package at.gv.egiz.pdfas.lib.impl.stamping;

import at.gv.egiz.pdfas.common.settings.IProfileConstants;
import at.gv.egiz.pdfas.common.settings.SignatureProfileSettings;
import at.gv.egiz.pdfas.lib.impl.PdfAsImpl;

import java.text.SimpleDateFormat;
import java.util.Calendar;
import java.util.Date;

import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

/**
 * Created with IntelliJ IDEA. User: afitzek Date: 9/11/13 Time: 11:11 AM To
 * change this template use File | Settings | File Templates.
 */
public class ValueResolver implements IProfileConstants {

	private static final Logger logger = LoggerFactory
			.getLogger(ValueResolver.class);

	private static final String defaultDateFormat = "yyyy-MM-dd'T'HH:mm:ss.SSS'Z'";

	public static final String EXP_START = "${";
	public static final String EXP_END = "}";

	// TODO: Currently just for proof of concept ...
	// Should support Reading Fields from Certificate and DATETIME

	// TODO: Use status in real implementation to get currently needed
	// informations...
	public String resolve(String key, String value,
			SignatureProfileSettings settings) {

		logger.debug("Resolving value for key: " + key);
		logger.debug("Resolving value with value: " + value);

		if (value != null) {
			if (value.startsWith(EXP_START) && value.endsWith(EXP_END)) {
				// TODO: handle OGNL expression for key and value
				// TODO: Here we need the certificate
				CertificateResolver certificateResolver = new CertificateResolver(
						null);
				String exp = value.substring(EXP_START.length(), value.length()
						- EXP_END.length());
				return certificateResolver.resolve(key, exp, settings);
			}
		}

		if (key.equals(SIG_DATE)) {
			if(value == null) {
				value = defaultDateFormat;
			}
			// Value holds the date format!
			SimpleDateFormat formater = new SimpleDateFormat(value);
			Calendar cal = Calendar.getInstance();
			return formater.format(cal.getTime());
		}

		return value;
	}

}