package railo.runtime.db;
import java.util.Map;
import java.util.WeakHashMap;
import org.apache.oro.text.regex.MalformedPatternException;
import org.apache.oro.text.regex.Pattern;
import org.apache.oro.text.regex.Perl5Compiler;
import org.apache.oro.text.regex.Perl5Matcher;
import railo.commons.lang.StringUtil;
import railo.runtime.exp.DatabaseException;
import railo.runtime.exp.PageException;
import railo.runtime.op.Caster;
/**
* Wildcard Filter
*/
class LikeComparePerl {
private static final String specials="{}[]().+\\^$";
private static Perl5Matcher matcher=new Perl5Matcher();
private static Map patterns=new WeakHashMap();
static {
matcher.setMultiline(true);
}
private static Pattern createPattern(SQL sql, String wildcard, String escape) throws PageException {
Pattern pattern=(Pattern) patterns.get(wildcard+escape);
if(pattern!=null) return pattern;
char esc=0;
if(!StringUtil.isEmpty(escape)){
esc=escape.charAt(0);
if(escape.length()>1)throw new DatabaseException("Invalid escape character ["+escape+"] has been specified in a LIKE conditional",null,sql,null);
}
StringBuffer sb = new StringBuffer(wildcard.length());
int len=wildcard.length();
//boolean isEscape=false;
char c;
for(int i=0;i<len;i++) {
c = wildcard.charAt(i);
if(c == esc){
if(i+1==len)throw new DatabaseException("Invalid Escape Sequence. Valid sequence pairs for this escape character are: ["+esc+"%] or ["+esc+"_]",null,sql,null);
c = wildcard.charAt(++i);
if(c == '%')sb.append(c);
else if(c == '_') sb.append(c);
else throw new DatabaseException("Invalid Escape Sequence ["+esc+""+c+"]. Valid sequence pairs for this escape character are: ["+esc+"%] or ["+esc+"_]",null,sql,null);
}
else {
if(c == '%')sb.append(".*");
else if(c == '_') sb.append('.');
else if(specials.indexOf(c)!=-1)sb.append('\\').append(c);
else sb.append(c);
}
}
try {
patterns.put(wildcard+escape,pattern=new Perl5Compiler().compile(sb.toString(),Perl5Compiler.MULTILINE_MASK));
}
catch (MalformedPatternException e) {
throw Caster.toPageException(e);
}
return pattern;
}
public static boolean like(SQL sql, String haystack, String needle) throws PageException {
return like(sql, haystack, needle, null);
}
public static boolean like(SQL sql, String haystack, String needle,String escape) throws PageException {
return matcher.matches(StringUtil.toLowerCase(haystack), createPattern(sql,StringUtil.toLowerCase(needle),escape==null?null:StringUtil.toLowerCase(escape)));
}
}