Modals: add navigator to handle tm-navigate (#5027)

* Wrap modal in a navigator widget to allow tm-navigate to work

* Move all story list handling to Modal

* Make sure any values for story list or history list sent as variables have precedence

* Code clean up

core/modules/utils/dom/modal.js

@@ -13,6 +13,7 @@ Modal message mechanism
 "use strict";
 
 var widget = require("$:/core/modules/widgets/widget.js");
+var navigator = require("$:/core/modules/widgets/navigator.js");
 
 var Modal = function(wiki) {
 	this.wiki = wiki;
@@ -41,7 +42,12 @@ Modal.prototype.display = function(title,options) {
 		return;
 	}
 	// Create the variables
-	var variables = $tw.utils.extend({currentTiddler: title},options.variables);
+	var variables = $tw.utils.extend({
+			currentTiddler: title,
+			"tv-story-list": (options.event && options.event.widget ? options.event.widget.getVariable("tv-story-list") : ""),
+			"tv-history-list": (options.event && options.event.widget ? options.event.widget.getVariable("tv-history-list") : "")
+		},options.variables);
+
 	// Create the wrapper divs
 	var wrapper = this.srcDocument.createElement("div"),
 		modalBackdrop = this.srcDocument.createElement("div"),
@@ -75,6 +81,31 @@ Modal.prototype.display = function(title,options) {
 	modalFooter.appendChild(modalFooterHelp);
 	modalFooter.appendChild(modalFooterButtons);
 	modalWrapper.appendChild(modalFooter);
+	var navigatorTree = {
+		"type": "navigator",
+		"attributes": {
+			"story": {
+				"name": "story",
+				"type": "string",
+				"value": variables["tv-story-list"]
+			},
+			"history": {
+				"name": "history",
+				"type": "string",
+				"value": variables["tv-history-list"]
+			}
+		},
+		"tag": "$navigator",
+		"isBlock": true,
+		"children": []
+	};
+	var navigatorWidgetNode = new navigator.navigator(navigatorTree, {
+		wiki: this.wiki,
+		document : this.srcDocument,
+		parentWidget: $tw.rootWidget
+	});
+	navigatorWidgetNode.render(modalBody,null);
+	
 	// Render the title of the message
 	var headerWidgetNode = this.wiki.makeTranscludeWidget(title,{
 		field: "subtitle",
@@ -86,7 +117,7 @@ Modal.prototype.display = function(title,options) {
 					type: "string",
 					value: title
 		}}}],
-		parentWidget: $tw.rootWidget,
+		parentWidget: navigatorWidgetNode,
 		document: this.srcDocument,
 		variables: variables,
 		importPageMacros: true
@@ -94,11 +125,12 @@ Modal.prototype.display = function(title,options) {
 	headerWidgetNode.render(headerTitle,null);
 	// Render the body of the message
 	var bodyWidgetNode = this.wiki.makeTranscludeWidget(title,{
-		parentWidget: $tw.rootWidget,
+		parentWidget: navigatorWidgetNode,
 		document: this.srcDocument,
 		variables: variables,
 		importPageMacros: true
 	});
+
 	bodyWidgetNode.render(modalBody,null);
 	// Setup the link if present
 	if(options.downloadLink) {
@@ -135,7 +167,7 @@ Modal.prototype.display = function(title,options) {
 						value: $tw.language.getString("Buttons/Close/Caption")
 			}}}
 		]}],
-		parentWidget: $tw.rootWidget,
+		parentWidget: navigatorWidgetNode,
 		document: this.srcDocument,
 		variables: variables,
 		importPageMacros: true