From bab9fec836e9ccebb2cb1f3a8ffe627fdd1dfa22 Mon Sep 17 00:00:00 2001
From: wltsmrz <wltsmrz@gmail.com>
Date: Thu, 12 Sep 2013 14:17:51 -0700
Subject: [PATCH] Refactor currency parsing

---
 src/js/ripple/currency.js | 42 ++++++++++++++++++++++-----------------
 1 file changed, 24 insertions(+), 18 deletions(-)

diff --git a/src/js/ripple/currency.js b/src/js/ripple/currency.js
index 64bfbcfc..eef1f042 100644
--- a/src/js/ripple/currency.js
+++ b/src/js/ripple/currency.js
@@ -51,26 +51,32 @@ Currency.prototype.equals = function (d) {
 
 // this._value = NaN on error.
 Currency.prototype.parse_json = function (j) {
-  if (j instanceof Currency) {
-    j.copyTo(this);
-  } else if (typeof j === 'string') {
-    if (j === "" || j === "0" || j === "XRP") {
-      // XRP is never allowed as a Currency object
-      this._value = 0;
-    } else if (j.length === 3) {
-      this._value = j;
-    } else {
-      this._value = NaN;
-    }
-  } else if (typeof j === 'number' && !isNaN(j)) {
-    // XXX This is a hack
-    this._value = j;
-  } else if (typeof j !== 'string'|| j.length !== 3) {
-    this._value = NaN;
-  } else {
-    this._value = j;
+  var result = NaN;
+
+  switch (typeof j) {
+    case 'string':
+      if (!j || /^(0|XRP)$/.test(j)) {
+        result = 0;
+      } else if (/^[a-zA-Z0-9]{3}$/.test(j)) {
+        result = j;
+      }
+      break;
+
+    case 'number':
+      if (!isNaN(j)) {
+        result = j;
+      }
+      break;
+
+    case 'object':
+      if (j instanceof Currency) {
+        result = j.copyTo({})._value;
+      }
+      break;
   }
 
+  this._value = result;
+
   return this;
 };