From 538d12e017a03bb44eb638b9008e849562997116 Mon Sep 17 00:00:00 2001
From: Jeremy Ruston <jeremy@osmosoft.com>
Date: Sun, 2 Jun 2013 23:20:43 +0100
Subject: [PATCH] Add the fieldlist widget

Allows us to render a sequence of fields
---
 core/modules/widgets/fieldlist.js | 150 ++++++++++++++++++++++++++++++
 1 file changed, 150 insertions(+)
 create mode 100644 core/modules/widgets/fieldlist.js

diff --git a/core/modules/widgets/fieldlist.js b/core/modules/widgets/fieldlist.js
new file mode 100644
index 000000000..eea73abec
--- /dev/null
+++ b/core/modules/widgets/fieldlist.js
@@ -0,0 +1,150 @@
+/*\
+title: $:/core/modules/widgets/fieldlist.js
+type: application/javascript
+module-type: widget
+
+The fieldlist widget renders the fields of a tiddler through a template.
+
+\*/
+(function(){
+
+/*jslint node: true, browser: true */
+/*global $tw: false */
+"use strict";
+
+var FieldListWidget = function(renderer) {
+	// Save state
+	this.renderer = renderer;
+	// Generate child nodes
+	this.generate();
+};
+
+FieldListWidget.prototype.generate = function() {
+	var self = this;
+	// Get parameters from our attributes
+	this.tiddlerTitle = this.renderer.getAttribute("tiddler",this.renderer.tiddlerTitle);
+	this.exclude = this.renderer.getAttribute("exclude");
+	// Get the exclusion list
+	this.excludeList;
+	if(this.exclude) {
+		this.excludeList = this.exclude.split(" ");
+	} else {
+		this.excludeList = ["text"]; 
+	}
+	// Get the list of fields
+	var fieldList = this.getFieldList();
+	// Set the element
+	this.tag = "div";
+	this.attributes = {
+		"class": "tw-fields"
+	};
+	// Set up the attributes for the wrapper element
+	var classes = [];
+	if(this.renderer.hasAttribute("class")) {
+		$tw.utils.pushTop(classes,this.renderer.getAttribute("class").split(" "));
+	}
+	if(classes.length > 0) {
+		this.attributes["class"] = classes.join(" ");
+	}
+	if(this.renderer.hasAttribute("style")) {
+		this.attributes.style = this.renderer.getAttribute("style");
+	}
+	if(this.renderer.hasAttribute("tooltip")) {
+		this.attributes.title = this.renderer.getAttribute("tooltip");
+	}
+	// Create the renderers for each list item
+	var items = [];
+	$tw.utils.each(fieldList,function(fieldName) {
+		items.push(self.createListElement(fieldName));
+	});
+	this.children = this.renderer.renderTree.createRenderers(this.renderer,items);
+};
+
+FieldListWidget.prototype.createListElement = function(fieldName) {
+	return {
+		type: "element",
+		tag: "$transclude",
+		isBlock: true,
+		attributes: {
+			currentField: {type: "string", value: fieldName},
+			target: {type: "string", value: this.tiddlerTitle}
+		},
+		children: this.renderer.parseTreeNode.children
+	};
+};
+
+FieldListWidget.prototype.removeListElement = function(index) {
+	// Get the list element
+	var listElement = this.children[index];
+	// Delete the DOM node
+	listElement.domNode.parentNode.removeChild(listElement.domNode);
+	// Then delete the actual renderer node
+	this.children.splice(index,1);
+};
+
+FieldListWidget.prototype.getFieldList = function() {
+	var tiddler = this.renderer.renderTree.wiki.getTiddler(this.tiddlerTitle),
+		fieldList = [];
+	if(tiddler) {
+		for(var fieldName in tiddler.fields) {
+			if(this.excludeList.indexOf(fieldName) === -1) {
+				fieldList.push(fieldName);
+			}
+		}
+	}
+	fieldList.sort();
+	return fieldList;
+};
+
+FieldListWidget.prototype.refreshInDom = function(changedAttributes,changedTiddlers) {
+	// Check if any of our attributes have changed, or if a tiddler we're interested in has changed
+	if(changedAttributes.tiddler || changedAttributes.exclude || changedAttributes.style || changedAttributes.tooltip || changedAttributes["class"]) {
+		// Regenerate and rerender the widget and replace the existing DOM node
+		this.generate();
+		var oldDomNode = this.renderer.domNode,
+			newDomNode = this.renderer.renderInDom();
+		oldDomNode.parentNode.replaceChild(newDomNode,oldDomNode);
+	} else {
+		// Get the potentially updated list of fields
+		var fieldList = this.getFieldList();
+		// Walk through the fields
+		for(var fieldIndex = 0; fieldIndex<fieldList.length; fieldIndex++) {
+			// Look for the field in the rendered child nodes
+			var targetIndex = this.findChildNode(fieldIndex,fieldList[fieldIndex]);
+			if(targetIndex === -1) {
+				// Insert the field if it wasn't present
+				this.children.splice(fieldIndex,0,this.renderer.renderTree.createRenderer(this.renderer,this.createListElement(fieldList[fieldIndex])));
+				this.renderer.domNode.insertBefore(this.children[fieldIndex].renderInDom(),this.renderer.domNode.childNodes[fieldIndex]);
+			} else {
+				// Delete any list elements preceding the one we want
+				for(var n=targetIndex-1; n>=fieldIndex; n--) {
+					this.removeListElement(n);
+				}
+				// Refresh the node we're reusing
+				this.children[fieldIndex].refreshInDom(changedTiddlers);
+			}
+		}
+		// Remove any left over elements
+		for(fieldIndex = this.children.length-1; fieldIndex>=fieldList.length; fieldIndex--) {
+			this.removeListElement(fieldIndex);
+		}
+	}
+};
+
+/*
+Find the index of the child node representing the named field (or -1 if not present)
+*/
+FieldListWidget.prototype.findChildNode = function(startIndex,fieldName) {
+	var index = startIndex;
+	while(index < this.children.length) {
+		if(this.children[index].attributes.currentField === fieldName) {
+			return index;
+		}
+		index++;
+	}
+	return -1;
+};
+
+exports.fieldlist = FieldListWidget;
+
+})();