Add "cascade" filter run prefix and use it to control view templates (#…

…6168)

* Initial Commit

* Set currentTiddler and ..currentTiddler for filter evaulation

* Precompile the filters for performance

* Add explicit test for empty result when no filter passes

* Use the cascade filter run prefix to choose the view template body template

* Use the cascade mechanism to choose between the edit and view templates

* Simplify cascade filter

Thanks @saqimtiaz

* Add control panel UI for inspecting the template cascades

* Refactor import listing and plugin listing as alternate body templates

As suggested by @pmario

* Refer to $:/core/ui/{View|Edit}Template via their associated config tiddlers

* Fix typo in previous commit

* Add demo of custom story tiddler template

* Tweak control panel wording

* Standardise "Story Tiddler Template" nomenclature

* Add a cascade for the editor template body

* Add a cascade for the view template title

* Avoid unwanted whitespace

* Add a cascade for dynamically choosing tiddler icons

core/language/en-GB/ControlPanel.multids

@@ -27,10 +27,15 @@ Basics/Tiddlers/Prompt: Number of tiddlers
 Basics/Title/Prompt: Title of this ~TiddlyWiki
 Basics/Username/Prompt: Username for signing edits
 Basics/Version/Prompt: ~TiddlyWiki version
+Cascades/Caption: Cascades
+Cascades/Hint: These global rules are used to dynamically choose certain templates. The result of the cascade is the result of the first filter in the sequence that returns a result
+Cascades/TagPrompt: Filters tagged <$macrocall $name="tag" tag=<<currentTiddler>>/>
 EditorTypes/Caption: Editor Types
 EditorTypes/Editor/Caption: Editor
 EditorTypes/Hint: These tiddlers determine which editor is used to edit specific tiddler types.
 EditorTypes/Type/Caption: Type
+EditTemplateBody/Caption: Edit Template Body
+EditTemplateBody/Hint: This rule cascade is used by the default edit template to dynamically choose the template for editing the body of a tiddler.
 Info/Caption: Info
 Info/Hint: Information about this TiddlyWiki
 KeyboardShortcuts/Add/Prompt: Type shortcut here
@@ -191,6 +196,8 @@ Settings/TitleLinks/Yes/Description: Display tiddler titles as links
 Settings/MissingLinks/Caption: Wiki Links
 Settings/MissingLinks/Hint: Choose whether to link to tiddlers that do not exist yet
 Settings/MissingLinks/Description: Enable links to missing tiddlers
+StoryTiddler/Caption: Story Tiddler
+StoryTiddler/Hint: This rule cascade is used to dynamically choose the template for displaying a tiddler in the story river.
 StoryView/Caption: Story View
 StoryView/Prompt: Current view:
 Stylesheets/Caption: Stylesheets
@@ -201,6 +208,8 @@ Theme/Caption: Theme
 Theme/Prompt: Current theme:
 TiddlerFields/Caption: Tiddler Fields
 TiddlerFields/Hint: This is the full set of TiddlerFields in use in this wiki (including system tiddlers but excluding shadow tiddlers).
+TiddlerIcon/Caption: Tiddler Icon
+TiddlerIcon/Hint: This rules cascade is used to dynamically choose the icon for a tiddler.
 Toolbars/Caption: Toolbars
 Toolbars/EditToolbar/Caption: Edit Toolbar
 Toolbars/EditToolbar/Hint: Choose which buttons are displayed for tiddlers in edit mode. Drag and drop to change the ordering
@@ -212,3 +221,7 @@ Toolbars/EditorToolbar/Hint: Choose which buttons are displayed in the editor to
 Toolbars/ViewToolbar/Caption: View Toolbar
 Toolbars/ViewToolbar/Hint: Choose which buttons are displayed for tiddlers in view mode. Drag and drop to change the ordering
 Tools/Download/Full/Caption: Download full wiki
+ViewTemplateBody/Caption: View Template Body
+ViewTemplateBody/Hint: This rule cascade is used by the default view template to dynamically choose the template for displaying the body of a tiddler.
+ViewTemplateTitle/Caption: View Template Title
+ViewTemplateTitle/Hint: This rule cascade is used by the default view template to dynamically choose the template for displaying the title of a tiddler.

core/modules/filterrunprefixes/cascade.js

@@ -0,0 +1,51 @@
+/*\
+title: $:/core/modules/filterrunprefixes/cascade.js
+type: application/javascript
+module-type: filterrunprefix
+\*/
+(function(){
+
+/*jslint node: true, browser: true */
+/*global $tw: false */
+"use strict";
+
+/*
+Export our filter prefix function
+*/
+exports.cascade = function(operationSubFunction,options) {
+	return function(results,source,widget) {
+		if(results.length !== 0) {
+			var filterList = operationSubFunction(source,widget),
+				filterFnList = [];
+			var inputResults = results.toArray();
+			results.clear();
+			$tw.utils.each(inputResults,function(title) {
+				var result = ""; // If no filter matches, we return an empty string
+				$tw.utils.each(filterList,function(filter,index) {
+					if(!filterFnList[index]) {
+						filterFnList[index] = options.wiki.compileFilter(filter);
+					}
+					var output = filterFnList[index](options.wiki.makeTiddlerIterator([title]),{
+							getVariable: function(name) {
+								switch(name) {
+									case "currentTiddler":
+										return "" + title;
+									case "..currentTiddler":
+										return widget.getVariable("currentTiddler");
+									default:
+										return widget.getVariable(name);
+								}
+							}
+						});
+					if(output.length !== 0) {
+						result = output[0];
+						return false;
+					}
+				});
+				results.push(result);
+			});
+		}
+	}
+};
+
+})();

core/ui/ControlPanel/Cascades.tid

@@ -0,0 +1,9 @@
+title: $:/core/ui/ControlPanel/Cascades
+tags: $:/tags/ControlPanel/Advanced
+caption: {{$:/language/ControlPanel/Cascades/Caption}}
+
+{{$:/language/ControlPanel/Cascades/Hint}}
+
+<div class="tc-control-panel">
+<$macrocall $name="tabs" tabsList="[all[shadows+tiddlers]tag[$:/tags/ControlPanel/Cascades]!has[draft.of]]" default="$:/core/ui/ControlPanel/StoryTiddler"/>
+</div>

core/ui/ControlPanel/Cascades/EditTemplateBody.tid

@@ -0,0 +1,9 @@
+title: $:/core/ui/ControlPanel/EditTemplateBody
+tags: $:/tags/ControlPanel/Cascade
+caption: {{$:/language/ControlPanel/EditTemplateBody/Caption}}
+
+\define lingo-base() $:/language/ControlPanel/EditTemplateBody/
+
+<<lingo Hint>>
+
+{{$:/tags/EditTemplateBodyFilter||$:/snippets/ListTaggedCascade}}

core/ui/ControlPanel/Cascades/StoryTiddler.tid

@@ -0,0 +1,9 @@
+title: $:/core/ui/ControlPanel/StoryTiddler
+tags: $:/tags/ControlPanel/Cascades
+caption: {{$:/language/ControlPanel/StoryTiddler/Caption}}
+
+\define lingo-base() $:/language/ControlPanel/StoryTiddler/
+
+<<lingo Hint>>
+
+{{$:/tags/StoryTiddlerTemplateFilter||$:/snippets/ListTaggedCascade}}

core/ui/ControlPanel/Cascades/TiddlerIcon.tid

@@ -0,0 +1,9 @@
+title: $:/core/ui/ControlPanel/TiddlerIcon
+tags: $:/tags/ControlPanel/Cascades
+caption: {{$:/language/ControlPanel/TiddlerIcon/Caption}}
+
+\define lingo-base() $:/language/ControlPanel/TiddlerIcon/
+
+<<lingo Hint>>
+
+{{$:/tags/TiddlerIconFilter||$:/snippets/ListTaggedCascade}}

core/ui/ControlPanel/Cascades/ViewTemplateBody.tid

@@ -0,0 +1,9 @@
+title: $:/core/ui/ControlPanel/ViewTemplateBody
+tags: $:/tags/ControlPanel/Cascades
+caption: {{$:/language/ControlPanel/ViewTemplateBody/Caption}}
+
+\define lingo-base() $:/language/ControlPanel/ViewTemplateBody/
+
+<<lingo Hint>>
+
+{{$:/tags/ViewTemplateBodyFilter||$:/snippets/ListTaggedCascade}}

core/ui/ControlPanel/Cascades/ViewTemplateTitle.tid

@@ -0,0 +1,9 @@
+title: $:/core/ui/ControlPanel/ViewTemplateTitle
+tags: $:/tags/ControlPanel/Cascades
+caption: {{$:/language/ControlPanel/ViewTemplateTitle/Caption}}
+
+\define lingo-base() $:/language/ControlPanel/ViewTemplateTitle/
+
+<<lingo Hint>>
+
+{{$:/tags/ViewTemplateTitleFilter||$:/snippets/ListTaggedCascade}}

core/ui/EditTemplate/body.tid

@@ -1,56 +1,4 @@
 title: $:/core/ui/EditTemplate/body
 tags: $:/tags/EditTemplate
 
-\define lingo-base() $:/language/EditTemplate/Body/
-\define config-visibility-title()
-$:/config/EditorToolbarButtons/Visibility/$(currentTiddler)$
-\end
-
-\define importFileActions()
-<$action-popup $state=<<importState>> $coords="(0,0,0,0)" $floating="yes"/>
-\end
-
-<$list filter="[all[current]has[_canonical_uri]]">
-
-<div class="tc-message-box">
-
-<<lingo External/Hint>>
-
-<a href={{!!_canonical_uri}}><$text text={{!!_canonical_uri}}/></a>
-
-<$edit-text field="_canonical_uri" class="tc-edit-fields" tabindex={{$:/config/EditTabIndex}} cancelPopups="yes"></$edit-text>
-
-</div>
-
-</$list>
-
-<$set name="edit-preview-state" value={{{ [{$:/config/ShowEditPreview/PerTiddler}!match[yes]then[$:/state/showeditpreview]] :else[<qualify "$:/state/showeditpreview">] }}}>
-<$list filter="[all[current]!has[_canonical_uri]]">
-<$vars importTitle=<<qualify $:/ImportImage>> importState=<<qualify $:/state/ImportImage>> >
-<$dropzone importTitle=<<importTitle>> autoOpenOnImport="no" contentTypesFilter={{$:/config/Editor/ImportContentTypesFilter}} class="tc-dropzone-editor" enable={{{ [{$:/config/DragAndDrop/Enable}match[no]] :else[subfilter{$:/config/Editor/EnableImportFilter}then[yes]else[no]] }}} filesOnly="yes" actions=<<importFileActions>> ><$reveal stateTitle=<<edit-preview-state>> type="match" text="yes">
-<div class="tc-tiddler-preview">
-
-<$transclude tiddler="$:/core/ui/EditTemplate/body/editor" mode="inline"/>
-
-<div class="tc-tiddler-preview-preview">
-
-<$transclude tiddler={{$:/state/editpreviewtype}} mode="inline">
-
-<$transclude tiddler="$:/core/ui/EditTemplate/body/preview/output" mode="inline"/>
-
-</$transclude>
-
-</div>
-
-</div>
-</$reveal>
-
-<$reveal stateTitle=<<edit-preview-state>> type="nomatch" text="yes">
-
-<$transclude tiddler="$:/core/ui/EditTemplate/body/editor" mode="inline"/>
-
-</$reveal>
-</$dropzone>
-</$vars>
-</$list>
-</$set>
+<$transclude tiddler={{{ [<currentTiddler>] :cascade[all[shadows+tiddlers]tag[$:/tags/EditTemplateBodyFilter]get[text]] :and[!is[blank]else[$:/core/ui/EditTemplate/body/default]] }}} />

core/ui/EditTemplate/body/canonical-uri.tid

@@ -0,0 +1,13 @@
+title: $:/core/ui/EditTemplate/body/canonical-uri
+
+\define lingo-base() $:/language/EditTemplate/Body/
+
+<div class="tc-message-box">
+
+<<lingo External/Hint>>
+
+<a href={{!!_canonical_uri}}><$text text={{!!_canonical_uri}}/></a>
+
+<$edit-text field="_canonical_uri" class="tc-edit-fields" tabindex={{$:/config/EditTabIndex}} cancelPopups="yes"></$edit-text>
+
+</div>

core/ui/EditTemplate/body/default.tid

@@ -0,0 +1,38 @@
+title: $:/core/ui/EditTemplate/body/default
+
+\define config-visibility-title()
+$:/config/EditorToolbarButtons/Visibility/$(currentTiddler)$
+\end
+
+\define importFileActions()
+<$action-popup $state=<<importState>> $coords="(0,0,0,0)" $floating="yes"/>
+\end
+
+<$set name="edit-preview-state" value={{{ [{$:/config/ShowEditPreview/PerTiddler}!match[yes]then[$:/state/showeditpreview]] :else[<qualify "$:/state/showeditpreview">] }}}>
+<$vars importTitle=<<qualify $:/ImportImage>> importState=<<qualify $:/state/ImportImage>> >
+<$dropzone importTitle=<<importTitle>> autoOpenOnImport="no" contentTypesFilter={{$:/config/Editor/ImportContentTypesFilter}} class="tc-dropzone-editor" enable={{{ [{$:/config/DragAndDrop/Enable}match[no]] :else[subfilter{$:/config/Editor/EnableImportFilter}then[yes]else[no]] }}} filesOnly="yes" actions=<<importFileActions>> ><$reveal stateTitle=<<edit-preview-state>> type="match" text="yes">
+<div class="tc-tiddler-preview">
+
+<$transclude tiddler="$:/core/ui/EditTemplate/body/editor" mode="inline"/>
+
+<div class="tc-tiddler-preview-preview">
+
+<$transclude tiddler={{$:/state/editpreviewtype}} mode="inline">
+
+<$transclude tiddler="$:/core/ui/EditTemplate/body/preview/output" mode="inline"/>
+
+</$transclude>
+
+</div>
+
+</div>
+</$reveal>
+
+<$reveal stateTitle=<<edit-preview-state>> type="nomatch" text="yes">
+
+<$transclude tiddler="$:/core/ui/EditTemplate/body/editor" mode="inline"/>
+
+</$reveal>
+</$dropzone>
+</$vars>
+</$set>

core/ui/ListTaggedCascade.tid

@@ -0,0 +1,14 @@
+title: $:/snippets/ListTaggedCascade
+
+{{||$:/language/ControlPanel/Cascades/TagPrompt}}
+
+<ol>
+<$list filter="[all[shadows+tiddlers]tag<currentTiddler>]">
+<li>
+<div>
+<$link><$text text=<<currentTiddler>>/></$link>
+</div>
+<$codeblock code={{!!text}}/>
+</li>
+</$list>
+</ol>

core/ui/PageTemplate/story.tid

@@ -14,7 +14,7 @@ tags: $:/tags/PageTemplate
 
 </section>
 
-<$list filter="[list[$:/StoryList]]" history="$:/HistoryList" template={{$:/config/ui/ViewTemplate}} editTemplate={{$:/config/ui/EditTemplate}} storyview={{$:/view}} emptyMessage={{$:/config/EmptyStoryMessage}}/>
+<$list filter="[list[$:/StoryList]]" history="$:/HistoryList" template="$:/core/ui/StoryTiddlerTemplate" storyview={{$:/view}} emptyMessage={{$:/config/EmptyStoryMessage}}/>
 
 <section class="story-frontdrop">
 

core/ui/StoryTiddlerTemplate.tid

@@ -0,0 +1,3 @@
+title: $:/core/ui/StoryTiddlerTemplate
+
+<$transclude tiddler={{{ [<currentTiddler>] :cascade[all[shadows+tiddlers]tag[$:/tags/StoryTiddlerTemplateFilter]get[text]] :and[!is[blank]else{$:/config/ui/ViewTemplate}] }}} />

core/ui/TagPickerTagTemplate.tid

@@ -16,7 +16,7 @@ title: $:/core/ui/TagPickerTagTemplate
 <$set name="backgroundColor" value={{!!color}}>
 <$wikify name="foregroundColor" text="""<$macrocall $name="contrastcolour" target={{!!color}} fallbackTarget=<<fallbackTarget>> colourA=<<colourA>> colourB=<<colourB>>/>""">
 <span class="tc-tag-label tc-btn-invisible" style=<<tag-pill-styles>>>
-<$transclude tiddler={{!!icon}}/><$view field="title" format="text"/>
+{{||$:/core/ui/TiddlerIcon}}<$view field="title" format="text"/>
 </span>
 </$wikify>
 </$set>

core/ui/TagTemplate.tid

@@ -3,7 +3,7 @@ title: $:/core/ui/TagTemplate
 \whitespace trim
 <span class="tc-tag-list-item" data-tag-title=<<currentTiddler>>>
 <$set name="transclusion" value=<<currentTiddler>>>
-<$macrocall $name="tag-pill-body" tag=<<currentTiddler>> icon={{!!icon}} colour={{!!color}} palette={{$:/palette}} element-tag="""$button""" element-attributes="""popup=<<qualify "$:/state/popup/tag">> dragFilter='[all[current]tagging[]]' tag='span'"""/>
+<$macrocall $name="tag-pill-body" tag=<<currentTiddler>> colour={{!!color}} palette={{$:/palette}} element-tag="""$button""" element-attributes="""popup=<<qualify "$:/state/popup/tag">> dragFilter='[all[current]tagging[]]' tag='span'"""/>
 <$reveal state=<<qualify "$:/state/popup/tag">> type="popup" position="below" animate="yes" class="tc-drop-down">
 <$set name="tv-show-missing-links" value="yes">
 <$transclude tiddler="$:/core/ui/ListItemTemplate"/>

core/ui/TiddlerIcon.tid

@@ -0,0 +1,15 @@
+title: $:/core/ui/TiddlerIcon
+
+\whitespace trim
+\define title-styles()
+fill:$(foregroundColor)$;
+\end
+<$let tiddlerIcon={{{ [<currentTiddler>] :cascade[all[shadows+tiddlers]tag[$:/tags/TiddlerIconFilter]get[text]] }}}>
+<$list filter="[<tiddlerIcon>!is[blank]]" variable="ignore">
+<$let foregroundColor={{!!color}}>
+<span class=<<iconSpanClass>> style=<<title-styles>>>
+<$transclude tiddler=<<tiddlerIcon>>/>
+</span>
+</$let>
+</$list>
+</$let>

core/ui/ViewTemplate/body.tid

@@ -3,14 +3,6 @@ tags: $:/tags/ViewTemplate
 
 <$reveal tag="div" class="tc-tiddler-body" type="nomatch" stateTitle=<<folded-state>> text="hide" retain="yes" animate="yes">
 
-<$list filter="[all[current]!has[plugin-type]!field:hide-body[yes]]">
-
-<$transclude>
-
-<$transclude tiddler="$:/language/MissingTiddler/Hint"/>
-
-</$transclude>
-
-</$list>
+<$transclude tiddler={{{ [<currentTiddler>] :cascade[all[shadows+tiddlers]tag[$:/tags/ViewTemplateBodyFilter]get[text]] :and[!is[blank]else[$:/core/ui/ViewTemplate/body/default]] }}} />
 
 </$reveal>

core/ui/ViewTemplate/body/blank.tid

@@ -0,0 +1,3 @@
+title: $:/core/ui/ViewTemplate/body/blank
+
+<!-- Intentionally blank -->

core/ui/ViewTemplate/body/code.tid

@@ -0,0 +1,3 @@
+title: $:/core/ui/ViewTemplate/body/code
+
+<$codeblock code={{{ [<currentTiddler>get[text]] }}} language={{{ [<currentTiddler>get[type]else[text/vnd.tiddlywiki]] }}}/>

core/ui/ViewTemplate/body/default.tid

@@ -0,0 +1,7 @@
+title: $:/core/ui/ViewTemplate/body/default
+
+<$transclude>
+
+<$transclude tiddler="$:/language/MissingTiddler/Hint"/>
+
+</$transclude>

core/ui/ViewTemplate/import.tid → core/ui/ViewTemplate/body/import.tid

@@ -1,5 +1,4 @@
-title: $:/core/ui/ViewTemplate/import
-tags: $:/tags/ViewTemplate
+title: $:/core/ui/ViewTemplate/body/import
 
 \define lingo-base() $:/language/Import/
 

core/ui/ViewTemplate/body/plugin.tid

@@ -0,0 +1,10 @@
+title: $:/core/ui/ViewTemplate/body/plugin
+
+<div class="tc-tiddler-plugin-info">
+<$let plugin-type={{!!plugin-type}}
+	default-popup-state="yes"
+	qualified-state=<<qualify "$:/state/plugin-info">>
+>
+{{||$:/core/ui/Components/plugin-info}}
+</$let>
+</div>