package de.intevation.flys.client.client.utils;
import com.google.gwt.core.client.GWT;
import com.smartgwt.client.widgets.form.DynamicForm;
import com.smartgwt.client.widgets.form.fields.FormItem;
import com.google.gwt.i18n.client.NumberFormat;
import com.smartgwt.client.widgets.form.fields.events.ChangedHandler;
import com.smartgwt.client.widgets.form.fields.events.ChangedEvent;
import java.util.Map;
import de.intevation.flys.client.client.FLYSConstants;

/**
 * @author <a href="mailto:raimund.renkert@intevation.de">Raimund Renkert</a>
 *
 * This validator is used for SmartGWT FormItems.
 *
 * To use this validator an attribute named 'internalType' has to be set.
 * Values for 'internalType':
 *   'double'
 *   'integer'
 */
public class Validator implements ChangedHandler {

    /** The interface that provides i18n messages. */
    protected FLYSConstants MSG = GWT.create(FLYSConstants.class);


    /**
     *
     */
    public void onChanged(ChangedEvent e) {
        FormItem item = e.getItem();
        DynamicForm form = e.getForm();
        Map errors = form.getErrors();
        String type = item.getAttribute("internalType");

        if(type.equals("double")) {
            validateFloat(item, errors);
            form.setErrors(errors, true);
        }
        else if(type.equals("integer")) {
            validateInteger(item, errors);
            form.setErrors(errors, true);
        }
        else {
            GWT.log("No Attribute 'internalType' set. Not using any validator.");
        }
    }


    /**
     *
     */
    protected boolean validateInteger(FormItem item, Map errors) {
        boolean valid = true;

        String v = (String) item.getValue();

        NumberFormat f = NumberFormat.getDecimalFormat();

        try {
            if (v == null) {
                throw new NumberFormatException("empty");
            }

            int value = Integer.parseInt(v);

            errors.remove(item.getFieldName());
        }
        catch (NumberFormatException nfe) {
            errors.put(item.getFieldName(), MSG.wrongFormat());

            item.focusInItem();

            valid = false;
        }
        return valid;
    }


    /**
     *
     */
    protected boolean validateFloat(FormItem item, Map errors) {
        boolean valid = true;

        String v = (String) item.getValue();

        NumberFormat f = NumberFormat.getDecimalFormat();

        try {
            if (v == null) {
                throw new NumberFormatException("empty");
            }

            double value = f.parse(v);

            errors.remove(item.getFieldName());
        }
        catch (NumberFormatException nfe) {
            errors.put(item.getFieldName(), MSG.wrongFormat());

            item.focusInItem();

            valid = false;
        }
        return valid;
    }
}