Refactor importing of encrypted TiddlyWiki files so that it works on Node.js

core/modules/utils/crypto.js

@@ -0,0 +1,80 @@
+/*\
+title: $:/core/modules/utils/crypto.js
+type: application/javascript
+module-type: utils
+
+Utility functions related to crypto.
+
+\*/
+(function(){
+
+/*jslint node: true, browser: true */
+/*global $tw: false */
+"use strict";
+
+/*
+Look for an encrypted store area in the text of a TiddlyWiki file
+*/
+exports.extractEncryptedStoreArea = function(text) {
+	var encryptedStoreAreaStartMarker = "<pre id=\"encryptedStoreArea\" type=\"text/plain\" style=\"display:none;\">",
+		encryptedStoreAreaStart = text.indexOf(encryptedStoreAreaStartMarker);
+	if(encryptedStoreAreaStart !== -1) {
+		var encryptedStoreAreaEnd = text.indexOf("</pre>",encryptedStoreAreaStart);
+		if(encryptedStoreAreaEnd !== -1) {
+			return $tw.utils.htmlDecode(text.substring(encryptedStoreAreaStart + encryptedStoreAreaStartMarker.length,encryptedStoreAreaEnd-1));
+		}
+	}
+	return null;
+};
+
+/*
+Attempt to extract the tiddlers from an encrypted store area using the current password
+*/
+exports.decryptStoreArea = function(encryptedStoreArea) {
+	var decryptedText = $tw.crypto.decrypt(encryptedStoreArea);
+	if(decryptedText) {
+		var json = JSON.parse(decryptedText),
+			tiddlers = [];
+		for(var title in json) {
+			tiddlers.push(json[title]);
+		}
+		return tiddlers;
+	} else {
+		return null;
+	}
+};
+
+exports.decryptStoreAreaInteractive = function(encryptedStoreArea,callback) {
+	// Try to decrypt with the current password
+	var tiddlers = $tw.utils.decryptStoreArea(encryptedStoreArea);
+	if(tiddlers) {
+		callback(tiddlers);
+	} else {
+		// Prompt for a new password and keep trying
+		$tw.passwordPrompt.createPrompt({
+			serviceName: "Enter a password to decrypt the imported TiddlyWiki",
+			noUserName: true,
+			canCancel: true,
+			submitText: "Decrypt",
+			callback: function(data) {
+				// Exit if the user cancelled
+				if(!data) {
+					return false;
+				}
+				// Attempt to decrypt the tiddlers
+				$tw.crypto.setPassword(data.password);
+				var tiddlers = $tw.utils.decryptStoreArea(encryptedStoreArea);
+				if(tiddlers) {
+					callback(tiddlers);
+					// Exit and remove the password prompt
+					return true;
+				} else {
+					// We didn't decrypt everything, so continue to prompt for password
+					return false;
+				}
+			}
+		});
+	}
+};
+
+})();