//
// This software is now distributed according to
// the Lesser Gnu Public License.  Please see
// http://www.gnu.org/copyleft/lesser.txt for
// the details.
//    -- Happy Computing!
//
package com.stevesoft.pat;

import java.util.Hashtable;

/** This class matches a single character. */
class oneChar extends Pattern
{
  char c, altc, altc2;

  int mask;

  public oneChar(char ci)
  {
    c = ci;
    char cu, cl, ct;
    cu = CaseMgr.toUpperCase(c);
    cl = CaseMgr.toLowerCase(c);
    ct = CaseMgr.toTitleCase(c);
    if (c == cu)
    {
      altc = cl;
      altc2 = ct;
    }
    else if (c == cl)
    {
      altc = cu;
      altc2 = ct;
    }
    else
    {
      altc = cl;
      altc2 = cu;
    }
    mask = c & altc & altc2;
  }

  public int matchInternal(int pos, Pthings pt)
  {
    char p;
    int ret = -1;
    if (pos < pt.src.length() && !Masked(pos, pt)
            && ((p = pt.src.charAt(pos)) == c
                    || (pt.ignoreCase && (p == altc || p == altc2))))
    {
      ret = nextMatch(pos + 1, pt);
    }
    return ret;
  }

  public String toString()
  {
    return protect("" + c, PROTECT_THESE, ESC) + nextString();
  }

  public patInt minChars()
  {
    return new patInt(1);
  }

  public patInt maxChars()
  {
    return new patInt(1);
  }

  Pattern clone1(Hashtable h)
  {
    return new oneChar(c);
  }
};