/*
 * 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.geode.management.internal.cli.converters;

import java.util.List;

import org.springframework.shell.core.Completion;
import org.springframework.shell.core.Converter;
import org.springframework.shell.core.MethodTarget;

/**
 * {@link Converter} for {@link Enum}.
 *
 * @since GemFire 7.0
 */
/*
 * Use this EnumConverter instead of SHL's EnumConverter. Added null check for existingData in
 * getAllPossibleValues
 * 
 * Original authors: Ben Alex & Alan Stewart
 */
@SuppressWarnings("all") // Enum parameter warning
public class EnumConverter implements Converter<Enum> {

  public Enum convertFromText(final String value, final Class<?> requiredType,
      final String optionContext) {
    Class<Enum> enumClass = (Class<Enum>) requiredType;
    return Enum.valueOf(enumClass, value);
  }

  public boolean getAllPossibleValues(final List<Completion> completions,
      final Class<?> requiredType, final String existingData, final String optionContext,
      final MethodTarget target) {
    Class<Enum> enumClass = (Class<Enum>) requiredType;
    for (Enum enumValue : enumClass.getEnumConstants()) {
      String candidate = enumValue.name();
      // GemFire/gfsh addition - check 'existingData == null'. GfshParser can
      // pass existingData as null
      if ("".equals(existingData) || existingData == null || candidate.startsWith(existingData)
          || existingData.startsWith(candidate)
          || candidate.toUpperCase().startsWith(existingData.toUpperCase())
          || existingData.toUpperCase().startsWith(candidate.toUpperCase())) {
        completions.add(new Completion(candidate));
      }
    }
    return true;
  }

  public boolean supports(final Class<?> requiredType, final String optionContext) {
    return Enum.class.isAssignableFrom(requiredType);
  }
}