
+    public Optional<PlutusScript> getScript(String scriptHash) {
+        try {
+            var result = scriptService.getPlutusScript(scriptHash);
+            if (result.isSuccessful())
+                return Optional.of(result.getValue());
+            else {
+                log.debug("Error fetching script for hash: {}, {}", scriptHash, result.getResponse());
+                return Optional.empty();
+            }
+        } catch (ApiException e) {
+            log.debug("Error fetching script for hash: {}", scriptHash, e);
+            throw new ApiRuntimeException(e);
+        }
+    }
+}

common/src/main/java/com/bloxbean/cardano/client/util/CheckedFunction.java

@@ -0,0 +1,13 @@
+package com.bloxbean.cardano.client.util;
+
+/**
+ * A functional interface that represents a function which may throw a checked exception.
+ * This is useful in scenarios where you want to use lambda expressions or method references
+ * that throw checked exceptions, particularly in stream operations or other functional contexts.
+ *
+ * @param <T> The type of the input to the function.
+ */
+@FunctionalInterface
+public interface CheckedFunction<T> {
+    T apply() throws Exception;
+}

common/src/main/java/com/bloxbean/cardano/client/util/Try.java

@@ -0,0 +1,70 @@
+package com.bloxbean.cardano.client.util;
+
+/**
+ * A utility class that encapsulates a computation that may either result in a successful value
+ * or throw an exception. This class provides a way to handle checked exceptions in a functional
+ * style, allowing the use of such methods in stream operations without needing to use try-catch blocks.
+ *
+ * @param <T> The type of the result of the computation.
+ */
+public class Try<T> {
+    private final T result;
+    private final Exception exception;
+
+    /**
+     * Private constructor to initialize a Try instance.
+     *
+     * @param result The result of the computation, or null if an exception occurred.
+     * @param exception The exception thrown by the computation, or null if the computation was successful.
+     */
+    private Try(T result, Exception exception) {
+        this.result = result;
+        this.exception = exception;
+    }
+
+    /**
+     * Executes the provided CheckedFunction, capturing any thrown exceptions.
+     *
+     * @param supplier A function that produces a result, potentially throwing an exception.
+     * @param <T> The type of the result produced by the function.
+     * @return A Try instance representing either a successful result or a captured exception.
+     */
+    public static <T> Try<T> of(CheckedFunction<T> supplier) {
+        try {
+            return new Try<>(supplier.apply(), null);
+        } catch (Exception e) {
+            return new Try<>(null, e);
+        }
+    }
+
+    /**
+     * Checks whether the computation was successful.
+     *
+     * @return true if the computation was successful (i.e., no exception was thrown), false otherwise.
+     */
+    public boolean isSuccess() {
+        return exception == null;
+    }
+
+    /**
+     * Returns the result of the computation, if it was successful.
+     *
+     * @return The result of the computation.
+     * @throws RuntimeException if the computation resulted in an exception.
+     */
+    public T get() {
+        if (exception != null) {
+            throw new RuntimeException(exception);
+        }
+        return result;
+    }
+
+    /**
+     * Returns the exception that was thrown during the computation, if any.
+     *
+     * @return The exception thrown by the computation, or null if the computation was successful.
+     */
+    public Exception getException() {
+        return exception;
+    }
+}

core-api/src/main/java/com/bloxbean/cardano/client/api/ScriptSupplier.java

@@ -2,10 +2,12 @@
 
 import com.bloxbean.cardano.client.plutus.spec.PlutusScript;
 
+import java.util.Optional;
+
 /**
  * Implement this interface to provide PlutusScript
  */
 @FunctionalInterface
 public interface ScriptSupplier {
-    PlutusScript getScript(String scriptHash);
+    Optional<PlutusScript> getScript(String scriptHash);
 }

core-api/src/main/java/com/bloxbean/cardano/client/api/model/ProtocolParams.java

@@ -92,5 +92,5 @@ public class ProtocolParams {
     private BigInteger govActionDeposit;
     private BigInteger drepDeposit;
     private Integer drepActivity;
-    private Integer minFeeRefScriptCostPerByte;
+    private BigDecimal minFeeRefScriptCostPerByte;
 }

core-api/src/main/java/com/bloxbean/cardano/client/api/model/ResultWrapper.java

@@ -0,0 +1,87 @@
+package com.bloxbean.cardano.client.api.model;
+
+import java.util.Optional;
+
+/**
+ * A generic wrapper class that encapsulates the result of an operation, which can either be a successful value or an error.
+ *
+ * <p>This class provides a way to handle operations that might return a result or throw an exception, without
+ * immediately throwing the exception. Instead, the result or error is stored in the `ResultWrapper`, allowing
+ * the caller to decide how to handle the success or failure.</p>
+ *
+ * @param <T> The type of the result value.
+ */
+public class ResultWrapper<T> {
+    private final Optional<T> value;
+    private final Exception error;
+
+    /**
+     * Private constructor to create a ResultWrapper instance.
+     *
+     * @param value the value of the result, wrapped in an Optional.
+     * @param error the exception that occurred, if any.
+     */
+    private ResultWrapper(Optional<T> value, Exception error) {
+        this.value = value;
+        this.error = error;
+    }
+
+    /**
+     * Creates a ResultWrapper representing a successful result.
+     *
+     * @param value the result value.
+     * @param <T> the type of the result.
+     * @return a ResultWrapper containing the result value.
+     */
+    public static <T> ResultWrapper<T> success(T value) {
+        return new ResultWrapper<>(Optional.ofNullable(value), null);
+    }
+
+    /**
+     * Creates a ResultWrapper representing a failure due to an exception.
+     *
+     * @param error the exception that occurred.
+     * @param <T> the type of the result that would have been returned on success.
+     * @return a ResultWrapper containing the exception.
+     */
+    public static <T> ResultWrapper<T> failure(Exception error) {
+        return new ResultWrapper<>(Optional.empty(), error);
+    }
+
+    /**
+     * Returns the result value, if present.
+     *
+     * @return an Optional containing the result value, or an empty Optional if the operation failed.
+     */
+    public Optional<T> getValue() {
+        return value;
+    }
+
+    /**
+     * Returns the exception that occurred, if any.
+     *
+     * @return an Optional containing the exception, or an empty Optional if the operation was successful.
+     */
+    public Optional<Exception> getError() {
+        return Optional.ofNullable(error);
+    }
+
+    /**
+     * Checks if the operation was successful.
+     *
+     * @return true if the result is present (indicating success), false otherwise.
+     */
+    public boolean isSuccess() {
+        return value.isPresent();
+    }
+
+    /**
+     * Checks if the operation resulted in a failure.
+     *
+     * @return true if an error occurred, false otherwise.
+     */
+    public boolean isFailure() {
+        return error != null;
+    }
+}
+

core-api/src/main/java/com/bloxbean/cardano/client/api/util/ReferenceScriptUtil.java

@@ -0,0 +1,33 @@
+package com.bloxbean.cardano.client.api.util;
+
+import com.bloxbean.cardano.client.api.ScriptSupplier;
+import com.bloxbean.cardano.client.api.UtxoSupplier;
+import com.bloxbean.cardano.client.util.Try;
+import com.bloxbean.cardano.client.transaction.spec.Transaction;
+
+import java.util.Optional;
+
+public class ReferenceScriptUtil {
+
+    /**
+     * Fetches the reference scripts from the utxo supplier and calculates the size of the reference scripts
+     *
+     * @param utxoSupplier utxo supplier
+     * @param scriptSupplier script supplier
+     * @param transaction transaction
+     * @return size of the reference scripts
+     */
+    public static long fetchAndCalculateReferenceScriptsSize(UtxoSupplier utxoSupplier, ScriptSupplier scriptSupplier, Transaction transaction) {
+        return transaction.getBody().getReferenceInputs()
+                .stream()
+                .flatMap(refInput -> utxoSupplier.getTxOutput(refInput.getTransactionId(), refInput.getIndex()).stream()
+                        .map(utxo -> scriptSupplier.getScript(utxo.getReferenceScriptHash()))
+                        .flatMap(Optional::stream))
+                .map(script -> Try.of(() -> script.scriptRefBytes().length))
+                .filter(Try::isSuccess)
+                .mapToLong(Try::get)
+                .sum();
+
+    }
+
+}