From cb3741c8ee795d5c7b3c2fbc5299c841c269a4cc Mon Sep 17 00:00:00 2001
From: Jeremy Ruston <jeremy@osmosoft.com>
Date: Tue, 16 Oct 2012 18:50:32 +0100
Subject: [PATCH] Refactored list macro

Now does selective refreshing, improving performance in several areas.
(Classic TW always refreshed lists in their entirety). A bit more to
do, but the plan is that this can replace the story macro, too
---
 core/modules/macros/list.js | 188 +++++++++++++++++++++++++-----------
 1 file changed, 134 insertions(+), 54 deletions(-)

diff --git a/core/modules/macros/list.js b/core/modules/macros/list.js
index df26da6ff..e985d63ce 100644
--- a/core/modules/macros/list.js
+++ b/core/modules/macros/list.js
@@ -12,73 +12,153 @@ List macro
 /*global $tw: false */
 "use strict";
 
-var handlers = {
-	all: function(wiki) {
-		return wiki.getTiddlers("title","excludeLists");
-	},
-	missing: function(wiki) {
-		return wiki.getMissingTitles();
-	},
-	orphans: function(wiki) {
-		return wiki.getOrphanTitles();
-	},
-	shadowed: function(wiki) {
-		return wiki.getShadowTitles();
-	},
-	touched: function(wiki) {
-		// Server syncing isn't implemented yet
-		return [];
-	},
-	filter: function(wiki) {
-		// Filters aren't implemented yet
-		return [];
-	}
-};
-
 exports.info = {
 	name: "list",
 	dependentAll: true, // Tiddlers containing <<list>> macro are dependent on every tiddler
 	params: {
-		type: {byName: "default", type: "text"},
+		type: {byPos: 0, type: "text"},
+		filter: {byName: true, type: "filter"},
 		template: {byName: true, type: "tiddler"},
+		templateText: {byName: true, type: "text"},
+		editTemplate: {byName: true, type: "tiddler"},
+		editTemplateText: {byName: true, type: "text"},
 		emptyMessage: {byName: true, type: "text"}
 	}
 };
 
 exports.executeMacro = function() {
-	var templateType = "text/x-tiddlywiki",
-		templateText = "<<view title link>>",
-		template = this.params.template ? this.wiki.getTiddler(this.params.template) : null,
-		children = [],
-		t,
-		parents = this.parents,
-		attributes = {};
-	if(template) {
-		parents = parents.slice(0);
-		parents.push(template.title);
-		templateType = template.type;
-		templateText = template.text;
-	}
-	var handler = handlers[this.params.type];
-	handler = handler || handlers.all;
-	var tiddlers = handler(this.wiki,this.tiddlerTitle);
+	// Get the list of tiddlers object
+	this.getTiddlerList();
+	// Create the list frame element
+	var attributes = {"class": ["tw-list-frame"]};
 	if(this.classes) {
-		attributes["class"] = this.classes.slice(0);
+		$tw.utils.pushTop(attributes["class"],this.classes);
 	}
-	if(tiddlers.length === 0) {
-		return $tw.Tree.Text(this.params.emptyMessage || "");
-	} else {
-		var templateTree = this.wiki.parseText(templateType,templateText).tree;
-		for(t=0; t<tiddlers.length; t++) {
-			var cloneTemplate = [];
-			for(var c=0; c<templateTree.length; c++) {
-				cloneTemplate.push(templateTree[c].clone());
-			}
-			var listNode = $tw.Tree.Element("li",null,cloneTemplate);
-			listNode.execute(parents,tiddlers[t]);
-			children.push(listNode);
+	this.listFrame = $tw.Tree.Element("div",attributes,[]);
+	// Create each list element
+	for(var t=0; t<this.list.length; t++) {
+		this.listFrame.children.push(this.createListElement(this.list[t]));
+	}
+	return this.listFrame;
+};
+
+exports.getTiddlerList = function() {
+	this.list = this.wiki.filterTiddlers(this.params.filter,this.tiddlerTitle);
+};
+
+/*
+Create a list element representing a given tiddler
+*/
+exports.createListElement = function(title) {
+	var node = this.createListElementMacro(title),
+		eventHandler = {handleEvent: function(event) {
+			// Add context information to the event
+			event.navigateFromListElement = node;
+			event.navigateFromTitle = title;
+			return true;
+		}};
+	node.execute(this.parents,this.tiddlerTitle);
+	var listElement = $tw.Tree.Element("div",{"class": ["tw-list-element"]},[node],{
+			events: ["tw-navigate","tw-EditTiddler","tw-SaveTiddler","tw-CloseTiddler"],
+			eventHandler: eventHandler
+		});
+	// Save our data inside the list element node
+	listElement.listElementInfo = {title: title};
+	return listElement;
+};
+
+/*
+Create the tiddler macro needed to represent a given tiddler
+*/
+exports.createListElementMacro = function(title) {
+	// Check if the tiddler is a draft
+	var tiddler = this.wiki.getTiddler(title),
+		draft = tiddler ? $tw.utils.hop(tiddler.fields,"draft-of") : false;
+	// Figure out the template to use
+	var template = this.params.template,
+		templateText = this.params.templateText;
+	if(draft && this.hasParameter("editTemplate")) {
+		template = this.params.editTemplate;
+	}
+	if(draft && this.hasParameter("editTemplateText")) {
+		template = this.params.editTemplateText;
+	}
+	// Create the tiddler macro
+	return $tw.Tree.Macro("tiddler",{
+			srcParams: {
+				target: title,
+				template: template,
+				templateText: templateText
+			},
+			wiki: this.wiki
+		});
+};
+
+/*
+Remove a list element from the list, along with the attendant DOM nodes
+*/
+exports.removelistElement = function(index) {
+	// Get the list element
+	var listElement = this.listFrame.children[index];
+	// Remove the dom node
+	listElement.domNode.parentNode.removeChild(listElement.domNode);
+	// Then delete the actual renderer node
+	this.listFrame.children.splice(index,1);
+};
+
+/*
+Return the index of the list element that corresponds to a particular title
+startIndex: index to start search (use zero to search from the top)
+title: tiddler title to seach for
+*/
+exports.findListElementByTitle = function(startIndex,title) {
+	while(startIndex < this.listFrame.children.length) {
+		if(this.listFrame.children[startIndex].listElementInfo.title === title) {
+			return startIndex;
+		}
+		startIndex++;
+	}
+	return undefined;
+};
+
+/*
+Selectively update the list in response to changes in tiddlers
+*/
+exports.refreshInDom = function(changes) {
+	// If any of our parameters have changed we'll have to completely re-execute the macro
+	var paramNames = ["template","editTemplate"];
+	for(var t=0; t<paramNames.length; t++) {
+		if(this.hasParameter(paramNames[t]) && $tw.utils.hop(changes,this.params[paramNames[t]])) {
+			this.reexecuteInDom();
+			return;
+		}
+	}
+	// Get the list of tiddlers
+	this.getTiddlerList();
+	// Step through the list and adjust our child list elements appropriately
+	for(t=0; t<this.list.length; t++) {
+		// Check to see if the list element is already there
+		var index = this.findListElementByTitle(t,this.list[t]);
+		if(index === undefined) {
+			// The list element isn't there, so we need to insert it
+			this.listFrame.children.splice(t,0,this.createListElement(this.list[t]));
+			this.listFrame.children[t].renderInDom(this.listFrame.domNode,this.listFrame.domNode.childNodes[t]);
+		} else {
+			// Delete any list elements preceding the one we want
+			if(index > t) {
+				for(var n=index-1; n>=t; n--) {
+					this.removelistElement(n);
+				}
+			}
+			// Refresh the node we're reusing
+			this.listFrame.children[t].refreshInDom(changes);
+		}
+	}
+	// Remove any left over elements
+	if(this.listFrame.children.length > this.list.length) {
+		for(t=this.listFrame.children.length-1; t>=this.list.length; t--) {
+			this.removeStoryElement(t);
 		}
-		return $tw.Tree.Element("ul",attributes,children);
 	}
 };