package er.extensions.components._private;
import org.apache.log4j.Logger;

import com.webobjects.appserver.WOContext;
import com.webobjects.appserver.WOElement;
import com.webobjects.appserver.WORequest;
import com.webobjects.appserver.WOResponse;
import com.webobjects.appserver._private.WODynamicElementCreationException;
import com.webobjects.foundation.NSDictionary;

import er.extensions.appserver.ERXSession;
import er.extensions.appserver.ERXWOContext;

/**
 * Enhanced WOFileUpload.
 * <ul>
 *  <li> throws an IllegalArgumentException when it is embedded in a WOForm that does not have enctype=multipart/form-data
 *  <li> catches "ran out of data" IllegalStateException in superclass when the user backtracked.
 *</ul>
 * @created ak on Wed Oct 09 2002
 * @project ERExtensions
 */

public class ERXWOFileUpload extends com.webobjects.appserver._private.WOFileUpload {

    /** logging support */
    private static final Logger log = Logger.getLogger(ERXWOFileUpload.class);
	
    /**
     * Public constructor
     */
    public ERXWOFileUpload(String string, NSDictionary nsdictionary,
                        WOElement woelement) {
        super(string, nsdictionary, woelement);
        if (nsdictionary.objectForKey("data") != null && nsdictionary.objectForKey("filePath") == null) {
            throw new WODynamicElementCreationException("<" + getClass().getName() + "> 'filePath' must be bound if 'data' is bound.");
        }
    }

    public void checkEnctype(WOContext context) {
    	if(!("multipart/form-data".equals(ERXWOContext.contextDictionary().objectForKey("enctype")))) {
    		throw new IllegalArgumentException("This form is missing a 'enctype=multipart/form-data' attribute. It is required for WOFileUpload to work.");
    	}
    }
    
    @Override
	public void takeValuesFromRequest(WORequest worequest, WOContext wocontext) {
    	try {
    		super.takeValuesFromRequest(worequest, wocontext);
    	} catch(IllegalStateException ex) {
    		// AK: Safari has the habit of posting only a part of the request when you backtrack and
    		// this in turn triggers an IllegalStateException in our superclass
    		// so we only rethrow when we didn't backtrack
    		boolean doThrow = !wocontext.hasSession() || !(wocontext.session() instanceof ERXSession) || !((ERXSession)wocontext.session()).didBacktrack();
    		if(doThrow) {
    			throw ex;
    		} else {
    			log.info("Ignoring a problem when reading the form values as the user backtracked: " + ex);
    		}
    	}
        catch(RuntimeException ex) {
            // SE: same code as above.  With Safari and some other browsers,
            // backtracking may lead to a submission that contains no data
            // for the file upload control, but this may result in a
            // RuntimeException exception instead of IllegalStateException
            // ("Could not create output stream. 'outputStream', or
            // 'streamToFilePath' may have evaluated to null. No Upload
            // performed.")
            boolean doThrow = !wocontext.hasSession() || !(wocontext.session() instanceof ERXSession) || !((ERXSession)wocontext.session()).didBacktrack();
            if(doThrow) {
                throw ex;
            } else {
                log.info("Ignoring a problem when reading the form values as the user backtracked: " + ex);
            }
        }
    }
    
    @Override
	public void appendToResponse(WOResponse response, WOContext context) {
        checkEnctype(context);
        super.appendToResponse(response, context);
    }
}