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/*
 * Copyright 2014 the original author or authors
 *
 * Licensed 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 com.foreach.common.spring.enums;

import java.util.ArrayList;
import java.util.List;

/**
 * EnumUtils contains some utility routines to find specific enums if their classes
 * implement Idlookup or CodeLookup.
 */
public class EnumUtils
{
	protected EnumUtils() {
	}

	/**
	 * @param clazz an Enum class implementing IdLookup<I>
	 * @param id    an instance of type I
	 * @return the instance e of class clazz such that e.getId().equals( id )
	 */
	public static  & IdLookup> E getById( Class clazz, I id ) {
		for ( E e : clazz.getEnumConstants() ) {
			if ( e.getId().equals( id ) ) {
				return e;
			}
		}
		return null;
	}

	/**
	 * @param clazz an Enum class implementing CodeLookup<S>
	 * @param code  an instance of type S
	 * @return the instance e of class clazz such that e.getCode().equals( code ), unless S is String,
	 *         in which case equalsIgnoreCase is used instead of equals().
	 */
	public static  & CodeLookup> E getByCode( Class clazz, S code ) {
		if ( code instanceof String ) {
			return getByCaseInsensitiveString( clazz, code );
		}

		for ( E e : clazz.getEnumConstants() ) {
			if ( e.getCode().equals( code ) ) {
				return e;
			}
		}
		return null;
	}

	public static  & IdLookup> List getByIds( Class clazz, List ids ) {
		List result = new ArrayList();

		for ( I id : ids ) {
			E e = getById( clazz, id );
			if ( e != null ) {
				result.add( e );
			}
		}

		return result;
	}

	private static  & CodeLookup> E getByCaseInsensitiveString( Class clazz, S code ) {
		for ( E e : clazz.getEnumConstants() ) {
			if ( ( (String) e.getCode() ).equalsIgnoreCase( (String) code ) ) {
				return e;
			}
		}
		return null;
	}
}