+
+----
+
+I've written a plugin to implement access keys, configured using a wiki page similar to [[shortcuts]]. It works for links and most form submit buttons.
+
+As I am new to ikiwiki plugin writing, feedback is greatly appreciated.
+
+[[!toggle id="accesskeys" text="Toggle: accesskeys.pm"]]
+
+[[!toggleable id="accesskeys" text="""
+
+ #!/usr/bin/perl
+
+ package IkiWiki::Plugin::accesskeys;
+
+ use warnings;
+ use strict;
+ use IkiWiki 3.00;
+ use CGI::FormBuilder;
+
+ =head1 NAME
+
+ accesskeys.pm - IkiWiki module to implement access keys (keyboard shortcuts)
+
+ =head1 VERSION
+
+ v.5.0 - initial version
+
+ =head1 DESCRIPTION
+
+ Access keys are defined on a page called B<accesskeys>, using the C<accesskey> directive.
+ Example:
+
+ [[!accesskey command="Save Page" key="s"]]
+
+ B<command> may contain only alphanumeric characters (and spaces), and must be a complete
+ match to the target link or submit button's display name.
+
+ B<key> may only be a single alphanumeric character.
+
+ The access key is applied to the first matching link on a page (including header), or the
+ first matching submit button in the @buttons array.
+
+ The wiki must be completely rebuilt every time the B<accesskeys> page changes.
+
+ =head2 Sample accesskeys page
+
+ [[!if test="enabled(accesskeys)"
+ then="This wiki has accesskeys **enabled**."
+ else="This wiki has accesskeys **disabled**."]]
+
+ This page controls what access keys the wiki uses.
+
+ * [[!accesskey command="Save Page" key="s"]]
+ * [[!accesskey command="Cancel" key="c"]]
+ * [[!accesskey command="Preview" key="v"]]
+ * [[!accesskey command="Edit" key="e"]]
+ * [[!accesskey command="RecentChanges" key="c"]]
+ * [[!accesskey command="Preferences" key="p"]]
+ * [[!accesskey command="Discussion" key="d"]]
+
+ =head1 IMPLEMENTATION
+
+ This plugin uses the following flow:
+
+ =over 1
+
+ =item 1. Override default CGI::FormBuilder::submit function
+
+ FormBuilder does not support any arbitrary modification of it's submit buttons, so
+ in order to add the necessary attributes you have to intercept the internal function
+ call which generates the formatted html for the submit buttons. Not pretty, but it
+ works.
+
+ =item 2. Get list of keys
+
+ During the B<checkconfig> stage the B<accesskeys> source file is read (default
+ F<accesskeys.mdwn>) to generate a list of defined keys.
+
+ =item 3. Insert keys (links)
+
+ Keys are inserted into links during the format stage. All defined commands are checked
+ against the page's links and if there is a match the key is inserted. Only the first
+ match for each command is processed.
+
+ =item 4. Insert keys (FormBuilder buttons)
+
+ FormBuilder pages are intercepted during formatting. Keys are inserted as above.
+
+ =back
+
+ =head1 TODO
+
+ =over 1
+
+ =item * non-existant page links ex: ?Discussion
+
+ =item * Support non-submit array buttons (like those added after the main group for attachments)
+
+ =item * Support form fields (search box)
+
+ =back
+
+ =cut
+
+ #=head1 HISTORY
+
+ =head1 AUTHOR
+
+ Written by Damian Small.
+
+ =cut
+
+ my %accesskeys = ();
+
+ # Initialize original function pointer to FormBuilder::submit
+ my $original_submit_function = \&{'CGI::FormBuilder::submit'};
+ # Override default submit function in FormBuilder
+ {
+ no strict 'refs';
+ no warnings;
+ *{'CGI::FormBuilder::submit'} = \&submit_override;
+ }
+
+ sub submit_override {
+ # Call the original function, and get the results
+ my $contents = $original_submit_function->(@_);
+
+ # Hack the results to add accesskeys
+ foreach my $buttonName (keys %accesskeys) {
+ $contents =~ s/(<input id="_submit[^>]+ value="$buttonName")( \/>)/$1 title="$buttonName [$accesskeys{$buttonName}]" accesskey="$accesskeys{$buttonName}"$2/;
+ }
+
+ return $contents;
+ }
+
+ sub import {
+ hook(type => "getsetup", id => "accesskeys", call => \&getsetup);
+ hook(type => "checkconfig", id => "accesskeys", call => \&checkconfig);
+ hook(type => "preprocess", id => "accesskey", call => \&preprocess_accesskey);
+ hook(type => "format", id => "accesskeys", call => \&format);
+ }
+
+ sub getsetup () {
+ return
+ plugin => {
+ safe => 1,
+ rebuild => 1,
+ section => "widget",
+ },
+ }
+
+ sub checkconfig () {
+ if (defined $config{srcdir} && length $config{srcdir}) {
+ # Preprocess the accesskeys page to get all the access keys
+ # defined before other pages are rendered.
+ my $srcfile=srcfile("accesskeys.".$config{default_pageext}, 1);
+ if (! defined $srcfile) {
+ $srcfile=srcfile("accesskeys.mdwn", 1);
+ }
+ if (! defined $srcfile) {
+ print STDERR sprintf(gettext("accesskeys plugin will not work without %s"),
+ "accesskeys.".$config{default_pageext})."\n";
+ }
+ else {
+ IkiWiki::preprocess("accesskeys", "accesskeys", readfile($srcfile));
+ }
+ }
+ }
+
+ sub preprocess_accesskey (@) {
+ my %params=@_;
+
+ if (! defined $params{command} || ! defined $params{key}) {
+ error gettext("missing command or key parameter");
+ }
+
+ # check the key
+ if ($params{key} !~ /^[a-zA-Z0-9]$/) {
+ error gettext("key parameter is not a single character");
+ }
+ # check the command
+ if ($params{command} !~ /^[a-zA-Z0-9 _]+$/) {
+ error gettext("command parameter is not an alphanumeric string");
+ }
+ # Add the access key:
+ $accesskeys{$params{command}} = $params{key};
+
+ return sprintf(gettext("[%s] is the access key for command '<i>%s</i>'"), $params{key}, $params{command});
+ }
+
+ sub format (@) {
+ my %params = @_;
+ my $contents = $params{content};
+
+ # If the accesskey page changes, all pages will need to be updated
+ #debug("Adding dependency: for " . $params{page} . " to AccessKeys");
+ add_depends($params{page}, "AccessKeys");
+
+ # insert access keys
+ foreach my $command (keys %accesskeys) {
+ $contents =~ s/(<a href=[^>]+)(>$command<\/a>)/$1 accesskey="$accesskeys{$command}"$2/;
+ }
+ # may need special handling for non-existant discussion links (and possibly other similar cases?)
+ #$contents =~ s/(<a href=[^>]+)(>\?<\/a>Discussion)/$1 accesskey="d"$2/;
+
+ return $contents;
+ }
+
+ 1
+
+
+[[!toggle id="accesskeys" text="hide accesskeys.pm"]]
+"""]]
+
+--[[DamianSmall]]
+
+[[!tag wishlist]]