package com.jclark.xsl.util;

class SwapCaseComparator implements Comparator {
  private Comparator cmp;

  SwapCaseComparator(Comparator cmp) {
    this.cmp = cmp;
  }

  public int compare(Object o1, Object o2) {
    return cmp.compare(swapCase((String)o1), swapCase((String)o2));
  }

  private String swapCase(String str) {
    char buf[] = new char[str.length()];
    str.getChars(0, buf.length, buf, 0);
    for (int i = 0; i < buf.length; i++)
      buf[i] = swapCase(buf[i]);
    return new String(buf);
  }

  char swapCase(char c) {
    char uc = Character.toUpperCase(c);
    if (c != uc)
      return uc;
    return Character.toLowerCase(c);
  }
}