Add gh-pages script

Author: ArthurClemens

demo/index.html

@@ -56,7 +56,7 @@
       </div>
     </div>
 
-    <script type="text/javascript" src="../lib/undomanager.js"></script>
+    <script type="text/javascript" src="js/undomanager.js"></script>
     <script type="text/javascript" src="js/demo.js"></script>
     <script type="text/javascript" src="js/circledrawer.js"></script>
   </body>

demo/js/undomanager.js

@@ -0,0 +1,158 @@
+/*
+Simple JavaScript undo and redo.
+https://github.com/ArthurClemens/JavaScript-Undo-Manager
+*/
+
+(function () {
+  'use strict';
+
+  function removeFromTo(array, from, to) {
+    array.splice(
+      from,
+      !to ||
+        1 +
+          to -
+          from +
+          (!((to < 0) ^ (from >= 0)) && (to < 0 || -1) * array.length),
+    );
+    return array.length;
+  }
+
+  let UndoManager = function () {
+    let commands = [],
+      index = -1,
+      limit = 0,
+      isExecuting = false,
+      callback,
+      // functions
+      execute;
+
+    execute = function (command, action) {
+      if (!command || typeof command[action] !== 'function') {
+        return this;
+      }
+      isExecuting = true;
+
+      command[action]();
+
+      isExecuting = false;
+      return this;
+    };
+
+    return {
+      /*
+      Add a command to the queue.
+      */
+      add: function (command) {
+        if (isExecuting) {
+          return this;
+        }
+        // if we are here after having called undo,
+        // invalidate items higher on the stack
+        commands.splice(index + 1, commands.length - index);
+
+        commands.push(command);
+
+        // if limit is set, remove items from the start
+        if (limit && commands.length > limit) {
+          removeFromTo(commands, 0, -(limit + 1));
+        }
+
+        // set the current index to the end
+        index = commands.length - 1;
+        if (callback) {
+          callback();
+        }
+        return this;
+      },
+
+      /*
+      Pass a function to be called on undo and redo actions.
+      */
+      setCallback: function (callbackFunc) {
+        callback = callbackFunc;
+      },
+
+      /*
+      Perform undo: call the undo function at the current index and decrease the index by 1.
+      */
+      undo: function () {
+        let command = commands[index];
+        if (!command) {
+          return this;
+        }
+        execute(command, 'undo');
+        index -= 1;
+        if (callback) {
+          callback();
+        }
+        return this;
+      },
+
+      /*
+      Perform redo: call the redo function at the next index and increase the index by 1.
+      */
+      redo: function () {
+        let command = commands[index + 1];
+        if (!command) {
+          return this;
+        }
+        execute(command, 'redo');
+        index += 1;
+        if (callback) {
+          callback();
+        }
+        return this;
+      },
+
+      /*
+      Clear the memory, losing all stored states. Reset the index.
+      */
+      clear: function () {
+        let prev_size = commands.length;
+
+        commands = [];
+        index = -1;
+
+        if (callback && prev_size > 0) {
+          callback();
+        }
+      },
+
+      hasUndo: function () {
+        return index !== -1;
+      },
+
+      hasRedo: function () {
+        return index < commands.length - 1;
+      },
+
+      getCommands: function () {
+        return commands;
+      },
+
+      getIndex: function () {
+        return index;
+      },
+
+      setLimit: function (l) {
+        limit = l;
+      },
+    };
+  };
+
+  if (
+    typeof define === 'function' &&
+    typeof define.amd === 'object' &&
+    define.amd
+  ) {
+    // AMD. Register as an anonymous module.
+    define(function () {
+      return UndoManager;
+    });
+  } else if (typeof module !== 'undefined' && module.exports) {
+    module.exports = UndoManager;
+  } else {
+    window.UndoManager = UndoManager;
+  }
+})();

package.json

@@ -8,7 +8,8 @@
   },
   "scripts": {
     "lint": "eslint --ext .js --fix .",
-    "test": "jasmine-browser-runner runSpecs"
+    "test": "jasmine-browser-runner runSpecs",
+    "github": "cp -f ./lib/undomanager.js ./demo/js/ && cp -R demo/* ../gh-pages"
   },
   "devDependencies": {
     "chromedriver": "^110.0.0",