1 files changed, 156 insertions, 0 deletions
diff --git a/lib/formatters.js b/lib/formatters.js
new file mode 100644
index 000000000..54475ef9c
--- /dev/null
+++ b/lib/formatters.js
@@ -0,0 +1,156 @@
+/*
+    This file is part of ethereum.js.
+
+    ethereum.js is free software: you can redistribute it and/or modify
+    it under the terms of the GNU Lesser General Public License as published by
+    the Free Software Foundation, either version 3 of the License, or
+    (at your option) any later version.
+
+    ethereum.js is distributed in the hope that it will be useful,
+    but WITHOUT ANY WARRANTY; without even the implied warranty of
+    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+    GNU Lesser General Public License for more details.
+
+    You should have received a copy of the GNU Lesser General Public License
+    along with ethereum.js.  If not, see <http://www.gnu.org/licenses/>.
+*/
+/** @file formatters.js
+ * @authors:
+ *   Marek Kotewicz <marek@ethdev.com>
+ * @date 2015
+ */
+
+if (process.env.NODE_ENV !== 'build') {
+    var BigNumber = require('bignumber.js'); // jshint ignore:line
+}
+
+var web3 = require('./web3'); 
+
+BigNumber.config({ ROUNDING_MODE: BigNumber.ROUND_DOWN });
+
+var ETH_PADDING = 32;
+
+/// @param string string to be padded
+/// @param number of characters that result string should have
+/// @param sign, by default 0
+/// @returns right aligned string
+var padLeft = function (string, chars, sign) {
+    return new Array(chars - string.length + 1).join(sign ? sign : "0") + string;
+};
+
+/// Formats input value to byte representation of int
+/// If value is negative, return it's two's complement
+/// If the value is floating point, round it down
+/// @returns right-aligned byte representation of int
+var formatInputInt = function (value) {
+    var padding = ETH_PADDING * 2;
+    if (value instanceof BigNumber || typeof value === 'number') {
+        if (typeof value === 'number')
+            value = new BigNumber(value);
+        value = value.round();
+
+        if (value.lessThan(0)) 
+            value = new BigNumber("ffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff", 16).plus(value).plus(1);
+        value = value.toString(16);
+    }
+    else if (value.indexOf('0x') === 0)
+        value = value.substr(2);
+    else if (typeof value === 'string')
+        value = formatInputInt(new BigNumber(value));
+    else
+        value = (+value).toString(16);
+    return padLeft(value, padding);
+};
+
+/// Formats input value to byte representation of string
+/// @returns left-algined byte representation of string
+var formatInputString = function (value) {
+    return web3.fromAscii(value, ETH_PADDING).substr(2);
+};
+
+/// Formats input value to byte representation of bool
+/// @returns right-aligned byte representation bool
+var formatInputBool = function (value) {
+    return '000000000000000000000000000000000000000000000000000000000000000' + (value ?  '1' : '0');
+};
+
+/// Formats input value to byte representation of real
+/// Values are multiplied by 2^m and encoded as integers
+/// @returns byte representation of real
+var formatInputReal = function (value) {
+    return formatInputInt(new BigNumber(value).times(new BigNumber(2).pow(128))); 
+};
+
+
+/// Check if input value is negative
+/// @param value is hex format
+/// @returns true if it is negative, otherwise false
+var signedIsNegative = function (value) {
+    return (new BigNumber(value.substr(0, 1), 16).toString(2).substr(0, 1)) === '1';
+};
+
+/// Formats input right-aligned input bytes to int
+/// @returns right-aligned input bytes formatted to int
+var formatOutputInt = function (value) {
+    value = value || "0";
+    // check if it's negative number
+    // it it is, return two's complement
+    if (signedIsNegative(value)) {
+        return new BigNumber(value, 16).minus(new BigNumber('ffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff', 16)).minus(1);
+    }
+    return new BigNumber(value, 16);
+};
+
+/// Formats big right-aligned input bytes to uint
+/// @returns right-aligned input bytes formatted to uint
+var formatOutputUInt = function (value) {
+    value = value || "0";
+    return new BigNumber(value, 16);
+};
+
+/// @returns input bytes formatted to real
+var formatOutputReal = function (value) {
+    return formatOutputInt(value).dividedBy(new BigNumber(2).pow(128)); 
+};
+
+/// @returns input bytes formatted to ureal
+var formatOutputUReal = function (value) {
+    return formatOutputUInt(value).dividedBy(new BigNumber(2).pow(128)); 
+};
+
+/// @returns right-aligned input bytes formatted to hex
+var formatOutputHash = function (value) {
+    return "0x" + value;
+};
+
+/// @returns right-aligned input bytes formatted to bool
+var formatOutputBool = function (value) {
+    return value === '0000000000000000000000000000000000000000000000000000000000000001' ? true : false;
+};
+
+/// @returns left-aligned input bytes formatted to ascii string
+var formatOutputString = function (value) {
+    return web3.toAscii(value);
+};
+
+/// @returns right-aligned input bytes formatted to address
+var formatOutputAddress = function (value) {
+    return "0x" + value.slice(value.length - 40, value.length);
+};
+
+
+module.exports = {
+    formatInputInt: formatInputInt,
+    formatInputString: formatInputString,
+    formatInputBool: formatInputBool,
+    formatInputReal: formatInputReal,
+    formatOutputInt: formatOutputInt,
+    formatOutputUInt: formatOutputUInt,
+    formatOutputReal: formatOutputReal,
+    formatOutputUReal: formatOutputUReal,
+    formatOutputHash: formatOutputHash,
+    formatOutputBool: formatOutputBool,
+    formatOutputString: formatOutputString,
+    formatOutputAddress: formatOutputAddress
+};
+