From 044ec05a1e105b085fee1c5f3a29e6be67a7a651 Mon Sep 17 00:00:00 2001
From: lumos309 <35829443+lumos309@users.noreply.github.com>
Date: Wed, 31 Jul 2019 17:31:30 +0800
Subject: [PATCH 1/2] Resize viewport to fit drawing

---
 public/externalLibs/visualizer/visualizer.js | 83 +++++++++++++++++---
 1 file changed, 74 insertions(+), 9 deletions(-)

diff --git a/public/externalLibs/visualizer/visualizer.js b/public/externalLibs/visualizer/visualizer.js
index df49841db6..c1eacf12a4 100644
--- a/public/externalLibs/visualizer/visualizer.js
+++ b/public/externalLibs/visualizer/visualizer.js
@@ -7,11 +7,6 @@
   container.id = 'list-visualizer-container'
   container.hidden = true
   document.body.appendChild(container)
-  stage = new Kinetic.Stage({
-    width: 1000,
-    height: 1000,
-    container: 'list-visualizer-container'
-  })
 
   /**
    *  Converts a list, or a pair, to a tree object. Wrapper function.
@@ -871,9 +866,14 @@
    *  Then shift it to the left end.
    */
   function draw(xs) {
+    stage = new Kinetic.Stage({
+      width: findListWidth(xs) * 45 + 200,
+      height: findListHeight(xs) * 60 + 100,
+      container: 'list-visualizer-container'
+    });
     minLeft = 500
     nodelist = []
-		fnNodeList = []
+    fnNodeList = []
     nodeLabel = 0
     // hides all other layers
     for (var i = 0; i < layerList.length; i++) {
@@ -951,10 +951,75 @@
     updateListVisualizerButtons()
   }
 	
-	function is_function(data) {
-		return typeof(data) == "function"
-	}
+  function is_function(data) {
+    return typeof(data) == "function"
+  }
+
+  /**
+   * Find the height of a drawing (in number of "rows" of pairs)
+   */ 
+  function findListHeight(xs) {
+    // Store pairs/arrays that were traversed previously so as to not double-count their height.
+    const existing = []; 
+
+     function helper(xs) {   
+      if ((!is_pair(xs) && !is_array(xs)) || is_null(xs)) {
+          return 0;
+      } else {
+        const leftHeight = existing.includes(xs[0])
+                           ? 0
+                           : helper(xs[0]);
+        if (!existing.includes(xs[0]) 
+          && (is_pair(xs[0]) || is_array(xs[0]))) {
+          existing.push(xs[0]);
+        }
+        const rightHeight = existing.includes(xs[1])
+                           ? 0
+                           : helper(xs[1]);
+        if (!existing.includes(xs[1])
+          && (is_pair(xs[1]) || is_array(xs[1]))) {
+          existing.push(xs[1]);
+        }
+        return leftHeight > rightHeight
+              ? 1 + leftHeight
+              : 1 + rightHeight;
+      }
+    }
+
+    return helper(xs, []);
+  }
+
+ /**
+  * Find the width of a drawing (in number of "columns" of pairs)
+  */ 
+  function findListWidth(xs) {
+    const existing = [];
+
+    function helper(xs) {   
+      if ((!is_pair(xs) && !is_array(xs)) || is_null(xs)) {
+          return 0;
+      } else {
+        const leftHeight = existing.includes(xs[0])
+                           ? 0
+                           : helper(xs[0]);
+        if (!existing.includes(xs[0]) 
+          && (is_pair(xs[0]) || is_array(xs[0]))) {
+          existing.push(xs[0]);
+        }
+        const rightHeight = existing.includes(xs[1])
+                           ? 0
+                           : helper(xs[1]);
+        if (!existing.includes(xs[1])
+          && (is_pair(xs[1]) || is_array(xs[1]))) {
+          existing.push(xs[1]);
+        }
+        return leftHeight + rightHeight + 1;
+      }
+    }
 
+    return helper(xs);
+  }
+	
   exports.ListVisualizer = {
     draw: draw,
     clear: clearListVisualizer,

From 8a4377430cec983ae4e9b33727fc1027c1a33b69 Mon Sep 17 00:00:00 2001
From: lumos309 <35829443+lumos309@users.noreply.github.com>
Date: Sun, 4 Aug 2019 17:04:43 +0800
Subject: [PATCH 2/2] Fixed bug for circular lists

---
 public/externalLibs/visualizer/visualizer.js | 46 +++++++++++---------
 1 file changed, 25 insertions(+), 21 deletions(-)

diff --git a/public/externalLibs/visualizer/visualizer.js b/public/externalLibs/visualizer/visualizer.js
index c1eacf12a4..8bfd902742 100644
--- a/public/externalLibs/visualizer/visualizer.js
+++ b/public/externalLibs/visualizer/visualizer.js
@@ -966,19 +966,21 @@
       if ((!is_pair(xs) && !is_array(xs)) || is_null(xs)) {
           return 0;
       } else {
-        const leftHeight = existing.includes(xs[0])
-                           ? 0
-                           : helper(xs[0]);
-        if (!existing.includes(xs[0]) 
-          && (is_pair(xs[0]) || is_array(xs[0]))) {
+        let leftHeight;
+        let rightHeight;
+        if (existing.includes(xs[0])
+            || (!is_pair(xs[0]) && (!is_array(xs[0])))) {
+          leftHeight = 0;          
+        } else {
           existing.push(xs[0]);
+          leftHeight = helper(xs[0]);
         }
-        const rightHeight = existing.includes(xs[1])
-                           ? 0
-                           : helper(xs[1]);
-        if (!existing.includes(xs[1])
-          && (is_pair(xs[1]) || is_array(xs[1]))) {
+        if (existing.includes(xs[1])
+            || (!is_pair(xs[1]) && (!is_array(xs[1])))) {
+          rightHeight = 0;          
+        } else {
           existing.push(xs[1]);
+          rightHeight = helper(xs[1]);
         }
         return leftHeight > rightHeight
               ? 1 + leftHeight
@@ -999,21 +1001,23 @@
       if ((!is_pair(xs) && !is_array(xs)) || is_null(xs)) {
           return 0;
       } else {
-        const leftHeight = existing.includes(xs[0])
-                           ? 0
-                           : helper(xs[0]);
-        if (!existing.includes(xs[0]) 
-          && (is_pair(xs[0]) || is_array(xs[0]))) {
+        let leftWidth;
+        let rightWidth;
+        if (existing.includes(xs[0])
+            || (!is_pair(xs[0]) && (!is_array(xs[0])))) {
+          leftWidth = 0;          
+        } else {
           existing.push(xs[0]);
+          leftWidth = helper(xs[0]);
         }
-        const rightHeight = existing.includes(xs[1])
-                           ? 0
-                           : helper(xs[1]);
-        if (!existing.includes(xs[1])
-          && (is_pair(xs[1]) || is_array(xs[1]))) {
+        if (existing.includes(xs[1])
+            || (!is_pair(xs[1]) && (!is_array(xs[1])))) {
+          rightWidth = 0;          
+        } else {
           existing.push(xs[1]);
+          rightWidth = helper(xs[1]);
         }
-        return leftHeight + rightHeight + 1;
+        return leftWidth + rightWidth + 1;
       }
     }