From 390b2373e9efae553d2337ad1d356e7ca626b7fb Mon Sep 17 00:00:00 2001
From: Ray Schamp <ray@scratch.mit.edu>
Date: Wed, 15 Feb 2017 19:16:37 -0500
Subject: [PATCH] Refactor filter methods into util

---
 src/util/filter-toolbox.js | 49 ++++++++++++++++++++++++++++++++++++++
 src/virtual-machine.js     | 29 ++++++++++------------
 2 files changed, 61 insertions(+), 17 deletions(-)
 create mode 100644 src/util/filter-toolbox.js

diff --git a/src/util/filter-toolbox.js b/src/util/filter-toolbox.js
new file mode 100644
index 000000000..c4b18b41c
--- /dev/null
+++ b/src/util/filter-toolbox.js
@@ -0,0 +1,49 @@
+/**
+ * Filter Blockly toolbox XML node containing blocks to only those with
+ * valid opcodes. Return a copy of the node with valid blocks.
+ * @param {HTMLElement} node Blockly toolbox XML node
+ * @param {Array.<string>} opcodes Valid opcodes. Blocks producing other opcodes
+ * will be filtered.
+ * @returns {HTMLElement} filtered toolbox XML node
+ */
+var filterToolboxNode = function (node, opcodes) {
+    var filteredCategory = node.cloneNode();
+    for (var block = node.firstElementChild; block; block = block.nextElementSibling) {
+        if (block.nodeName.toLowerCase() !== 'block') continue;
+        var opcode = block.getAttribute('type').toLowerCase();
+        if (opcodes.indexOf(opcode) !== -1) {
+            filteredCategory.appendChild(block.cloneNode(true));
+        }
+    }
+    return filteredCategory;
+};
+
+/**
+ * Filter Blockly toolbox XML and return a copy which only contains blocks with
+ * existent opcodes. Categories with no valid children will be removed.
+ * @param {HTMLElement} toolbox Blockly toolbox XML node
+ * @param {Array.<string>} opcodes Valid opcodes. Blocks producing other opcodes
+ * will be filtered.
+ * @returns {HTMLElement} filtered toolbox XML node
+ */
+var filterToolbox = function (toolbox, opcodes) {
+    if (!toolbox.hasChildNodes()) return toolbox;
+    var filteredToolbox;
+    if (toolbox.firstElementChild.nodeName.toLowerCase() === 'category') {
+        filteredToolbox = toolbox.cloneNode();
+        for (
+            var category = toolbox.firstElementChild;
+            category;
+            category = category.nextElementSibling
+        ) {
+            if (category.nodeName.toLowerCase() !== 'category') continue;
+            var filteredCategory = filterToolboxNode(category, opcodes);
+            if (filteredCategory.hasChildNodes()) filteredToolbox.appendChild(filteredCategory);
+        }
+    } else {
+        filteredToolbox = filterToolboxNode(toolbox, opcodes);
+    }
+    return filteredToolbox;
+};
+
+module.exports = filterToolbox;
diff --git a/src/virtual-machine.js b/src/virtual-machine.js
index 52616e7c2..1f3bdfa1f 100644
--- a/src/virtual-machine.js
+++ b/src/virtual-machine.js
@@ -1,6 +1,7 @@
 var EventEmitter = require('events');
 var util = require('util');
 
+var filterToolbox = require('./util/filter-toolbox');
 var Runtime = require('./engine/runtime');
 var sb2import = require('./import/sb2import');
 
@@ -336,23 +337,17 @@ VirtualMachine.prototype.postSpriteInfo = function (data) {
     this.editingTarget.postSpriteInfo(data);
 };
 
-VirtualMachine.prototype.filterToolbox = function (toolboxDOM) {
-    var filteredToolbox = toolboxDOM.cloneNode();
-    var category = toolboxDOM.firstElementChild;
-    while (category) {
-        var filteredCategory = category.cloneNode();
-        var block = category.firstElementChild;
-        while (block) {
-            var opcode = block.getAttribute('type');
-            if (opcode in this.runtime._primitives || opcode in this.runtime._hats) {
-                filteredCategory.appendChild(block.cloneNode(true));
-            }
-            block = block.nextElementSibling;
-        }
-        if (filteredCategory.hasChildNodes()) filteredToolbox.appendChild(filteredCategory);
-        category = category.nextElementSibling;
-    }
-    return filteredToolbox;
+
+/**
+ * Filter Blockly toolbox XML and return a copy which only contains blocks with
+ * existent opcodes. Categories with no valid children will be removed.
+ * @param {HTMLElement} toolbox Blockly toolbox XML node
+ * @returns {HTMLElement} filtered toolbox XML node
+ */
+VirtualMachine.prototype.filterToolbox = function (toolbox) {
+    var opcodes = Object.keys(this.runtime._primitives)
+        .concat(Object.keys(this.runtime._hats));
+    return filterToolbox(toolbox, opcodes);
 };
 
 module.exports = VirtualMachine;