Comments plugin: several enhancements

As proposed in #3378

* Experimental support for comments on the entire wiki (enable in the plugin config panel). Implemented as comments on $:/SiteTitle, with the comments appearing at the top of the story river
* Refactor the "add comment" button actions so that they can be reused
* Refactor the comment toolbar to be extensible via a system tag
* Add an $:/AdvancedSearch canned filter for accessing all comments

plugins/tiddlywiki/comments/above-story.tid

@@ -0,0 +1,8 @@
+title: $:/plugins/tiddlywiki/comments/above-story
+tags: $:/tags/AboveStory
+
+<$reveal state="$:/config/Comments/EnableWikiComments" type="match" text="yes" default="no">
+<$tiddler tiddler="$:/SiteTitle">
+<$transclude tiddler="$:/plugins/tiddlywiki/comments/comments-template" mode="inline"/>
+</$tiddler>
+</$reveal>

plugins/tiddlywiki/comments/add-comment-button.tid

@@ -1,10 +1,7 @@
 title: $:/plugins/tiddlywiki/comments/add-comment-button
 
 <$reveal state="$:/status/IsReadOnly" type="match" text="no" default="no" tag="div" class="tc-comment-button">
-<$button class="tc-btn-invisible">
-<$set name="username" value={{$:/status/UserName}} emptyValue="(anonymous)">
-<$action-createtiddler $basetitle={{{ [[Comment by ']addsuffix<username>addsuffix[' on ']addsuffix<currentTiddler>addsuffix[']] }}} comment-target=<<currentTiddler>> text="" edit-mode="yes"/>
-</$set>
+<$button class="tc-btn-invisible" actions={{$:/plugins/tiddlywiki/comments/add-comment-button}}>
 add comment {{$:/core/images/add-comment}}
 </$button>
 </$reveal>

plugins/tiddlywiki/comments/comments-template.tid

@@ -7,30 +7,9 @@ title: $:/plugins/tiddlywiki/comments/comments-template
 <div class="tc-comment-entry">
 <div class="tc-comment-entry-heading">
 <$link>{{!!creator}} at <$view field="modified" format="date" template="0hh:0mm:0ss DDD DDth MMM YYYY"/></$link>
-<$reveal state="$:/status/IsReadOnly" type="match" text="no" default="no" tag="span">
-<$reveal type="match" state="!!edit-mode" text="yes">
-<$button>
-<$action-setfield $tiddler=<<currentTiddler>> $field="edit-mode" $value="no"/>
-<$action-setfield $tiddler=<<currentTiddler>> $field="text" $value={{!!saved-text}}/>
-cancel
-</$button>
-<$button>
-<$action-deletetiddler $tiddler=<<currentTiddler>>/>
-delete
-</$button>
-<$button>
-<$action-setfield $tiddler=<<currentTiddler>> $field="edit-mode" $value="no"/>
-save
-</$button>
-</$reveal>
-<$reveal type="nomatch" state="!!edit-mode" text="yes">
-<$button>
-<$action-setfield $tiddler=<<currentTiddler>> $field="edit-mode" $value="yes"/>
-<$action-setfield $tiddler=<<currentTiddler>> $field="saved-text" $value={{!!text}}/>
-edit
-</$button>
-</$reveal>
-</$reveal>
+<$list filter="[all[shadows+tiddlers]tag[$:/tags/CommentToolbarButton]!has[draft.of]]" variable="listItem">
+<$transclude tiddler=<<listItem>> mode="inline"/>
+</$list>
 </div>
 <div class="tc-comment-entry-body">
 <$reveal type="match" state="!!edit-mode" text="yes">

plugins/tiddlywiki/comments/config.tid

@@ -7,6 +7,12 @@ $description$
 </$button>
 \end
 
+! Wiki Comments
+
+<$checkbox tiddler="$:/config/Comments/EnableWikiComments" field="text" checked="yes" unchecked="no" default="no"> <$link to="$:/config/Comments/EnableWikiComments">Allow wiki-level comments as well as tiddler comments</$link> </$checkbox>
+
+! Tiddler Comments
+
 This filter expression determines which tiddlers will have commenting enabled:
 
 <$edit-text tiddler="$:/config/Comments/EnableFilter" tag="input"/>

plugins/tiddlywiki/comments/filter-all-comments.tid

@@ -0,0 +1,5 @@
+title: $:/plugins/tiddlywiki/comments/filter-all-comments
+tags: $:/tags/Filter
+filter: [has[comment-target]!sort[modified]]
+description: All comments
+

plugins/tiddlywiki/comments/readme.tid

@@ -8,3 +8,4 @@ This plugin provides a simple means for adding threaded comments to tiddlers.
 * Comments are attributed to the username stored in the system tiddler [[$:/status/UserName]]
 * By default, comments are available on all non-system tiddlers. The ''config'' tab lets you customise which tiddlers can accept comments by specifying a filter extension
 * The buttons for adding and editing comments are only available if the system tiddler [[$:/status/IsReadOnly]] is not set to `yes`
+* Use the "All comments" option in the $:/AdvancedSearch ''Filter'' tab to see or export all comments

plugins/tiddlywiki/comments/sidebar-segment.tid

@@ -0,0 +1,9 @@
+title: $:/plugins/tiddlywiki/comments/sidebar-segment
+tags: $:/tags/SideBarSegment
+list-after: $:/core/ui/SideBarSegments/site-subtitle
+
+<$reveal state="$:/config/Comments/EnableWikiComments" type="match" text="yes" default="no">
+<$tiddler tiddler="$:/SiteTitle">
+<$transclude tiddler="$:/plugins/tiddlywiki/comments/add-comment-button" mode="inline"/>
+</$tiddler>
+</$reveal>

plugins/tiddlywiki/comments/styles.tid

@@ -17,6 +17,11 @@ tags: [[$:/tags/Stylesheet]]
 	text-align: right;
 }
 
+.tc-sidebar-scrollable .tc-comment-button button {
+	width: auto;
+	text-align: right;
+}
+
 .tc-comment-button button svg {
 	fill: #26cb56;
 	height: 2em;

plugins/tiddlywiki/comments/tagsCommentToolbarButton.tid

@@ -0,0 +1,2 @@
+title: $:/tags/CommentToolbarButton
+list: [[$:/plugins/tiddlywiki/comments/toolbar-button-cancel]] [[$:/plugins/tiddlywiki/comments/toolbar-button-delete]] [[$:/plugins/tiddlywiki/comments/toolbar-button-save]] [[$:/plugins/tiddlywiki/comments/toolbar-button-edit]] 

plugins/tiddlywiki/comments/toolbar-button-cancel.tid

@@ -0,0 +1,12 @@
+title: $:/plugins/tiddlywiki/comments/toolbar-button-cancel
+tags: $:/tags/CommentToolbarButton
+
+<$reveal state="$:/status/IsReadOnly" type="match" text="no" default="no" tag="span">
+<$reveal type="match" state="!!edit-mode" text="yes">
+<$button>
+<$action-setfield $tiddler=<<currentTiddler>> $field="edit-mode" $value="no"/>
+<$action-setfield $tiddler=<<currentTiddler>> $field="text" $value={{!!saved-text}}/>
+cancel
+</$button>
+</$reveal>
+</$reveal>

plugins/tiddlywiki/comments/toolbar-button-delete.tid

@@ -0,0 +1,11 @@
+title: $:/plugins/tiddlywiki/comments/toolbar-button-delete
+tags: $:/tags/CommentToolbarButton
+
+<$reveal state="$:/status/IsReadOnly" type="match" text="no" default="no" tag="span">
+<$reveal type="match" state="!!edit-mode" text="yes">
+<$button>
+<$action-deletetiddler $tiddler=<<currentTiddler>>/>
+delete
+</$button>
+</$reveal>
+</$reveal>

plugins/tiddlywiki/comments/toolbar-button-edit.tid

@@ -0,0 +1,12 @@
+title: $:/plugins/tiddlywiki/comments/toolbar-button-edit
+tags: $:/tags/CommentToolbarButton
+
+<$reveal state="$:/status/IsReadOnly" type="match" text="no" default="no" tag="span">
+<$reveal type="nomatch" state="!!edit-mode" text="yes">
+<$button>
+<$action-setfield $tiddler=<<currentTiddler>> $field="edit-mode" $value="yes"/>
+<$action-setfield $tiddler=<<currentTiddler>> $field="saved-text" $value={{!!text}}/>
+edit
+</$button>
+</$reveal>
+</$reveal>

plugins/tiddlywiki/comments/toolbar-button-save.tid

@@ -0,0 +1,11 @@
+title: $:/plugins/tiddlywiki/comments/toolbar-button-save
+tags: $:/tags/CommentToolbarButton
+
+<$reveal state="$:/status/IsReadOnly" type="match" text="no" default="no" tag="span">
+<$reveal type="match" state="!!edit-mode" text="yes">
+<$button>
+<$action-setfield $tiddler=<<currentTiddler>> $field="edit-mode" $value="no"/>
+save
+</$button>
+</$reveal>
+</$reveal>