This is my first cut at a feature like that requested in [[todo/Moving_Pages]]. In case it gets mangled you can find it on [my site](http://www.betacantrips.com//attic/move.patch).

A bunch of obvious shortcomings exist: 

* I'm not sure all the untaints are safe.
* No precautions whatsoever are made to protect against race conditions or failures
  in the rcs\_move function.
* movepage.tmpl doesn't exist yet.
* Some code is duplicated between cgi\_movepage and cgi\_editpage, as well
  as rcs\_commit and rcs\_move.
* The user interface is pretty lame -- there's no handy select list full 
  of possible places to move it or anything.
* I don't think I implemented cancelling.
* from is redundant with page.
* I don't think I called the right hook functions.
* No redirect pages like those mentioned on [[todo/Moving_Pages]] exist yet, 
  so none are created.
* It's not possible to get there through the actions listed on the wiki page.
  Instead you can select "Edit" and then change "edit" to "move" in the 
  location bar.

Anyhow, here's the patch, for whatever good it does.

> Looks like a good start, although I agree about many of the points above,
> and also feel that something needs to be done about rcses that don't
> implement a move operation -- falling back to an add and delete.
> --[[Joey]]

Hmm. Shouldn't that be done on a by-RCS basis, though? (i.e. implemented
by backends in the `rcs_move` function)

Also, how should ikiwiki react if a page is edited (say, by another user)
before it is moved? Bail, or shrug and proceed?

Could you elaborate on [[commit-internals]]? Can I assume that ikiwiki's 
working copy W will always reflect a revision of the master copy M? 
(That is, nobody changes W and leaves it uncommitted.) I would guess 
probably not; a user probably expects that if he starts editing W it 
won't get randomly committed by web user actions. But then looking at
the svn backend, it looks like if I edit foo.mdwn, don't commit, and then
a web user makes different changes, my changes get wiped out. So does
W "belong" to ikiwiki? --Ethan


    diff -urx .svn ikiwiki/IkiWiki/CGI.pm ikiwiki-new/IkiWiki/CGI.pm
    --- ikiwiki/IkiWiki/CGI.pm	2007-01-04 03:52:47.000000000 -0800
    +++ ikiwiki-new/IkiWiki/CGI.pm	2007-01-11 18:49:37.000000000 -0800
    @@ -523,6 +523,97 @@
     	}
     } #}}}
     
    +sub cgi_movepage($$) {
    +	my $q = shift;
    +	my $session = shift;
    +	eval q{use CGI::FormBuilder};
    +	error($@) if $@;
    +	my @fields=qw(do from rcsinfo subpage page newname message); # subpage ignored so far
    +	my @buttons=("Rename Page", "Cancel");
    +
    +	my $form = CGI::FormBuilder->new(
    +		fields => \@fields,
    +                header => 1,
    +                charset => "utf-8",
    +                method => 'POST',
    +		action => $config{cgiurl},
    +                template => (-e "$config{templatedir}/movepage.tmpl" ?
    +			     {template_params("movepage.tpml")} : ""),
    +	);
    +	run_hooks(formbuilder_setup => sub {
    +		shift->(form => $form, cgi => $q, session => $session);
    +	});
    +
    +	decode_form_utf8($form);
    +	
    +	# This untaint is safe because if the page doesn't exist, bail.
    +	my $page = $form->field('page');
    +	$page = possibly_foolish_untaint($page);
    +	if (! exists $pagesources{$page}) {
    +		error("page does not exist");
    +	}
    +	my $file=$pagesources{$page};
    +	my $type=pagetype($file);
    +
    +	my $from;
    +	if (defined $form->field('from')) {
    +		($from)=$form->field('from')=~/$config{wiki_file_regexp}/;
    +	}
    +	
    +	$form->field(name => "do", type => 'hidden');
    +	$form->field(name => "from", type => 'hidden');
    +	$form->field(name => "rcsinfo", type => 'hidden');
    +	$form->field(name => "subpage", type => 'hidden');
    +	$form->field(name => "page", value => $page, force => 1);
    +	$form->field(name => "newname", type => "text", size => 80);
    +	$form->field(name => "message", type => "text", size => 80);
    +
    +	if (! $form->submitted) {
    +		$form->field(name => "rcsinfo", value => rcs_prepedit($file),
    +			     force => 1);
    +	}
    +
    +	if ($form->submitted eq "Cancel") {
    +		redirect($q, "$config{url}/".htmlpage($from));
    +		return;
    +	}
    +		
    +	if (! $form->submitted || $form->submitted eq "Preview" || 
    +	    ! $form->validate) {
    +		if ($form->field("do") eq "move"){
    +			page_locked($page, $session);
    +			$form->tmpl_param("page_select", 0);
    +			$form->field(name => "page", type => 'hidden');
    +			$form->field(name => "type", type => 'hidden');
    +			$form->title(sprintf(gettext("moving %s"), pagetitle($page)));
    +			if (! defined $form->field('newname') ||
    +			    ! length $form->field('newname')) {
    +				$form->field(name => "newname", 
    +					     value => pagetitle($page), force => 1);
    +			}
    +
    +		}
    +		print $form->render(submit => \@buttons);
    +	}
    +	else{
    +		# This untaint is safe because titlepage removes any problematic
    +		# characters.
    +		my ($newname)=$form->field('newname');
    +		$newname=titlepage(possibly_foolish_untaint($newname));
    +		if (! defined $newname || ! length $newname || file_pruned($newname, $config{srcdir}) || $newname=~/^\//) {
    +			error("bad page name");
    +		}
    +		page_locked($page, $session);
    +
    +		my $newfile = $newname . ".$type";
    +		my $message = $form->field('message');
    +		unlockwiki();
    +		rcs_move($file, $newfile, $message, $form->field("rcsinfo"), 
    +			 $session->param("name"), $ENV{REMOTE_ADDR});
    +		redirect($q, "$config{url}/".htmlpage($newname));
    +	}
    +}
    +
     sub cgi_getsession ($) { #{{{
     	my $q=shift;
     
    @@ -631,6 +722,9 @@
     	if ($do eq 'create' || $do eq 'edit') {
     		cgi_editpage($q, $session);
     	}
    +	elsif ($do eq 'move') {
    +		cgi_movepage($q, $session);
    +	}
     	elsif ($do eq 'prefs') {
     		cgi_prefs($q, $session);
     	}
    diff -urx .svn ikiwiki/IkiWiki/Rcs/svn.pm ikiwiki-new/IkiWiki/Rcs/svn.pm
    --- ikiwiki/IkiWiki/Rcs/svn.pm	2006-12-28 17:50:46.000000000 -0800
    +++ ikiwiki-new/IkiWiki/Rcs/svn.pm	2007-01-11 18:14:30.000000000 -0800
    @@ -60,6 +60,34 @@
     	}
     } #}}}
     
    +sub rcs_move ($$$$;$$) {
    +	my $file=shift;
    +	my $newname=shift;
    +	my $message=shift;
    +	my $rcstoken=shift;
    +	my $user=shift;
    +	my $ipaddr=shift;
    +	if (defined $user) {
    +		$message="web commit by $user".(length $message ? ": $message" : "");
    +	}
    +	elsif (defined $ipaddr) {
    +		$message="web commit from $ipaddr".(length $message ? ": $message" : "");
    +	}
    +
    +	chdir($config{srcdir}); # svn merge wants to be here
    +
    +	if (system("svn", "move", "--quiet", 
    +		   "$file", "$newname") != 0) {
    +		return 1;
    +	}
    +	if (system("svn", "commit", "--quiet", 
    +		   "--encoding", "UTF-8", "-m",
    +		   possibly_foolish_untaint($message)) != 0) {
    +		return 1;
    +	}
    +	return undef # success
    +}
    +
     sub rcs_commit ($$$;$$) { #{{{
     	# Tries to commit the page; returns undef on _success_ and
     	# a version of the page with the rcs's conflict markers on failure.