/*
    * REPOWEB, repository manager.
    *
    * Terms of license - http://opensource.org/licenses/apachepl.php
    */
   /* Derived from Ant source. */
   package org.repoweb.model.file.util;
   import java.io.File;
   import java.util.ArrayList;
  import java.util.List;
  import java.util.StringTokenizer;
  
  /***
   * <p>This is a utility class used by selectors and DirectoryScanner. The
   * functionality more properly belongs just to selectors, but unfortunately
   * DirectoryScanner exposed these as protected methods. Thus we have to
   * support any subclasses of DirectoryScanner that may access these methods.
   * </p>
   * <p>This is a Singleton.</p>
   *
   * @author Arnout J. Kuiper
   * <a href="mailto:ajkuiper@wxs.nl">ajkuiper@wxs.nl</a>
   * @author Magesh Umasankar
   * @author <a href="mailto:bruce@callenish.com">Bruce Atherton</a>
   * @since 1.5
   */
  final class SelectorUtils {
      /***
       * Private Constructor.
       */
      private SelectorUtils() {}
  
      /***
       * Tests whether or not a given path matches the start of a given
       * pattern up to the first "**".
       * <p>
       * This is not a general purpose test and should only be used if you
       * can live with false positives. For example, <code>pattern=**\a</code>
       * and <code>str=b</code> will yield <code>true</code>.
       *
       * @param pattern The pattern to match against. Must not be
       *                <code>null</code>.
       * @param str     The path to match, as a String. Must not be
       *                <code>null</code>.
       * @param isCaseSensitive Whether or not matching should be performed
       *                        case sensitively.
       *
       * @return whether or not a given path matches the start of a given
       * pattern up to the first "**".
       */
      public static boolean matchPatternStart(String pattern, String str,
          boolean isCaseSensitive) {
          // When str starts with a File.separator, pattern has to start with a
          // File.separator.
          // When pattern starts with a File.separator, str has to start with a
          // File.separator.
          if (str.startsWith(File.separator) != pattern.startsWith(File.separator)) {
              return false;
          }
  
          List patDirs = tokenizePath(pattern);
          List strDirs = tokenizePath(str);
  
          int patIdxStart = 0;
          int patIdxEnd = patDirs.size() - 1;
          int strIdxStart = 0;
          int strIdxEnd = strDirs.size() - 1;
  
          // up to first '**'
          while (patIdxStart <= patIdxEnd && strIdxStart <= strIdxEnd) {
              String patDir = (String)patDirs.get(patIdxStart);
              if (patDir.equals("**")) {
                  break;
              }
              if (!match(patDir, (String)strDirs.get(strIdxStart), isCaseSensitive)) {
                  return false;
              }
              patIdxStart++;
              strIdxStart++;
          }
  
          if (strIdxStart > strIdxEnd) {
              // String is exhausted
              return true;
          }
          else if (patIdxStart > patIdxEnd) {
              // String not exhausted, but pattern is. Failure.
              return false;
          }
          else {
              // pattern now holds ** while string is not exhausted
              // this will generate false positives but we can live with that.
              return true;
          }
      }
  
  
      /***
       * Tests whether or not a given path matches a given pattern.
      *
      * @param pattern The pattern to match against. Must not be
      *                <code>null</code>.
      * @param str     The path to match, as a String. Must not be
      *                <code>null</code>.
      * @param isCaseSensitive Whether or not matching should be performed
      *                        case sensitively.
      *
      * @return <code>true</code> if the pattern matches against the string,
      *         or <code>false</code> otherwise.
      */
     public static boolean matchPath(String pattern, String str, boolean isCaseSensitive) {
         // When str starts with a File.separator, pattern has to start with a
         // File.separator.
         // When pattern starts with a File.separator, str has to start with a
         // File.separator.
         if (str.startsWith(File.separator) != pattern.startsWith(File.separator)) {
             return false;
         }
 
         List patDirs = tokenizePath(pattern);
         List strDirs = tokenizePath(str);
 
         int patIdxStart = 0;
         int patIdxEnd = patDirs.size() - 1;
         int strIdxStart = 0;
         int strIdxEnd = strDirs.size() - 1;
 
         // up to first '**'
         while (patIdxStart <= patIdxEnd && strIdxStart <= strIdxEnd) {
             String patDir = (String)patDirs.get(patIdxStart);
             if (patDir.equals("**")) {
                 break;
             }
             if (!match(patDir, (String)strDirs.get(strIdxStart), isCaseSensitive)) {
                 return false;
             }
             patIdxStart++;
             strIdxStart++;
         }
         if (strIdxStart > strIdxEnd) {
             // String is exhausted
             for (int i = patIdxStart; i <= patIdxEnd; i++) {
                 if (!patDirs.get(i).equals("**")) {
                     return false;
                 }
             }
             return true;
         }
         else {
             if (patIdxStart > patIdxEnd) {
                 // String not exhausted, but pattern is. Failure.
                 return false;
             }
         }
 
         // up to last '**'
         while (patIdxStart <= patIdxEnd && strIdxStart <= strIdxEnd) {
             String patDir = (String)patDirs.get(patIdxEnd);
             if (patDir.equals("**")) {
                 break;
             }
             if (!match(patDir, (String)strDirs.get(strIdxEnd), isCaseSensitive)) {
                 return false;
             }
             patIdxEnd--;
             strIdxEnd--;
         }
         if (strIdxStart > strIdxEnd) {
             // String is exhausted
             for (int i = patIdxStart; i <= patIdxEnd; i++) {
                 if (!patDirs.get(i).equals("**")) {
                     return false;
                 }
             }
             return true;
         }
 
         while (patIdxStart != patIdxEnd && strIdxStart <= strIdxEnd) {
             int patIdxTmp = -1;
             for (int i = patIdxStart + 1; i <= patIdxEnd; i++) {
                 if (patDirs.get(i).equals("**")) {
                     patIdxTmp = i;
                     break;
                 }
             }
             if (patIdxTmp == patIdxStart + 1) {
                 // '**/***' situation, so skip one
                 patIdxStart++;
                 continue;
             }
 
             // Find the pattern between padIdxStart & padIdxTmp in str between
             // strIdxStart & strIdxEnd
             int patLength = (patIdxTmp - patIdxStart - 1);
             int strLength = (strIdxEnd - strIdxStart + 1);
             int foundIdx = -1;
 strLoop: 
             for (int i = 0; i <= strLength - patLength; i++) {
                 for (int j = 0; j < patLength; j++) {
                     String subPat = (String)patDirs.get(patIdxStart + j + 1);
                     String subStr = (String)strDirs.get(strIdxStart + i + j);
                     if (!match(subPat, subStr, isCaseSensitive)) {
                         continue strLoop;
                     }
                 }
 
                 foundIdx = strIdxStart + i;
                 break;
             }
 
             if (foundIdx == -1) {
                 return false;
             }
 
             patIdxStart = patIdxTmp;
             strIdxStart = foundIdx + patLength;
         }
 
         for (int i = patIdxStart; i <= patIdxEnd; i++) {
             if (!patDirs.get(i).equals("**")) {
                 return false;
             }
         }
 
         return true;
     }
 
 
     /**
      * Tests whether or not a string matches against a pattern.
      * The pattern may contain two special characters:<br>
      * '*' means zero or more characters<br>
      * '?' means one and only one character
      *
      * @param pattern The pattern to match against.
      *                Must not be <code>null</code>.
      * @param str     The string which must be matched against the pattern.
      *                Must not be <code>null</code>.
      * @param isCaseSensitive Whether or not matching should be performed
      *                        case sensitively.
      *
      *
      * @return <code>true</code> if the string matches against the pattern,
      *         or <code>false</code> otherwise.
      */
     public static boolean match(String pattern, String str, boolean isCaseSensitive) {
         char[] patArr = pattern.toCharArray();
         char[] strArr = str.toCharArray();
         int patIdxStart = 0;
         int patIdxEnd = patArr.length - 1;
         int strIdxStart = 0;
         int strIdxEnd = strArr.length - 1;
         char ch;
 
         boolean containsStar = false;
         for (int i = 0; i < patArr.length; i++) {
             if (patArr[i] == '*') {
                 containsStar = true;
                 break;
             }
         }
 
         if (!containsStar) {
             // No '*'s, so we make a shortcut
             if (patIdxEnd != strIdxEnd) {
                 return false; // Pattern and string do not have the same size
             }
             for (int i = 0; i <= patIdxEnd; i++) {
                 ch = patArr[i];
                 if (ch != '?') {
                     if (isCaseSensitive && ch != strArr[i]) {
                         return false; // Character mismatch
                     }
                     if (!isCaseSensitive
                             && Character.toUpperCase(ch) != Character.toUpperCase(
                                 strArr[i])) {
                         return false; // Character mismatch
                     }
                 }
             }
             return true; // String matches against pattern
         }
 
         if (patIdxEnd == 0) {
             return true; // Pattern contains only '*', which matches anything
         }
 
         // Process characters before first star
         while ((ch = patArr[patIdxStart]) != '*' && strIdxStart <= strIdxEnd) {
             if (ch != '?') {
                 if (isCaseSensitive && ch != strArr[strIdxStart]) {
                     return false; // Character mismatch
                 }
                 if (!isCaseSensitive
                         && Character.toUpperCase(ch) != Character.toUpperCase(
                             strArr[strIdxStart])) {
                     return false; // Character mismatch
                 }
             }
             patIdxStart++;
             strIdxStart++;
         }
         if (strIdxStart > strIdxEnd) {
             // All characters in the string are used. Check if only '*'s are
             // left in the pattern. If so, we succeeded. Otherwise failure.
             for (int i = patIdxStart; i <= patIdxEnd; i++) {
                 if (patArr[i] != '*') {
                     return false;
                 }
             }
             return true;
         }
 
         // Process characters after last star
         while ((ch = patArr[patIdxEnd]) != '*' && strIdxStart <= strIdxEnd) {
             if (ch != '?') {
                 if (isCaseSensitive && ch != strArr[strIdxEnd]) {
                     return false; // Character mismatch
                 }
                 if (!isCaseSensitive
                         && Character.toUpperCase(ch) != Character.toUpperCase(
                             strArr[strIdxEnd])) {
                     return false; // Character mismatch
                 }
             }
             patIdxEnd--;
             strIdxEnd--;
         }
         if (strIdxStart > strIdxEnd) {
             // All characters in the string are used. Check if only '*'s are
             // left in the pattern. If so, we succeeded. Otherwise failure.
             for (int i = patIdxStart; i <= patIdxEnd; i++) {
                 if (patArr[i] != '*') {
                     return false;
                 }
             }
             return true;
         }
 
         // process pattern between stars. padIdxStart and patIdxEnd point
         // always to a '*'.
         while (patIdxStart != patIdxEnd && strIdxStart <= strIdxEnd) {
             int patIdxTmp = -1;
             for (int i = patIdxStart + 1; i <= patIdxEnd; i++) {
                 if (patArr[i] == '*') {
                     patIdxTmp = i;
                     break;
                 }
             }
             if (patIdxTmp == patIdxStart + 1) {
                 // Two stars next to each other, skip the first one.
                 patIdxStart++;
                 continue;
             }
 
             // Find the pattern between padIdxStart & padIdxTmp in str between
             // strIdxStart & strIdxEnd
             int patLength = (patIdxTmp - patIdxStart - 1);
             int strLength = (strIdxEnd - strIdxStart + 1);
             int foundIdx = -1;
 strLoop: 
             for (int i = 0; i <= strLength - patLength; i++) {
                 for (int j = 0; j < patLength; j++) {
                     ch = patArr[patIdxStart + j + 1];
                     if (ch != '?') {
                         if (isCaseSensitive && ch != strArr[strIdxStart + i + j]) {
                             continue strLoop;
                         }
                         if (!isCaseSensitive
                                 && Character.toUpperCase(ch) != Character.toUpperCase(
                                     strArr[strIdxStart + i + j])) {
                             continue strLoop;
                         }
                     }
                 }
 
                 foundIdx = strIdxStart + i;
                 break;
             }
 
             if (foundIdx == -1) {
                 return false;
             }
 
             patIdxStart = patIdxTmp;
             strIdxStart = foundIdx + patLength;
         }
 
         // All characters in the string are used. Check if only '*'s are left
         // in the pattern. If so, we succeeded. Otherwise failure.
         for (int i = patIdxStart; i <= patIdxEnd; i++) {
             if (patArr[i] != '*') {
                 return false;
             }
         }
         return true;
     }
 
 
     /***
      * Breaks a path up into a Vector of path elements, tokenizing on
      * <code>File.separator</code>.
      *
      * @param path Path to tokenize. Must not be <code>null</code>.
      *
      * @return a Vector of path elements from the tokenized path
      */
     public static List tokenizePath(String path) {
         List ret = new ArrayList();
         StringTokenizer st = new StringTokenizer(path, File.separator);
         while (st.hasMoreTokens()) {
             ret.add(st.nextToken());
         }
         return ret;
     }
 }