package edu.upmc.ccweb.stripesCommon.stripes;

import java.util.Collection;
import java.util.Locale;

import sun.net.util.IPAddressUtil;

import net.sourceforge.stripes.validation.ScopedLocalizableError;
import net.sourceforge.stripes.validation.TypeConverter;
import net.sourceforge.stripes.validation.ValidationError;

/**
 * <p>A faux TypeConverter that validates that the String supplied is a valid IPv4 address.
 * Relies on sun.net.util.IPAddressUtil for the bulk of the work.</p>
 *
 * <p>If the String cannot be parsed, a single error message will be generated.  The error
 * message is a scoped message with a default scope of <tt>converter.ip</tt> and name
 * <tt>invalidIp</tt>.  As a result error messages will be looked for in the following
 * order:</p>
 *
 * <ul>
 *   <li>actionPath.fieldName.invalidIp</li>
 *   <li>actionPath.invalidIp</li>
 *   <li>converter.email.invalidIp</li>
 * </ul>
 *
 */
public class IpTypeConverter implements TypeConverter<String>  {

	/** Accepts the Locale provide, but does nothing with it since IPs are Locale-less. */
	public void setLocale(Locale locale) { /* Doesn't matter for IP. */}

	/**
	  * Validates the user input to ensure that it is a valid IP address.
	  *
	  * @param input the String input, always a non-null non-empty String
	  * @param targetType realistically always String since java.lang.String is final
	  * @param errors a non-null collection of errors to populate in case of error
	  * @return the parsed IP address, or null if there are errors.
	  */
	public String convert(String input,
							Class<? extends String> targetType,
							Collection<ValidationError> errors)  {
		if (IPAddressUtil.isIPv4LiteralAddress(input))  {
			return input;
		}
		errors.add(new ScopedLocalizableError("converter.ip", "invalidIp"));
		return null;
	}
}