/*
 * 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.solr.client.solrj.util;

import java.util.Locale;
import java.util.regex.Pattern;

import org.apache.solr.common.SolrException;

/**
 * Ensures that provided identifiers align with Solr's recommendations/requirements for choosing
 * collection, core, etc identifiers.
 *  
 * Identifiers are allowed to contain underscores, periods, hyphens, and alphanumeric characters.
 */
public class SolrIdentifierValidator {
  final static Pattern identifierPattern = Pattern.compile("^(?!\\-)[\\._A-Za-z0-9\\-]+$");

  public enum IdentifierType {
    SHARD, COLLECTION, CORE, ALIAS
  }

  public static String validateName(IdentifierType type, String name) {
    if (!validateIdentifier(name))
      throw new SolrException(SolrException.ErrorCode.BAD_REQUEST, getIdentifierMessage(type, name));
    return name;
  }

  public static String validateShardName(String shardName) {
    return validateName(IdentifierType.SHARD, shardName);
  }
  
  public static String validateCollectionName(String collectionName) {
    return validateName(IdentifierType.COLLECTION, collectionName);
  }

  public static String validateAliasName(String alias) {
    return validateName(IdentifierType.ALIAS, alias);
  }

  public static String validateCoreName(String coreName) {
    return validateName(IdentifierType.CORE, coreName);
  }

  private static boolean validateIdentifier(String identifier) {
    if (identifier == null || ! identifierPattern.matcher(identifier).matches()) {
      return false;
    }
    return true;
  }

  public static String getIdentifierMessage(IdentifierType identifierType, String name) {
      String typeStr = identifierType.toString().toLowerCase(Locale.ROOT);
    return "Invalid " + typeStr + ": [" + name + "]. " + typeStr + " names must consist entirely of periods, "
        + "underscores, hyphens, and alphanumerics as well not start with a hyphen";
  }

}