--- AttachFile.py	2005-01-16 14:35:08.642080009 +1300
+++ AttachFile_backup_with_dia.py	2005-01-16 14:36:17.776347814 +1300
@@ -23,7 +23,7 @@
     @license: GNU GPL, see COPYING for details.
 """
 
-import os, mimetypes, time, urllib
+import cgi, os, mimetypes, string, socket, sys, time, urllib, re
 from MoinMoin import config, user, util, wikiutil
 from MoinMoin.Page import Page
 from MoinMoin.util import MoinMoinNoFooter, filesys
@@ -141,6 +141,25 @@
     log.add(request, pagename, request.remote_addr, time.time(),
         urllib.quote(filename), action)
 
+def _backup_file(fpath):
+    """Move the file `fpath` to `fpath,nnn` where `nnn` is one plus `mmm`, where
+       `mmm` is the highest number for which `fpath.mmm` exists, or 000 if no
+       such file exists."""
+    
+    # find the right sequence number
+    dirname, basename = os.path.split(fpath)
+    backup_re = re.compile(r'^%s\,(?P<seq>\d\d\d)$' % basename)
+    backups = filter(backup_re.match, os.listdir(dirname))
+    backups.sort()
+    if backups == []:
+        seq_no = 0
+    else:
+        highest = backups[-1]
+        seq_no = int(backup_re.match(highest).group('seq')) + 1
+        
+    # do the move
+    new_name = "%s,%03d" % (fpath, seq_no)
+    os.rename(fpath, new_name)
 
 def _access_file(pagename, request):
     """ Check form parameter `target` and return a tuple of
@@ -175,6 +194,10 @@
         files = os.listdir(attach_dir)
         files.sort()
 
+    # filter out backup files
+    backup_re = re.compile(r'.*\,\d\d\d$')
+    files = filter(lambda x: not backup_re.match(x), files)
+
     str = ""
     if files:
         if showheader:
@@ -317,9 +340,9 @@
         return
 
     request.write('<h2>' + _("New Attachment") + '</h2><p>' +
-_("""An upload will never overwrite an existing file. If there is a name
-conflict, you have to rename the file that you want to upload.
-Otherwise, if "Rename to" is left blank, the original filename will be used.""") + '</p>')
+_("""When uploading under a filename for which an attachment already exists,
+the old version is stored - ask the administrator to recover it.</p>
+<p>If "Rename to" is left blank, the original filename will be used.""") + '</p>')
     request.write("""
 <form action="%(baseurl)s/%(pagename)s" method="POST" enctype="multipart/form-data">
 <dl>
@@ -448,25 +471,42 @@
         target = target + ext
     
     # get directory, and possibly create it
-    attach_dir = getAttachDir(pagename, create=1)
+    attach_dir = getAttachDir(pagename, create=1)        
+    
     # save file
     fpath = os.path.join(attach_dir, target)
     if os.path.exists(fpath):
-        msg = _("Attachment '%(target)s' (remote name '%(filename)s') already exists.") % {
-            'target': target, 'filename': filename}
-    else:
-        stream = open(fpath, 'wb')
-        try:
-            stream.write(filecontent)
-        finally:
-            stream.close()
-        os.chmod(fpath, 0666 & config.umask)
+        _backup_file(fpath)
 
-        bytes = len(filecontent)
-        msg = _("Attachment '%(target)s' (remote name '%(filename)s')"
-                " with %(bytes)d bytes saved.") % {
-                'target': target, 'filename': filename, 'bytes': bytes}
-        _addLogEntry(request, 'ATTNEW', pagename, target)
+    stream = open(fpath, 'wb')
+    try:
+        stream.write(filecontent)
+    finally:
+        stream.close()
+    os.chmod(fpath, 0666 & config.umask)
+    
+    extra = ''
+    if fpath.endswith('.dia'):
+        outputfile = os.path.join(os.getcwd(), fpath.replace('.dia','.svg'))
+	inputfile = os.path.join(os.getcwd(), fpath)
+
+	pipes = os.popen3('/bin/sh')
+	pipes[0].write('''dia -e %(output)s -t svg -n %(input)s
+exit
+''' % {'output' : outputfile, 'input' : inputfile})
+        pipes[0].flush()
+        res = pipes[1].readlines()
+        res = res + pipes[2].readlines()
+        pipes[0].close()
+        pipes[1].close()
+        pipes[2].close()
+        extra = 'processed %s to %s' % (inputfile, outputfile)
+        
+    bytes = len(filecontent)
+    msg = _("Attachment '%(target)s' (remote name '%(filename)s')"
+        " with %(bytes)d bytes saved. %(extra)s") % {
+        'target': target, 'filename': filename, 'bytes': bytes, 'extra' : extra}
+    _addLogEntry(request, 'ATTNEW', pagename, target)
 
     # return attachment list
     upload_form(pagename, request, msg)
@@ -511,7 +551,9 @@
     if not filename: return # error msg already sent in _access_file
     
     # delete file
-    os.remove(fpath)
+    if os.path.exists(fpath):
+        _backup_file(fpath)
+
     _addLogEntry(request, 'ATTDEL', pagename, filename)
 
     upload_form(pagename, request, msg=_("Attachment '%(filename)s' deleted.") % {'filename': filename})