/**
    * Copyright 2010-2012 The Kuali Foundation
    *
    * Licensed under the Educational Community 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.opensource.org/licenses/ecl2.php
    *
   * 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.kuali.common.util;
  
  import org.apache.commons.lang3.StringUtils;
  
  public class VersionUtils {
  
  	public static final String MAVEN_SNAPSHOT_TOKEN = "SNAPSHOT";
  	private static final String[] DELIMITERS = new String[] { ".", "-" };
  	private static final String SEPARATOR_CHARS = Str.toString(DELIMITERS);
  
  	/**
  	 * Return true if <code>version</code> ends with <code>-SNAPSHOT</code> or <code>.SNAPSHOT</code> (case insensitive).
  	 */
  	public static final boolean isSnapshot(String version) {
  		for (String delimiter : DELIMITERS) {
  			String suffix = delimiter + MAVEN_SNAPSHOT_TOKEN;
  			if (StringUtils.endsWithIgnoreCase(version, suffix)) {
  				return true;
  			}
  		}
  		return false;
  	}
  
  	/**
  	 * Return <code>version</code> with <code>.SNAPSHOT</code> or <code>-SNAPSHOT</code> removed from the end (if present)
  	 *
  	 * <pre>
  	 * 1.0.0-SNAPSHOT returns 1.0.0
  	 * 1.0.0.SNAPSHOT returns 1.0.0
  	 * 1.0.0          returns 1.0.0
  	 * 1.0.0SNAPSHOT  returns 1.0.0SNAPSHOT
  	 * </pre>
  	 */
  	public static final String trimSnapshot(String version) {
  		if (isSnapshot(version)) {
  			int length = MAVEN_SNAPSHOT_TOKEN.length() + 1;
  			return StringUtils.left(version, version.length() - length);
  		} else {
  			return version;
  		}
  	}
  
  	/**
  	 * Parse a <code>Version</code> object from the <code>version</code> string. The logic here is crudely simple. First
  	 * <code>SNAPSHOT</code> is trimmed off the end of the string (if it exists). Whatever remains is then split into tokens using
  	 * <code>.</code> and <code>-</code> as delimiters. The first 3 tokens encountered are <code>major</code>, <code>minor</code>, and
  	 * <code>incremental</code>, respectively. Anything after that is the <code>qualifier</code>
  	 */
  	public static final Version getVersion(String version) {
  		boolean snapshot = isSnapshot(version);
  		String trimmed = trimSnapshot(version);
  		Version v = new Version();
  		v.setTrimmed(trimmed);
  		v.setSnapshot(snapshot);
  		String[] tokens = StringUtils.split(trimmed, SEPARATOR_CHARS);
  		if (tokens.length > 0) {
  			v.setMajor(tokens[0]);
  		}
  		if (tokens.length > 1) {
  			v.setMinor(tokens[1]);
  		}
  		if (tokens.length > 2) {
  			v.setIncremental(tokens[2]);
  		}
  		String qualifier = getQualifier(trimmed, tokens);
  		v.setQualifier(qualifier);
  		return v;
  	}
  
  	protected static final String getQualifier(String trimmed, String[] tokens) {
  		if (tokens.length < 4) {
  			return null;
  		}
  		int pos = tokens[0].length() + 1 + tokens[1].length() + 1 + tokens[2].length() + 1;
  		return trimmed.substring(pos);
  	}
  
  }