#!/usr/bin/perl
package IkiWiki::Plugin::rename;

use warnings;
use strict;
use IkiWiki 2.00;

sub import { #{{{
	hook(type => "getsetup", id => "rename", call => \&getsetup);
	hook(type => "formbuilder_setup", id => "rename", call => \&formbuilder_setup);
	hook(type => "formbuilder", id => "rename", call => \&formbuilder);
	hook(type => "sessioncgi", id => "rename", call => \&sessioncgi);

} # }}}

sub getsetup () { #{{{
	return 
		plugin => {
			safe => 1,
			rebuild => 0,
		},
} #}}}

sub check_canrename ($$$$$$$) { #{{{
	my $src=shift;
	my $srcfile=shift;
	my $dest=shift;
	my $destfile=shift;
	my $q=shift;
	my $session=shift;
	my $attachment=shift;

	# Must be a known source file.
	if (! exists $pagesources{$src}) {
		error(sprintf(gettext("%s does not exist"),
			htmllink("", "", $src, noimageinline => 1)));
	}
	
	# Must exist on disk, and be a regular file.
	if (! -e "$config{srcdir}/$srcfile") {
		error(sprintf(gettext("%s is not in the srcdir, so it cannot be renamed"), $srcfile));
	}
	elsif (-l "$config{srcdir}/$srcfile" && ! -f _) {
		error(sprintf(gettext("%s is not a file"), $srcfile));
	}

	# Must be editable.
	IkiWiki::check_canedit($src, $q, $session);
	if ($attachment) {
		IkiWiki::Plugin::attachment::check_canattach($session, $src, $srcfile);
	}
	
	# Dest checks can be omitted by passing undef.
	if (defined $dest) {
		if ($srcfile eq $destfile) {
			error(gettext("no change to the file name was specified"));
		}

		# Must be a legal filename, and not absolute.
		if (IkiWiki::file_pruned($destfile, $config{srcdir}) || 
		    $destfile=~/^\//) {
			error(sprintf(gettext("illegal name")));
		}

		# Must not be a known source file.
		if ($src ne $dest && exists $pagesources{$dest}) {
			error(sprintf(gettext("%s already exists"),
				htmllink("", "", $dest, noimageinline => 1)));
		}
	
		# Must not exist on disk already.
		if (-l "$config{srcdir}/$destfile" || -e _) {
			error(sprintf(gettext("%s already exists on disk"), $destfile));
		}
	
		# Must be editable.
		IkiWiki::check_canedit($dest, $q, $session);
		if ($attachment) {
			# Note that $srcfile is used here, not $destfile,
			# because it wants the current file, to check it.
			IkiWiki::Plugin::attachment::check_canattach($session, $dest, $srcfile);
		}
	}
} #}}}

sub rename_form ($$$) { #{{{ 
	my $q=shift;
	my $session=shift;
	my $page=shift;

	eval q{use CGI::FormBuilder};
	error($@) if $@;
	my $f = CGI::FormBuilder->new(
		name => "rename",
		title => sprintf(gettext("rename %s"), IkiWiki::pagetitle($page)),
		header => 0,
		charset => "utf-8",
		method => 'POST',
		javascript => 0,
		params => $q,
		action => $config{cgiurl},
		stylesheet => IkiWiki::baseurl()."style.css",
		fields => [qw{do page new_name attachment}],
	);
	
	$f->field(name => "do", type => "hidden", value => "rename", force => 1);
	$f->field(name => "page", type => "hidden", value => $page, force => 1);
	$f->field(name => "new_name", value => IkiWiki::pagetitle($page), size => 60);
	if (!$q->param("attachment")) {
		# insert the standard extensions
		my @page_types;
		if (exists $IkiWiki::hooks{htmlize}) {
			@page_types=grep { !/^_/ }
				keys %{$IkiWiki::hooks{htmlize}};
		}
	
		# make sure the current extension is in the list
		my ($ext) = $pagesources{$page}=~/\.([^.]+)$/;
		if (! $IkiWiki::hooks{htmlize}{$ext}) {
			unshift(@page_types, $ext);
		}
	
		$f->field(name => "type", type => 'select',
			options => \@page_types,
			value => $ext, force => 1);
	}
	$f->field(name => "attachment", type => "hidden");

	return $f, ["Rename", "Cancel"];
} #}}}

sub rename_start ($$$$) { #{{{
	my $q=shift;
	my $session=shift;
	my $attachment=shift;
	my $page=shift;

	check_canrename($page, $pagesources{$page}, undef, undef,
		$q, $session, $attachment);

   	# Save current form state to allow returning to it later
	# without losing any edits.
	# (But don't save what button was submitted, to avoid
	# looping back to here.)
	# Note: "_submit" is CGI::FormBuilder internals.
	$q->param(-name => "_submit", -value => "");
	$session->param(postrename => scalar $q->Vars);
	IkiWiki::cgi_savesession($session);
	
	my ($f, $buttons)=rename_form($q, $session, $page);
	if (defined $attachment) {
		$f->field(name => "attachment", value => $attachment, force => 1);
	}
	
	IkiWiki::showform($f, $buttons, $session, $q);
	exit 0;
} #}}}

sub postrename ($;$$$) { #{{{
	my $session=shift;
	my $src=shift;
	my $dest=shift;
	my $attachment=shift;

	# Load saved form state and return to edit page.
	my $postrename=CGI->new($session->param("postrename"));
	$session->clear("postrename");
	IkiWiki::cgi_savesession($session);

	if (defined $dest) {
		if (! $attachment) {
			# They renamed the page they were editing. This requires
			# fixups to the edit form state.
			# Tweak the edit form to be editing the new page.
			$postrename->param("page", $dest);
		}

		# Update edit form content to fix any links present
		# on it.
		$postrename->param("editcontent",
			renamepage_hook($dest, $src, $dest,
				 $postrename->param("editcontent")));

		# Get a new edit token; old was likely invalidated.
		$postrename->param("rcsinfo",
			IkiWiki::rcs_prepedit($pagesources{$dest}));
	}

	IkiWiki::cgi_editpage($postrename, $session);
} #}}}

sub formbuilder (@) { #{{{
	my %params=@_;
	my $form=$params{form};

	if (defined $form->field("do") && $form->field("do") eq "edit") {
		my $q=$params{cgi};
		my $session=$params{session};

		if ($form->submitted eq "Rename") {
			rename_start($q, $session, 0, $form->field("page"));
		}
		elsif ($form->submitted eq "Rename Attachment") {
			my @selected=$q->param("attachment_select");
			if (@selected > 1) {
				error(gettext("Only one attachment can be renamed at a time."));
			}
			elsif (! @selected) {
				error(gettext("Please select the attachment to rename."))
			}
			rename_start($q, $session, 1, $selected[0]);
		}
	}
} #}}}

my $renamesummary;

sub formbuilder_setup (@) { #{{{
	my %params=@_;
	my $form=$params{form};
	my $q=$params{cgi};

	if (defined $form->field("do") && $form->field("do") eq "edit") {
		# Rename button for the page, and also for attachments.
		push @{$params{buttons}}, "Rename";
		$form->tmpl_param("field-rename" => '<input name="_submit" type="submit" value="Rename Attachment" />');

		if (defined $renamesummary) {
			$form->tmpl_param(message => $renamesummary);
		}
	}
} #}}}

sub sessioncgi ($$) { #{{{
        my $q=shift;

	if ($q->param("do") eq 'rename') {
        	my $session=shift;
		my ($form, $buttons)=rename_form($q, $session, $q->param("page"));
		IkiWiki::decode_form_utf8($form);

		if ($form->submitted eq 'Cancel') {
			postrename($session);
		}
		elsif ($form->submitted eq 'Rename' && $form->validate) {
			# These untaints are safe because of the checks
			# performed in check_canrename below.
			my $src=$q->param("page");
			my $srcfile=IkiWiki::possibly_foolish_untaint($pagesources{$src});
			my $dest=IkiWiki::possibly_foolish_untaint(IkiWiki::titlepage($q->param("new_name")));

			my $destfile=$dest;
			if (! $q->param("attachment")) {
				my $type=$q->param('type');
				if (defined $type && length $type && $IkiWiki::hooks{htmlize}{$type}) {
					$type=IkiWiki::possibly_foolish_untaint($type);
				} else {
					my ($ext)=$srcfile=~/\.([^.]+)$/;
					$type=$ext;
				}
				
				$destfile.=".".$type;
			}

			check_canrename($src, $srcfile, $dest, $destfile,
				$q, $session, $q->param("attachment"));

			# Ensures that the dest directory exists and is ok.
			IkiWiki::prep_writefile($destfile, $config{srcdir});

			# Do rename, update other pages, and refresh site.
			IkiWiki::disable_commit_hook() if $config{rcs};
			require IkiWiki::Render;
			if ($config{rcs}) {
				IkiWiki::rcs_rename($srcfile, $destfile);
				IkiWiki::rcs_commit_staged(
					sprintf(gettext("rename %s to %s"), $srcfile, $destfile),
					$session->param("name"), $ENV{REMOTE_ADDR});
			}
			else {
				if (! rename("$config{srcdir}/$srcfile", "$config{srcdir}/$destfile")) {
					error("rename: $!");
				}
			}
			my @fixedlinks;
			if ($src ne $dest) {
				foreach my $page (keys %links) {
					my $needfix=0;
					foreach my $link (@{$links{$page}}) {
						my $bestlink=bestlink($page, $link);
						if ($bestlink eq $src) {
							$needfix=1;
							last;
						}
					}
					if ($needfix) {
						my $file=$pagesources{$page};
						my $oldcontent=readfile($config{srcdir}."/".$file);
						my $content=renamepage_hook($page, $src, $dest, $oldcontent);
						if ($oldcontent ne $content) {
							my $token=IkiWiki::rcs_prepedit($file);
							eval { writefile($file, $config{srcdir}, $content) };
							next if $@;
							my $conflict=IkiWiki::rcs_commit(
								$file,
								sprintf(gettext("update for rename of %s to %s"), $srcfile, $destfile),
								$token,
								$session->param("name"), 
								$ENV{REMOTE_ADDR}
							);
							push @fixedlinks, $page if ! defined $conflict;
						}
					}
				}
			}
			if ($config{rcs}) {
				IkiWiki::enable_commit_hook();
				IkiWiki::rcs_update();
			}
			IkiWiki::refresh();
			IkiWiki::saveindex();

			# Scan for any remaining broken links to $src.
			my @brokenlinks;
			if ($src ne $dest) {
				foreach my $page (keys %links) {
					my $broken=0;
					foreach my $link (@{$links{$page}}) {
						my $bestlink=bestlink($page, $link);
						if ($bestlink eq $src) {
							$broken=1;
							last;
						}
					}
					push @brokenlinks, $page if $broken;
				}
			}

			# Generate a rename summary, that will be shown at the top
			# of the edit template.
			my $template=template("renamesummary.tmpl");
			$template->param(src => $srcfile);
			$template->param(dest => $destfile);
			if ($src ne $dest) {
				$template->param(brokenlinks_checked => 1);
				$template->param(brokenlinks => [
					map {
						{
							page => htmllink($dest, $dest, $_,
									noimageinline => 1)
						}
					} @brokenlinks
				]);
				$template->param(fixedlinks => [
					map {
						{
							page => htmllink($dest, $dest, $_,
									noimageinline => 1)
						}
					} @fixedlinks
				]);
			}
			$renamesummary=$template->output;

			postrename($session, $src, $dest, $q->param("attachment"));
		}
		else {
			IkiWiki::showform($form, $buttons, $session, $q);
		}

		exit 0;
	}
} #}}}

sub renamepage_hook ($$$$) { #{{{
	my ($page, $src, $dest, $content)=@_;

	IkiWiki::run_hooks(renamepage => sub {
		$content=shift->(
			page => $page,
			oldpage => $src,
			newpage => $dest,
			content => $content,
		);
	});

	return $content;
}# }}}

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