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/* 
 * Copyright (C) 2018 V12 Technology Ltd.
 *
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the Server Side Public License, version 1,
 * as published by MongoDB, Inc.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * Server Side Public License for more details.
 *
 * You should have received a copy of the Server Side Public License
 * along with this program.  If not, see 
 * .
 */
package com.fluxtion.api.partition;

import java.io.Serializable;
import java.lang.invoke.SerializedLambda;
import java.lang.reflect.Method;
import static java.util.Arrays.asList;
import java.util.Objects;
import java.util.function.BiConsumer;
import java.util.function.BiFunction;
import java.util.function.Consumer;
import java.util.function.Function;
import java.util.function.Supplier;

/**
 *
 * @author Greg Higgins
 */
public interface LambdaReflection {

    interface MethodReferenceReflection {

        //inspired by: http://benjiweber.co.uk/blog/2015/08/17/lambda-parameter-names-with-reflection/
        default SerializedLambda serialized() {
            try {
                Method replaceMethod = getClass().getDeclaredMethod("writeReplace");
                replaceMethod.setAccessible(true);
                return (SerializedLambda) replaceMethod.invoke(this);
            } catch (Exception e) {
                throw new RuntimeException(e);
            }
        }
        
        default Class getContainingClass(ClassLoader loader) {
            try {
                String className = serialized().getImplClass().replaceAll("/", ".");
                return Class.forName(className, true,  loader);
            } catch (Exception e) {
                throw new RuntimeException(e);
            }
        }
        
        default Class getContainingClass() {
            try {
                String className = serialized().getImplClass().replaceAll("/", ".");
                return Class.forName(className );
            } catch (Exception e) {
                throw new RuntimeException(e);
            }
        }

        default Object[] captured() {
            final SerializedLambda serialized = serialized();
            Object[] args = new Object[serialized.getCapturedArgCount()];
            for (int i = 0; i < serialized.getCapturedArgCount(); i++) {
                args[i] = serialized.getCapturedArg(i);
            }
            return args;
        }
        
        default Method method(ClassLoader loader) {
            SerializedLambda lambda = serialized();
            Class containingClass = getContainingClass(loader);
            return asList(containingClass.getDeclaredMethods())
                    .stream()
                    .filter(method -> Objects.equals(method.getName(), lambda.getImplMethodName()))
                    .findFirst()
                    .orElseThrow(UnableToGuessMethodException::new);
        }
        
        default Method method() {
            SerializedLambda lambda = serialized();
            Class containingClass = getContainingClass();
            return asList(containingClass.getDeclaredMethods())
                    .stream()
                    .filter(method -> Objects.equals(method.getName(), lambda.getImplMethodName()))
                    .findFirst()
                    .orElseThrow(UnableToGuessMethodException::new);
        }

        class UnableToGuessMethodException extends RuntimeException {
        }
    }

    interface SerializableSupplier extends Supplier, Serializable, MethodReferenceReflection {
    }

    interface SerializableConsumer extends Consumer, Serializable, MethodReferenceReflection {
    }

    interface SerializableBiConsumer extends BiConsumer, Serializable, MethodReferenceReflection {
    }

    interface SerializableFunction extends Function, Serializable, MethodReferenceReflection {
    }

    interface SerializableBiFunction extends BiFunction, Serializable, MethodReferenceReflection {
    }

    interface SerializableTriFunction extends TriFunction, Serializable, MethodReferenceReflection {
    }

    interface SerializableQuadFunction extends QuadFunction, Serializable, MethodReferenceReflection {
    }

    @FunctionalInterface
    interface TriFunction {
        R apply(F f, T t, U u);
    }
    @FunctionalInterface
    interface QuadFunction {
        R apply(F f, T t, U u, V v);
    }

}