// ToolsListerFrame.java
// $Id: ToolsListerFrame.java,v 1.8 1999/04/14 14:43:23 bmahe Exp $
// (c) COPYRIGHT MIT and INRIA, 1998.
// Please first read the full copyright statement in file COPYRIGHT.html

package org.w3c.jigedit.tools ;

import java.io.* ;
import java.util.* ;

import org.w3c.tools.resources.*;
import org.w3c.tools.sorter.*;
import org.w3c.www.mime.*;
import org.w3c.jigsaw.forms.*;
import org.w3c.jigsaw.http.* ;
import org.w3c.jigsaw.html.* ;
import org.w3c.jigsaw.frames.* ;
import org.w3c.jigedit.cvs.CvsFrame;
import org.w3c.www.http.* ;
import org.w3c.tools.resources.event.*;

/**
 * Emit the content of its parent directory.
 */
public class ToolsListerFrame extends PostableFrame 
                              implements StructureChangedListener 
{
    private static final boolean debug = false;
    
    private boolean invalid = true;

    private ResourceReference dirResourceRef = null;

    protected ResourceReference getDirResourceRef() {
	if (invalid || (dirResourceRef == null)) {
	    dirResourceRef = getResource().getParent();
	}
	return dirResourceRef;
    }

    public void registerResource(FramedResource resource) {
	super.registerOtherResource(resource);
	dirResourceRef = resource.getParent();
	try {
	    FramedResource fres = (FramedResource)dirResourceRef.lock();
	    // register us as a listener 
	    fres.addStructureChangedListener(this);
	} catch(InvalidResourceException ex) {
	    ex.printStackTrace();
	} finally {
	    dirResourceRef.unlock();
	}
	invalid = false;
    }

    /**
     * Unused here.
     */
    public void resourceModified(StructureChangedEvent evt) { }

    /**
     * Unused here.
     */
    public void resourceCreated(StructureChangedEvent evt) { }
    
    public void resourceUnloaded(StructureChangedEvent evt){ }

    /**
     * A resource is about to be removed
     * This handles the <code>RESOURCE_REMOVED</code> kind of events.
     * @param evt The event describing the change.
     */

    public void resourceRemoved(StructureChangedEvent evt) {
	invalid = true;
    }
    
    protected Class httpClass = null;

    protected String getResourceLine(ResourceReference rr, String name) {
	if (httpClass == null) {
	    try {
		httpClass=Class.forName("org.w3c.jigsaw.frames.HTTPFrame");
	    } catch (ClassNotFoundException ex) {
		httpClass = null;
	    }
	}
	StringBuffer buffer = new StringBuffer(100);
	try {
	    FramedResource resource = (FramedResource) rr.lock();
	    if (name == null)
		name = resource.getIdentifier();
	    buffer.append("<tr align=\"left\" valign=\"bottom\">");
	    HTTPFrame itsframe = null;
	    if (httpClass != null)
		itsframe = (HTTPFrame)resource.getFrame(httpClass);
	    if (itsframe instanceof CvsFrame) {
		buffer.append("<td></td>");
	    } else {
		buffer.append("<td>");
		buffer.append("<INPUT TYPE=\"CHECKBOX\" NAME=\"" + name
			      + "\"> ");
		buffer.append("</td>");
	    }
	    buffer.append("<td>");
	    if (itsframe != null) {
		String icon = itsframe.getIcon() ;
		if ( icon != null ) 
		    buffer.append("<IMG SRC=\""+
				  getIconDirectory() +"/" + icon+
				  "\">");
		// Resource's name with link:
		buffer.append("<A HREF=\""+resource.getURLPath()+
			      "\">"+name+"</A>");
		// resource's title, if any:
		String title = itsframe.getTitle();
		if (title != null)
		    buffer.append(" "+title);
	    } else {
		// Resource's name with link:
		buffer.append("<A HREF=\""+resource.getURLPath()+
			      "\">"+name+"</A>"+" Not available via HTTP");
		buffer.append("<BR>\n");
	    }
	    buffer.append("</td></tr>\n");
	} catch (InvalidResourceException ex) {
	    buffer.append("<td> "+name);
	    buffer.append("cannot be loaded (server misconfigured)");
	    buffer.append("<BR>");
	    buffer.append("</td></tr>\n");
	} finally {
	    rr.unlock();
	}
	return buffer.toString();
    }

    /**
     * Get the directory listing.
     * @param request the incomming request.
     * @exception ProtocolException if a protocol error occurs
     * @exception ResourceException if a server error occurs
     */
    public synchronized Reply getDirectoryListing(Request request)
	throws ProtocolException, ResourceException
    {
	DirectoryResource dirResource = null;
	try {
	    dirResource = (DirectoryResource) getDirResourceRef().lock();
	    if (dirResource == null) 
		throw new ResourceException("parent is NOT a "+
					    "DirectoryResource. ("+
					    resource.getIdentifier()+")");
	    if (! dirResource.verify()) {
		// the directory was deleted, but we can't delete it here
		// (Multiple Locks)
		// Emit an error back:
		Reply error = request.makeReply(HTTP.NOT_FOUND) ;
		error.setContent ("<h1>Document not found</h1>"+
				  "<p>The document "+
				  request.getURL()+
				  " is indexed but not available."+
				  "<p>The server is misconfigured.") ;
		throw new HTTPException (error) ;
	    }
	    // Have we already an up-to-date computed a listing ?
	    if ((listing == null) 
		|| (dirResource.getDirectory().lastModified() > listing_stamp)
		|| (dirResource.getLastModified() > listing_stamp)
		|| (getLastModified() > listing_stamp)) {
		
		Enumeration enum = dirResource.enumerateResourceIdentifiers() ;
		Vector        resources = Sorter.sortStringEnumeration(enum) ;
		HtmlGenerator g = new HtmlGenerator("Directory listing of "+
						  dirResource.getIdentifier());
		// Add style link
		addStyleSheet(g);
		g.append("<H1>Directory listing of ",
			 dirResource.getIdentifier(),
			 "</H1>");
		// Link to the parent, when possible:
		if ( dirResource.getParent() != null )
		    g.append("<P><A HREF=\"..\">Parent</A><BR>");
		g.append("\n<FORM METHOD=\"POST\">\n");
		String listername = getResource().getIdentifier();
		// List the children:
		g.append("<table border=\"0\">\n");

		ResourceReference rr       = null;
		FramedResource    resource = null;
		String            name     = null;
		//ugly hack to put CVS link first
		rr = dirResource.lookup("CVS");
		if (rr != null)
		    g.append(getResourceLine(rr, "CVS"));

		for (int i = 0 ; i < resources.size() ; i++) {
		    name = (String) resources.elementAt(i);
		    if ( name.equals(listername) || name.equals("CVS"))
			continue;
		    rr = dirResource.lookup(name);
		    g.append(getResourceLine(rr, name));
		}
		g.append("</table>\n");
		g.append("<P><INPUT TYPE=\"SUBMIT\" NAME=\"SUBMIT\" VALUE=\""+
			 "Delete file from  publishing space\"></FORM>\n");
		g.close() ;
		listing_stamp = getLastModified() ;
		listing       = g ;
	    } else if ( checkIfModifiedSince(request) == COND_FAILED ) {
		// Is it an IMS request ?
		return createDefaultReply(request, HTTP.NOT_MODIFIED) ;
	    }
	} catch (InvalidResourceException ex) {
	    return createDefaultReply(request, HTTP.INTERNAL_SERVER_ERROR);
	} finally {
	    getDirResourceRef().unlock();
	}
	// New content or need update:
	Reply reply = createDefaultReply(request, HTTP.OK) ;
	reply.setLastModified(listing_stamp) ;
	reply.setStream(listing) ;
	return reply ;
    }

    /**
     * @exception org.w3c.tools.resources.ProtocolException 
     * if a protocol error occurs
     * @exception org.w3c.tools.resources.ResourceException 
     * if a server error occurs
     */
    protected Reply getOtherResource (Request request) 
	throws ProtocolException, ResourceException  
    {
	return getDirectoryListing(request);
    }

    /**
     * Handle the form submission, after posted data parsing.
     * <p>This method ought to be abstract, but for reasonable reason, it
     * will just dump (parsed) the form content back to the client, so that it
     * can be used for debugging.
     * @param request The request proper.
     * @param data The parsed data content.
     * @exception ProtocolException If form data processing failed.
     * @see org.w3c.jigsaw.forms.URLDecoder
     */
    
    public Reply handle (Request request, URLDecoder data)
	throws ProtocolException
    {
	Reply r;
	Enumeration   e = data.keys() ;
	while ( e.hasMoreElements () ) {
	    String name = (String) e.nextElement() ;
	    if (name.equals("SUBMIT"))
		continue;
	    // delete file now... avoit deleting CVS and lister
	    // (should be in an attribute)
	    synchronized (this) {
		DirectoryResource dr;
		Resource toDeleteRes;
		ResourceReference rr;
		File dir, toDeleteFile;
		try {
		    dr = (DirectoryResource) getDirResourceRef().lock();
		    dir = dr.getDirectory();
		    if (debug)
			System.out.println("Deleting " + name);
		    rr = dr.lookup(name);
		    if (rr != null) {
			try {
			    toDeleteFile = new File(dir, name);
			    toDeleteFile.delete();
			} catch (Exception ex) {
			    // fancy message. file not present
			    // Or security manager forbiding deletion.
			}
			// and now, at least remove the resource
			try {
			    toDeleteRes = (Resource) rr.lock();
			    toDeleteRes.delete();
			} catch (Exception ex) {
			    // some other locks... or pb with the resource
			} finally {
			    rr.unlock();
			}
		    }
		} catch (Exception ex) {
		    // some other locks... abort
		} finally {
		    getDirResourceRef().unlock();
		}
	    }
	}
	try {
	    r = getDirectoryListing(request);
	} catch (ResourceException ex) {
	    r = createDefaultReply(request, HTTP.INTERNAL_SERVER_ERROR);
	}
	return r;
    }
}
