add BitcoinAddress

BitcoinAddress.js

@@ -0,0 +1,99 @@
+require('classtool');
+
+function ClassSpec(b) {
+	var base58 = b.base58 || require('base58-native').base58Check;
+
+	function BitcoinAddress(data, encoding) {
+    this.data = data;
+    this.__proto__ = encodings[encoding || 'base58'];
+	};
+
+  // return the bitcoin address version (the first byte of the address)
+  BitcoinAddress.prototype.version = function() {
+    return this.as('binary').readUInt8(0);
+  };
+
+  // get or set the encoding used (transforms data)
+  BitcoinAddress.prototype.encoding = function(encoding) {
+    if(encoding) {
+      this.data = this.as(encoding);
+      this.__proto__ = encodings[encoding];
+    }
+    return this._encoding;
+  };
+
+  // answer a new instance having the given encoding
+  BitcoinAddress.prototype.withEncoding = function(encoding) {
+    return new BitcoinAddress(this.as(encoding), encoding);
+  };
+
+  // answer the data in the given encoding
+  BitcoinAddress.prototype.as = function(encoding) {
+    if(!encodings[encoding]) throw new Error('invalid encoding');
+    return this.converters[encoding].call(this);
+  };
+
+  // validate the address (basically just check that we have 21 bytes)
+  BitcoinAddress.prototype.validate = function() {
+    this.withEncoding('binary').validate();
+  };
+
+  // convert to a string (in base58 form)
+	BitcoinAddress.prototype.toString = function() {
+    return this.as('base58');
+	};
+
+  // Setup support for various address encodings.  The object for
+  // each encoding inherits from the BitcoinAddress prototype.  This
+  // allows any encoding to override any method...changing the encoding
+  // for an instance will change the encoding it inherits from.  Note,
+  // this will present some problems for anyone wanting to inherit from
+  // BitcoinAddress (we'll deal with that when needed).
+  var encodings = {
+    'binary': {
+      converters: {
+        'base58': function() {
+          return base58.encode(this.data);
+        },
+        'hex': function() {
+          return this.data.toString('hex');
+        },
+      },
+
+      validate: function() {
+        if(this.data.length != 21) throw new Error('invalid data length');
+      },
+    },
+
+    'base58': {
+      converters: {
+        'binary': function() {
+          return base58.decode(this.data);
+        },
+        'hex': function() {
+          return this.withEncoding('binary').as('hex');
+        },
+      },
+    },
+
+    'hex': {
+      converters: {
+        'binary': function() {
+          return new Buffer(this.data, 'hex');
+        },
+        'base58': function() {
+          return this.withEncoding('binary').as('base58');
+        },
+      },
+    },
+  };
+
+  for(var k in encodings) {
+    encodings[k].converters[k] = function() {return this.data;};
+    encodings[k]._encoding = k;
+    encodings[k].__proto__ = BitcoinAddress.prototype;
+  };
+  
+	return BitcoinAddress;
+};
+module.defineClass(ClassSpec);

package.json

@@ -1,7 +1,7 @@
 {
   "name": "libcoin",
   "description": "Bitcoin Library",
-  "version": "0.1.0",
+  "version": "0.1.1",
   "author": {
     "name": "Stephen Pair",
     "email": "stephen@bitpay.com"
@@ -20,6 +20,10 @@
     "url": "http://github.com/gasteve/node-libcoin.git"
   },
   "scripts": {},
+  "dependencies": {
+    "classtool": ">=1.0.0",
+    "base58-native": ">=0.1.1"
+  },
   "devDependencies": {},
   "license": "MIT"
 }