/*
 *      Copyright (c) 2018-2028, DreamLu All rights reserved.
 *
 *  Redistribution and use in source and binary forms, with or without
 *  modification, are permitted provided that the following conditions are met:
 *
 *  Redistributions of source code must retain the above copyright notice,
 *  this list of conditions and the following disclaimer.
 *  Redistributions in binary form must reproduce the above copyright
 *  notice, this list of conditions and the following disclaimer in the
 *  documentation and/or other materials provided with the distribution.
 *  Neither the name of the dreamlu.net developer nor the names of its
 *  contributors may be used to endorse or promote products derived from
 *  this software without specific prior written permission.
 *  Author: DreamLu 卢春梦 ([email protected])
 */
package com.xkcoding.magic.core.tool.util;

import org.springframework.core.BridgeMethodResolver;
import org.springframework.core.DefaultParameterNameDiscoverer;
import org.springframework.core.MethodParameter;
import org.springframework.core.ParameterNameDiscoverer;
import org.springframework.core.annotation.AnnotatedElementUtils;
import org.springframework.core.annotation.SynthesizingMethodParameter;
import org.springframework.web.method.HandlerMethod;

import java.lang.annotation.Annotation;
import java.lang.reflect.Constructor;
import java.lang.reflect.Method;

/**
 * 类工具类
 *
 * @author L.cm
 */
public class ClassUtil extends org.springframework.util.ClassUtils {

	private static final ParameterNameDiscoverer PARAMETER_NAME_DISCOVERER = new DefaultParameterNameDiscoverer();

	/**
	 * 获取方法参数信息
	 *
	 * @param constructor    构造器
	 * @param parameterIndex 参数序号
	 * @return {MethodParameter}
	 */
	public static MethodParameter getMethodParameter(Constructor<?> constructor, int parameterIndex) {
		MethodParameter methodParameter = new SynthesizingMethodParameter(constructor, parameterIndex);
		methodParameter.initParameterNameDiscovery(PARAMETER_NAME_DISCOVERER);
		return methodParameter;
	}

	/**
	 * 获取方法参数信息
	 *
	 * @param method         方法
	 * @param parameterIndex 参数序号
	 * @return {MethodParameter}
	 */
	public static MethodParameter getMethodParameter(Method method, int parameterIndex) {
		MethodParameter methodParameter = new SynthesizingMethodParameter(method, parameterIndex);
		methodParameter.initParameterNameDiscovery(PARAMETER_NAME_DISCOVERER);
		return methodParameter;
	}

	/**
	 * 获取Annotation
	 *
	 * @param method         Method
	 * @param annotationType 注解类
	 * @param <A>            泛型标记
	 * @return {Annotation}
	 */
	public static <A extends Annotation> A getAnnotation(Method method, Class<A> annotationType) {
		Class<?> targetClass = method.getDeclaringClass();
		// The method may be on an interface, but we need attributes from the target class.
		// If the target class is null, the method will be unchanged.
		Method specificMethod = ClassUtil.getMostSpecificMethod(method, targetClass);
		// If we are dealing with method with generic parameters, find the original method.
		specificMethod = BridgeMethodResolver.findBridgedMethod(specificMethod);
		// 先找方法，再找方法上的类
		A annotation = AnnotatedElementUtils.findMergedAnnotation(specificMethod, annotationType);
		;
		if (null != annotation) {
			return annotation;
		}
		// 获取类上面的Annotation，可能包含组合注解，故采用spring的工具类
		return AnnotatedElementUtils.findMergedAnnotation(specificMethod.getDeclaringClass(), annotationType);
	}

	/**
	 * 获取Annotation
	 *
	 * @param handlerMethod  HandlerMethod
	 * @param annotationType 注解类
	 * @param <A>            泛型标记
	 * @return {Annotation}
	 */
	public static <A extends Annotation> A getAnnotation(HandlerMethod handlerMethod, Class<A> annotationType) {
		// 先找方法，再找方法上的类
		A annotation = handlerMethod.getMethodAnnotation(annotationType);
		if (null != annotation) {
			return annotation;
		}
		// 获取类上面的Annotation，可能包含组合注解，故采用spring的工具类
		Class<?> beanType = handlerMethod.getBeanType();
		return AnnotatedElementUtils.findMergedAnnotation(beanType, annotationType);
	}

}