Add experimental CodeMirror plugin

The plugin is incomplete, and currently abandoned. It loads up an
instance of CodeMirror as an editor, and loads the right tiddler into
it, but the work hasn't been done to allow changes to be saved. The
startup time is ridiculously long, which is why I abandoned it.

plugins/tiddlywiki/codemirror/codemirroreditor.js

@@ -0,0 +1,108 @@
+/*\
+title: $:/plugins/tiddlywiki/codemirror/codemirroreditor.js
+type: application/javascript
+module-type: editor
+
+A Codemirror text editor
+
+\*/
+(function(){
+
+/*jslint node: true, browser: true */
+/*global $tw: false */
+"use strict";
+
+if($tw.browser) {
+	require("./codemirror.js")
+}
+
+var CodeMirrorEditor = function(editWidget,tiddlerTitle,fieldName) {
+	this.editWidget = editWidget;
+	this.tiddlerTitle = tiddlerTitle;
+	this.fieldName = fieldName;
+};
+
+/*
+Get the tiddler being edited and current value
+*/
+CodeMirrorEditor.prototype.getEditInfo = function() {
+	// Get the current tiddler and the field name
+	var tiddler = this.editWidget.renderer.renderTree.wiki.getTiddler(this.tiddlerTitle),
+		value;
+	// If we've got a tiddler, the value to display is the field string value
+	if(tiddler) {
+		value = tiddler.getFieldString(this.fieldName);
+	} else {
+		// Otherwise, we need to construct a default value for the editor
+		switch(this.fieldName) {
+			case "text":
+				value = "Type the text for the tiddler '" + this.tiddlerTitle + "'";
+				break;
+			case "title":
+				value = this.tiddlerTitle;
+				break;
+			default:
+				value = "";
+				break;
+		}
+		value = this.editWidget.renderer.getAttribute("default",value);
+	}
+	return {tiddler: tiddler, value: value};
+};
+
+CodeMirrorEditor.prototype.render = function() {
+	// Get the initial value of the editor
+	var editInfo = this.getEditInfo();
+	// Create the editor nodes
+	var node = {
+		type: "element",
+		attributes: {}
+	};
+	this.type = this.editWidget.renderer.getAttribute("type",this.fieldName === "text" ? "textarea" : "input");
+	switch(this.type) {
+		case "textarea":
+			node.tag = "textarea";
+			node.children = [{
+				type: "text",
+				text: editInfo.value
+			}];
+			break;
+		case "search":
+			node.tag = "input";
+			node.attributes.type = {type: "string", value: "search"};
+			node.attributes.value = {type: "string", value: editInfo.value};
+			break;
+		default: // "input"
+			node.tag = "input";
+			node.attributes.type = {type: "string", value: "text"};
+			node.attributes.value = {type: "string", value: editInfo.value};
+			break;
+	}
+	// Set the element details
+	this.editWidget.tag = this.editWidget.renderer.parseTreeNode.isBlock ? "div" : "span";
+	this.editWidget.attributes = {
+		"class": "tw-edit-CodeMirrorEditor"
+	};
+	this.editWidget.children = this.editWidget.renderer.renderTree.createRenderers(this.editWidget.renderer.renderContext,[node]);
+};
+
+CodeMirrorEditor.prototype.postRenderInDom = function() {
+	if(this.type === "textarea") {
+		CodeMirror.fromTextArea(this.editWidget.children[0].domNode,{
+			lineWrapping: true,
+			lineNumbers: true
+		});
+	}
+};
+
+CodeMirrorEditor.prototype.refreshInDom = function() {
+	if(document.activeElement !== this.editWidget.children[0].domNode) {
+		var editInfo = this.getEditInfo();
+		this.editWidget.children[0].domNode.value = editInfo.value;
+	}
+};
+
+exports["text/vnd.tiddlywiki"] = CodeMirrorEditor;
+exports["text/plain"] = CodeMirrorEditor;
+
+})();