/*
    * Licensed to the Apache Software Foundation (ASF) under one or more
    * contributor license agreements.  See the NOTICE file distributed with
    * this work for additional information regarding copyright ownership.
    * The ASF licenses this file to You under the Apache License, Version 2.0
    * (the "License"); you may not use this file except in compliance with
    * the License.  You may obtain a copy of the License at
    *
    *      http://www.apache.org/licenses/LICENSE-2.0
   *
   * Unless required by applicable law or agreed to in writing, software
   * distributed under the License is distributed on an "AS IS" BASIS,
   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
   * See the License for the specific language governing permissions and
   * limitations under the License.
   */
  
  package org.apache.commons.lang3.function;
  
  import java.io.IOException;
  import java.io.UncheckedIOException;
  import java.lang.reflect.UndeclaredThrowableException;
  import java.util.Collection;
  import java.util.Objects;
  import java.util.concurrent.Callable;
  import java.util.function.BiConsumer;
  import java.util.function.BiFunction;
  import java.util.function.BiPredicate;
  import java.util.function.Consumer;
  import java.util.function.Function;
  import java.util.function.Predicate;
  import java.util.function.Supplier;
  import java.util.stream.Stream;
  
  import org.apache.commons.lang3.exception.ExceptionUtils;
  import org.apache.commons.lang3.stream.Streams;
  import org.apache.commons.lang3.stream.Streams.FailableStream;
  
  /**
   * This class provides utility functions, and classes for working with the {@code java.util.function} package, or more
   * generally, with Java 8 lambdas. More specifically, it attempts to address the fact that lambdas are supposed not to
   * throw Exceptions, at least not checked Exceptions, AKA instances of {@link Exception}. This enforces the use of
   * constructs like:
   *
   * <pre>
   * Consumer&lt;java.lang.reflect.Method&gt; consumer = m -&gt; {
   *     try {
   *         m.invoke(o, args);
   *     } catch (Throwable t) {
   *         throw Failable.rethrow(t);
   *     }
   * };
   * </pre>
   *
   * <p>
   * By replacing a {@link java.util.function.Consumer Consumer&lt;O&gt;} with a {@link FailableConsumer
   * FailableConsumer&lt;O,? extends Throwable&gt;}, this can be written like follows:
   * </p>
   *
   * <pre>
   * Functions.accept((m) -&gt; m.invoke(o, args));
   * </pre>
   *
   * <p>
   * Obviously, the second version is much more concise and the spirit of Lambda expressions is met better than the second
   * version.
   * </p>
   *
   * @since 3.11
   */
  public class Failable {
  
      /**
       * Consumes a consumer and rethrows any exception as a {@link RuntimeException}.
       *
       * @param consumer the consumer to consume
       * @param object1 the first object to consume by {@code consumer}
       * @param object2 the second object to consume by {@code consumer}
       * @param <T> the type of the first argument the consumer accepts
       * @param <U> the type of the second argument the consumer accepts
       * @param <E> the type of checked exception the consumer may throw
       */
      public static <T, U, E extends Throwable> void accept(final FailableBiConsumer<T, U, E> consumer, final T object1,
          final U object2) {
          run(() -> consumer.accept(object1, object2));
      }
  
      /**
       * Consumes a consumer and rethrows any exception as a {@link RuntimeException}.
       *
       * @param consumer the consumer to consume
       * @param object the object to consume by {@code consumer}
       * @param <T> the type the consumer accepts
       * @param <E> the type of checked exception the consumer may throw
       */
      public static <T, E extends Throwable> void accept(final FailableConsumer<T, E> consumer, final T object) {
          run(() -> consumer.accept(object));
      }
  
     /**
      * Consumes a consumer and rethrows any exception as a {@link RuntimeException}.
      *
      * @param consumer the consumer to consume
      * @param value the value to consume by {@code consumer}
      * @param <E> the type of checked exception the consumer may throw
      */
     public static <E extends Throwable> void accept(final FailableDoubleConsumer<E> consumer, final double value) {
         run(() -> consumer.accept(value));
     }
 
     /**
      * Consumes a consumer and rethrows any exception as a {@link RuntimeException}.
      *
      * @param consumer the consumer to consume
      * @param value the value to consume by {@code consumer}
      * @param <E> the type of checked exception the consumer may throw
      */
     public static <E extends Throwable> void accept(final FailableIntConsumer<E> consumer, final int value) {
         run(() -> consumer.accept(value));
     }
 
     /**
      * Consumes a consumer and rethrows any exception as a {@link RuntimeException}.
      *
      * @param consumer the consumer to consume
      * @param value the value to consume by {@code consumer}
      * @param <E> the type of checked exception the consumer may throw
      */
     public static <E extends Throwable> void accept(final FailableLongConsumer<E> consumer, final long value) {
         run(() -> consumer.accept(value));
     }
 
     /**
      * Applies a function and rethrows any exception as a {@link RuntimeException}.
      *
      * @param function the function to apply
      * @param input1 the first input to apply {@code function} on
      * @param input2 the second input to apply {@code function} on
      * @param <T> the type of the first argument the function accepts
      * @param <U> the type of the second argument the function accepts
      * @param <R> the return type of the function
      * @param <E> the type of checked exception the function may throw
      * @return the value returned from the function
      */
     public static <T, U, R, E extends Throwable> R apply(final FailableBiFunction<T, U, R, E> function, final T input1,
         final U input2) {
         return get(() -> function.apply(input1, input2));
     }
 
     /**
      * Applies a function and rethrows any exception as a {@link RuntimeException}.
      *
      * @param function the function to apply
      * @param input the input to apply {@code function} on
      * @param <T> the type of the argument the function accepts
      * @param <R> the return type of the function
      * @param <E> the type of checked exception the function may throw
      * @return the value returned from the function
      */
     public static <T, R, E extends Throwable> R apply(final FailableFunction<T, R, E> function, final T input) {
         return get(() -> function.apply(input));
     }
 
     /**
      * Applies a function and rethrows any exception as a {@link RuntimeException}.
      *
      * @param function the function to apply
      * @param left the first input to apply {@code function} on
      * @param right the second input to apply {@code function} on
      * @param <E> the type of checked exception the function may throw
      * @return the value returned from the function
      */
     public static <E extends Throwable> double applyAsDouble(final FailableDoubleBinaryOperator<E> function,
         final double left, final double right) {
         return getAsDouble(() -> function.applyAsDouble(left, right));
     }
 
     /**
      * Converts the given {@link FailableBiConsumer} into a standard {@link BiConsumer}.
      *
      * @param <T> the type of the first argument of the consumers
      * @param <U> the type of the second argument of the consumers
      * @param consumer a failable {@link BiConsumer}
      * @return a standard {@link BiConsumer}
      */
     public static <T, U> BiConsumer<T, U> asBiConsumer(final FailableBiConsumer<T, U, ?> consumer) {
         return (input1, input2) -> accept(consumer, input1, input2);
     }
 
     /**
      * Converts the given {@link FailableBiFunction} into a standard {@link BiFunction}.
      *
      * @param <T> the type of the first argument of the input of the functions
      * @param <U> the type of the second argument of the input of the functions
      * @param <R> the type of the output of the functions
      * @param function a {@link FailableBiFunction}
      * @return a standard {@link BiFunction}
      */
     public static <T, U, R> BiFunction<T, U, R> asBiFunction(final FailableBiFunction<T, U, R, ?> function) {
         return (input1, input2) -> apply(function, input1, input2);
     }
 
     /**
      * Converts the given {@link FailableBiPredicate} into a standard {@link BiPredicate}.
      *
      * @param <T> the type of the first argument used by the predicates
      * @param <U> the type of the second argument used by the predicates
      * @param predicate a {@link FailableBiPredicate}
      * @return a standard {@link BiPredicate}
      */
     public static <T, U> BiPredicate<T, U> asBiPredicate(final FailableBiPredicate<T, U, ?> predicate) {
         return (input1, input2) -> test(predicate, input1, input2);
     }
 
     /**
      * Converts the given {@link FailableCallable} into a standard {@link Callable}.
      *
      * @param <V> the type used by the callables
      * @param callable a {@link FailableCallable}
      * @return a standard {@link Callable}
      */
     public static <V> Callable<V> asCallable(final FailableCallable<V, ?> callable) {
         return () -> call(callable);
     }
 
     /**
      * Converts the given {@link FailableConsumer} into a standard {@link Consumer}.
      *
      * @param <T> the type used by the consumers
      * @param consumer a {@link FailableConsumer}
      * @return a standard {@link Consumer}
      */
     public static <T> Consumer<T> asConsumer(final FailableConsumer<T, ?> consumer) {
         return input -> accept(consumer, input);
     }
 
     /**
      * Converts the given {@link FailableFunction} into a standard {@link Function}.
      *
      * @param <T> the type of the input of the functions
      * @param <R> the type of the output of the functions
      * @param function a {code FailableFunction}
      * @return a standard {@link Function}
      */
     public static <T, R> Function<T, R> asFunction(final FailableFunction<T, R, ?> function) {
         return input -> apply(function, input);
     }
 
     /**
      * Converts the given {@link FailablePredicate} into a standard {@link Predicate}.
      *
      * @param <T> the type used by the predicates
      * @param predicate a {@link FailablePredicate}
      * @return a standard {@link Predicate}
      */
     public static <T> Predicate<T> asPredicate(final FailablePredicate<T, ?> predicate) {
         return input -> test(predicate, input);
     }
 
     /**
      * Converts the given {@link FailableRunnable} into a standard {@link Runnable}.
      *
      * @param runnable a {@link FailableRunnable}
      * @return a standard {@link Runnable}
      */
     public static Runnable asRunnable(final FailableRunnable<?> runnable) {
         return () -> run(runnable);
     }
 
     /**
      * Converts the given {@link FailableSupplier} into a standard {@link Supplier}.
      *
      * @param <T> the type supplied by the suppliers
      * @param supplier a {@link FailableSupplier}
      * @return a standard {@link Supplier}
      */
     public static <T> Supplier<T> asSupplier(final FailableSupplier<T, ?> supplier) {
         return () -> get(supplier);
     }
 
     /**
      * Calls a callable and rethrows any exception as a {@link RuntimeException}.
      *
      * @param callable the callable to call
      * @param <V> the return type of the callable
      * @param <E> the type of checked exception the callable may throw
      * @return the value returned from the callable
      */
     public static <V, E extends Throwable> V call(final FailableCallable<V, E> callable) {
         return get(callable::call);
     }
 
     /**
      * Invokes a supplier, and returns the result.
      *
      * @param supplier The supplier to invoke.
      * @param <T> The suppliers output type.
      * @param <E> The type of checked exception, which the supplier can throw.
      * @return The object, which has been created by the supplier
      */
     public static <T, E extends Throwable> T get(final FailableSupplier<T, E> supplier) {
         try {
             return supplier.get();
         } catch (final Throwable t) {
             throw rethrow(t);
         }
     }
 
     /**
      * Invokes a boolean supplier, and returns the result.
      *
      * @param supplier The boolean supplier to invoke.
      * @param <E> The type of checked exception, which the supplier can throw.
      * @return The boolean, which has been created by the supplier
      */
     public static <E extends Throwable> boolean getAsBoolean(final FailableBooleanSupplier<E> supplier) {
         try {
             return supplier.getAsBoolean();
         } catch (final Throwable t) {
             throw rethrow(t);
         }
     }
 
     /**
      * Invokes a double supplier, and returns the result.
      *
      * @param supplier The double supplier to invoke.
      * @param <E> The type of checked exception, which the supplier can throw.
      * @return The double, which has been created by the supplier
      */
     public static <E extends Throwable> double getAsDouble(final FailableDoubleSupplier<E> supplier) {
         try {
             return supplier.getAsDouble();
         } catch (final Throwable t) {
             throw rethrow(t);
         }
     }
 
     /**
      * Invokes an int supplier, and returns the result.
      *
      * @param supplier The int supplier to invoke.
      * @param <E> The type of checked exception, which the supplier can throw.
      * @return The int, which has been created by the supplier
      */
     public static <E extends Throwable> int getAsInt(final FailableIntSupplier<E> supplier) {
         try {
             return supplier.getAsInt();
         } catch (final Throwable t) {
             throw rethrow(t);
         }
     }
 
     /**
      * Invokes a long supplier, and returns the result.
      *
      * @param supplier The long supplier to invoke.
      * @param <E> The type of checked exception, which the supplier can throw.
      * @return The long, which has been created by the supplier
      */
     public static <E extends Throwable> long getAsLong(final FailableLongSupplier<E> supplier) {
         try {
             return supplier.getAsLong();
         } catch (final Throwable t) {
             throw rethrow(t);
         }
     }
 
     /**
      * Invokes a short supplier, and returns the result.
      *
      * @param supplier The short supplier to invoke.
      * @param <E> The type of checked exception, which the supplier can throw.
      * @return The short, which has been created by the supplier
      */
     public static <E extends Throwable> short getAsShort(final FailableShortSupplier<E> supplier) {
         try {
             return supplier.getAsShort();
         } catch (final Throwable t) {
             throw rethrow(t);
         }
     }
 
     /**
      * Rethrows a {@link Throwable} as an unchecked exception. If the argument is already unchecked, namely a
      * {@link RuntimeException} or {@link Error} then the argument will be rethrown without modification. If the
      * exception is {@link IOException} then it will be wrapped into a {@link UncheckedIOException}. In every other
      * cases the exception will be wrapped into a {@code
      * UndeclaredThrowableException}
      *
      * <p>
      * Note that there is a declared return type for this method, even though it never returns. The reason for that is
      * to support the usual pattern:
      * </p>
      *
      * <pre>
      * throw rethrow(myUncheckedException);
      * </pre>
      *
      * <p>
      * instead of just calling the method. This pattern may help the Java compiler to recognize that at that point an
      * exception will be thrown and the code flow analysis will not demand otherwise mandatory commands that could
      * follow the method call, like a {@code return} statement from a value returning method.
      * </p>
      *
      * @param throwable The throwable to rethrow possibly wrapped into an unchecked exception
      * @return Never returns anything, this method never terminates normally.
      */
     public static RuntimeException rethrow(final Throwable throwable) {
         Objects.requireNonNull(throwable, "throwable");
         ExceptionUtils.throwUnchecked(throwable);
         if (throwable instanceof IOException) {
             throw new UncheckedIOException((IOException) throwable);
         }
         throw new UndeclaredThrowableException(throwable);
     }
 
     /**
      * Runs a runnable and rethrows any exception as a {@link RuntimeException}.
      *
      * @param runnable The runnable to run
      * @param <E> the type of checked exception the runnable may throw
      */
     public static <E extends Throwable> void run(final FailableRunnable<E> runnable) {
         try {
             runnable.run();
         } catch (final Throwable t) {
             throw rethrow(t);
         }
     }
 
     /**
      * Converts the given collection into a {@link FailableStream}. The {@link FailableStream} consists of the
      * collections elements. Shortcut for
      *
      * <pre>
      * Functions.stream(collection.stream());
      * </pre>
      *
      * @param collection The collection, which is being converted into a {@link FailableStream}.
      * @param <E> The collections element type. (In turn, the result streams element type.)
      * @return The created {@link FailableStream}.
      */
     public static <E> FailableStream<E> stream(final Collection<E> collection) {
         return new FailableStream<>(collection.stream());
     }
 
     /**
      * Converts the given stream into a {@link FailableStream}. The {@link FailableStream} consists of the same
      * elements, than the input stream. However, failable lambdas, like {@link FailablePredicate},
      * {@link FailableFunction}, and {@link FailableConsumer} may be applied, rather than {@link Predicate},
      * {@link Function}, {@link Consumer}, etc.
      *
      * @param stream The stream, which is being converted into a {@link FailableStream}.
      * @param <T> The streams element type.
      * @return The created {@link FailableStream}.
      */
     public static <T> FailableStream<T> stream(final Stream<T> stream) {
         return new FailableStream<>(stream);
     }
 
     /**
      * Tests a predicate and rethrows any exception as a {@link RuntimeException}.
      *
      * @param predicate the predicate to test
      * @param object1 the first input to test by {@code predicate}
      * @param object2 the second input to test by {@code predicate}
      * @param <T> the type of the first argument the predicate tests
      * @param <U> the type of the second argument the predicate tests
      * @param <E> the type of checked exception the predicate may throw
      * @return the boolean value returned by the predicate
      */
     public static <T, U, E extends Throwable> boolean test(final FailableBiPredicate<T, U, E> predicate,
         final T object1, final U object2) {
         return getAsBoolean(() -> predicate.test(object1, object2));
     }
 
     /**
      * Tests a predicate and rethrows any exception as a {@link RuntimeException}.
      *
      * @param predicate the predicate to test
      * @param object the input to test by {@code predicate}
      * @param <T> the type of argument the predicate tests
      * @param <E> the type of checked exception the predicate may throw
      * @return the boolean value returned by the predicate
      */
     public static <T, E extends Throwable> boolean test(final FailablePredicate<T, E> predicate, final T object) {
         return getAsBoolean(() -> predicate.test(object));
     }
 
     /**
      * A simple try-with-resources implementation, that can be used, if your objects do not implement the
      * {@link AutoCloseable} interface. The method executes the {@code action}. The method guarantees, that <em>all</em>
      * the {@code resources} are being executed, in the given order, afterwards, and regardless of success, or failure.
      * If either the original action, or any of the resource action fails, then the <em>first</em> failure (AKA
      * {@link Throwable}) is rethrown. Example use:
      *
      * <pre>
      * final FileInputStream fis = new FileInputStream("my.file");
      * Functions.tryWithResources(useInputStream(fis), null, () -&gt; fis.close());
      * </pre>
      *
      * @param action The action to execute. This object <em>will</em> always be invoked.
      * @param errorHandler An optional error handler, which will be invoked finally, if any error occurred. The error
      *        handler will receive the first error, AKA {@link Throwable}.
      * @param resources The resource actions to execute. <em>All</em> resource actions will be invoked, in the given
      *        order. A resource action is an instance of {@link FailableRunnable}, which will be executed.
      * @see #tryWithResources(FailableRunnable, FailableRunnable...)
      */
     @SafeVarargs
     public static void tryWithResources(final FailableRunnable<? extends Throwable> action,
         final FailableConsumer<Throwable, ? extends Throwable> errorHandler,
         final FailableRunnable<? extends Throwable>... resources) {
         final FailableConsumer<Throwable, ? extends Throwable> actualErrorHandler;
         if (errorHandler == null) {
             actualErrorHandler = Failable::rethrow;
         } else {
             actualErrorHandler = errorHandler;
         }
         Streams.of(resources).forEach(r -> Objects.requireNonNull(r, "runnable"));
         Throwable th = null;
         try {
             action.run();
         } catch (final Throwable t) {
             th = t;
         }
         if (resources != null) {
             for (final FailableRunnable<?> runnable : resources) {
                 try {
                     runnable.run();
                 } catch (final Throwable t) {
                     if (th == null) {
                         th = t;
                     }
                 }
             }
         }
         if (th != null) {
             try {
                 actualErrorHandler.accept(th);
             } catch (final Throwable t) {
                 throw rethrow(t);
             }
         }
     }
 
     /**
      * A simple try-with-resources implementation, that can be used, if your objects do not implement the
      * {@link AutoCloseable} interface. The method executes the {@code action}. The method guarantees, that <em>all</em>
      * the {@code resources} are being executed, in the given order, afterwards, and regardless of success, or failure.
      * If either the original action, or any of the resource action fails, then the <em>first</em> failure (AKA
      * {@link Throwable}) is rethrown. Example use:
      *
      * <pre>
      * final FileInputStream fis = new FileInputStream("my.file");
      * Functions.tryWithResources(useInputStream(fis), () -&gt; fis.close());
      * </pre>
      *
      * @param action The action to execute. This object <em>will</em> always be invoked.
      * @param resources The resource actions to execute. <em>All</em> resource actions will be invoked, in the given
      *        order. A resource action is an instance of {@link FailableRunnable}, which will be executed.
      * @see #tryWithResources(FailableRunnable, FailableConsumer, FailableRunnable...)
      */
     @SafeVarargs
     public static void tryWithResources(final FailableRunnable<? extends Throwable> action,
         final FailableRunnable<? extends Throwable>... resources) {
         tryWithResources(action, null, resources);
     }
 
     private Failable() {
         // empty
     }
 
 }