Files
rippled/src/js/amount.js

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25 KiB
JavaScript

// Represent Ripple amounts and currencies.
// - Numbers in hex are big-endian.
var sjcl = require('../../build/sjcl');
var bn = sjcl.bn;
var utils = require('./utils');
var jsbn = require('./jsbn');
var BigInteger = jsbn.BigInteger;
var UInt160 = require('./uint160').UInt160,
Seed = require('./seed').Seed,
Currency = require('./currency').Currency;
var consts = exports.consts = {
'currency_xns' : 0,
'currency_one' : 1,
'xns_precision' : 6,
// BigInteger values prefixed with bi_.
'bi_5' : new BigInteger('5'),
'bi_7' : new BigInteger('7'),
'bi_10' : new BigInteger('10'),
'bi_1e14' : new BigInteger(String(1e14)),
'bi_1e16' : new BigInteger(String(1e16)),
'bi_1e17' : new BigInteger(String(1e17)),
'bi_1e32' : new BigInteger('100000000000000000000000000000000'),
'bi_man_max_value' : new BigInteger('9999999999999999'),
'bi_man_min_value' : new BigInteger('1000000000000000'),
'bi_xns_max' : new BigInteger("9000000000000000000"), // Json wire limit.
'bi_xns_min' : new BigInteger("-9000000000000000000"), // Json wire limit.
'bi_xns_unit' : new BigInteger('1000000'),
'cMinOffset' : -96,
'cMaxOffset' : 80,
};
//
// Amount class in the style of Java's BigInteger class
// http://docs.oracle.com/javase/1.3/docs/api/java/math/BigInteger.html
//
var Amount = function () {
// Json format:
// integer : XRP
// { 'value' : ..., 'currency' : ..., 'issuer' : ...}
this._value = new BigInteger(); // NaN for bad value. Always positive for non-XRP.
this._offset = 0; // Always 0 for XRP.
this._is_native = true; // Default to XRP. Only valid if value is not NaN.
this._is_negative = false;
this._currency = new Currency();
this._issuer = new UInt160();
};
// Given "100/USD/mtgox" return the a string with mtgox remapped.
Amount.text_full_rewrite = function (j) {
return Amount.from_json(j).to_text_full();
}
// Given "100/USD/mtgox" return the json.
Amount.json_rewrite = function (j) {
return Amount.from_json(j).to_json();
};
Amount.from_json = function (j) {
return (new Amount()).parse_json(j);
};
Amount.from_human = function (j) {
return (new Amount()).parse_human(j);
};
Amount.is_valid = function (j) {
return Amount.from_json(j).is_valid();
};
Amount.is_valid_full = function (j) {
return Amount.from_json(j).is_valid_full();
};
Amount.NaN = function () {
var result = new Amount();
result._value = NaN;
return result;
};
// Returns a new value which is the absolute value of this.
Amount.prototype.abs = function () {
return this.clone(this.is_negative());
};
// Result in terms of this' currency and issuer.
Amount.prototype.add = function (v) {
var result;
if (!this.is_comparable(v)) {
result = Amount.NaN();
}
else if (this._is_native) {
result = new Amount();
var v1 = this._is_negative ? this._value.negate() : this._value;
var v2 = v._is_negative ? v._value.negate() : v._value;
var s = v1.add(v2);
result._is_negative = s.compareTo(BigInteger.ZERO) < 0;
result._value = result._is_negative ? s.negate() : s;
}
else if (v.is_zero()) {
result = this;
}
else if (this.is_zero()) {
result = v.clone();
// YYY Why are these cloned? We never modify them.
result._currency = this._currency.clone();
result._issuer = this._issuer.clone();
}
else
{
var v1 = this._is_negative ? this._value.negate() : this._value;
var o1 = this._offset;
var v2 = v._is_negative ? v._value.negate() : v._value;
var o2 = v._offset;
while (o1 < o2) {
v1 = v1.divide(consts.bi_10);
o1 += 1;
}
while (o2 < o1) {
v2 = v2.divide(consts.bi_10);
o2 += 1;
}
result = new Amount();
result._is_native = false;
result._offset = o1;
result._value = v1.add(v2);
result._is_negative = result._value.compareTo(BigInteger.ZERO) < 0;
if (result._is_negative) {
result._value = result._value.negate();
}
result._currency = this._currency.clone();
result._issuer = this._issuer.clone();
result.canonicalize();
}
return result;
};
Amount.prototype.canonicalize = function () {
if (!(this._value instanceof BigInteger))
{
// NaN.
// nothing
}
else if (this._is_native) {
// Native.
if (this._value.equals(BigInteger.ZERO)) {
this._offset = 0;
this._is_negative = false;
}
else {
// Normalize _offset to 0.
while (this._offset < 0) {
this._value = this._value.divide(consts.bi_10);
this._offset += 1;
}
while (this._offset > 0) {
this._value = this._value.multiply(consts.bi_10);
this._offset -= 1;
}
}
// XXX Make sure not bigger than supported. Throw if so.
}
else if (this.is_zero()) {
this._offset = -100;
this._is_negative = false;
}
else
{
// Normalize mantissa to valid range.
while (this._value.compareTo(consts.bi_man_min_value) < 0) {
this._value = this._value.multiply(consts.bi_10);
this._offset -= 1;
}
while (this._value.compareTo(consts.bi_man_max_value) > 0) {
this._value = this._value.divide(consts.bi_10);
this._offset += 1;
}
}
return this;
};
Amount.prototype.clone = function (negate) {
return this.copyTo(new Amount(), negate);
};
Amount.prototype.compareTo = function (v) {
var result;
if (!this.is_comparable(v)) {
result = Amount.NaN();
}
else if (this._is_native) {
result = this._value.compareTo(v._value);
if (result > 1)
result = 1;
else if (result < -1)
result = -1;
}
else if (this._is_negative !== v._is_negative) {
result = this._is_negative ? -1 : 1;
}
else if (this._value.equals(BigInteger.ZERO)) {
result = v._is_negative
? 1
: v._value.equals(BigInteger.ZERO)
? 0
: 1;
}
else if (v._value.equals(BigInteger.ZERO)) {
result = 1;
}
else if (this._offset > v._offset) {
result = this._is_negative ? -1 : 1;
}
else if (this._offset < v._offset) {
result = this._is_negative ? 1 : -1;
}
else {
result = this._value.compareTo(v._value);
if (result > 1)
result = 1;
else if (result < -1)
result = -1;
}
return result;
};
// Returns copy.
Amount.prototype.copyTo = function (d, negate) {
if ('object' === typeof this._value)
{
this._value.copyTo(d._value);
}
else
{
d._value = this._value;
}
d._offset = this._offset;
d._is_native = this._is_native;
d._is_negative = negate
? !this._is_negative // Negating.
: this._is_negative; // Just copying.
this._currency.copyTo(d._currency);
this._issuer.copyTo(d._issuer);
return d;
};
Amount.prototype.currency = function () {
return this._currency;
};
Amount.prototype.equals = function (d, ignore_issuer) {
if ("string" === typeof d) {
return this.equals(Amount.from_json(d));
}
if (this === d) return true;
if (d instanceof Amount) {
if (!this.is_valid() || !d.is_valid()) return false;
if (this._is_native !== d._is_native) return false;
if (!this._value.equals(d._value) || this._offset !== d._offset) {
return false;
}
if (this._is_negative !== d._is_negative) return false;
if (!this._is_native) {
if (!this._currency.equals(d._currency)) return false;
if (!ignore_issuer && !this._issuer.equals(d._issuer)) return false;
}
return true;
} else return false;
};
// Result in terms of this' currency and issuer.
Amount.prototype.divide = function (d) {
var result;
if (d.is_zero()) {
throw "divide by zero";
}
else if (this.is_zero()) {
result = this.clone();
}
else if (!this.is_valid()) {
throw new Error("Invalid dividend");
}
else if (!d.is_valid()) {
throw new Error("Invalid divisor");
}
else {
result = new Amount();
result._offset = this._offset - d._offset - 17;
result._value = this._value.multiply(consts.bi_1e17).divide(d._value).add(consts.bi_5);
result._is_native = this._is_native;
result._is_negative = this._is_negative !== d._is_negative;
result._currency = this._currency.clone();
result._issuer = this._issuer.clone();
result.canonicalize();
}
return result;
};
/**
* Calculate a ratio between two amounts.
*
* This function calculates a ratio - such as a price - between two Amount
* objects.
*
* The return value will have the same type (currency) as the numerator. This is
* a simplification, which should be sane in most cases. For example, a USD/XRP
* price would be rendered as USD.
*
* @example
* var price = buy_amount.ratio_human(sell_amount);
*
* @this {Amount} The numerator (top half) of the fraction.
* @param {Amount} denominator The denominator (bottom half) of the fraction.
* @return {Amount} The resulting ratio. Unit will be the same as numerator.
*/
Amount.prototype.ratio_human = function (denominator) {
if ("number" === typeof denominator && parseInt(denominator) === denominator) {
// Special handling of integer arguments
denominator = Amount.from_json("" + denominator + ".0");
} else {
denominator = Amount.from_json(denominator);
}
var numerator = this;
denominator = Amount.from_json(denominator);
// Special case: The denominator is a native (XRP) amount.
//
// In that case, it's going to be expressed as base units (1 XRP =
// 10^xns_precision base units).
//
// However, the unit of the denominator is lost, so when the resulting ratio
// is printed, the ratio is going to be too small by a factor of
// 10^xns_precision.
//
// To compensate, we multiply the numerator by 10^xns_precision.
if (denominator._is_native) {
numerator = numerator.clone();
numerator._value = numerator._value.multiply(consts.bi_xns_unit);
numerator.canonicalize();
}
return numerator.divide(denominator);
};
/**
* Calculate a product of two amounts.
*
* This function allows you to calculate a product between two amounts which
* retains XRPs human/external interpretation (i.e. 1 XRP = 1,000,000 base
* units).
*
* Intended use is to calculate something like: 10 USD * 10 XRP/USD = 100 XRP
*
* @example
* var sell_amount = buy_amount.product_human(price);
*
* @see Amount#ratio_human
*
* @this {Amount} The first factor of the product.
* @param {Amount} factor The second factor of the product.
* @return {Amount} The product. Unit will be the same as the first factor.
*/
Amount.prototype.product_human = function (factor) {
if ("number" === typeof factor && parseInt(factor) === factor) {
// Special handling of integer arguments
factor = Amount.from_json("" + factor + ".0");
} else {
factor = Amount.from_json(factor);
}
var product = this.multiply(factor);
// Special case: The second factor is a native (XRP) amount expressed as base
// units (1 XRP = 10^xns_precision base units).
//
// See also Amount#ratio_human.
if (factor._is_native) {
product._value = product._value.divide(consts.bi_xns_unit);
product.canonicalize();
}
return product;
}
// True if Amounts are valid and both native or non-native.
Amount.prototype.is_comparable = function (v) {
return this._value instanceof BigInteger
&& v._value instanceof BigInteger
&& this._is_native === v._is_native;
};
Amount.prototype.is_native = function () {
return this._is_native;
};
Amount.prototype.is_negative = function () {
return this._value instanceof BigInteger
? this._is_negative
: false; // NaN is not negative
};
Amount.prototype.is_positive = function () {
return !this.is_zero() && !this.is_negative();
};
// Only checks the value. Not the currency and issuer.
Amount.prototype.is_valid = function () {
return this._value instanceof BigInteger;
};
Amount.prototype.is_valid_full = function () {
return this.is_valid() && this._currency.is_valid() && this._issuer.is_valid();
};
Amount.prototype.is_zero = function () {
return this._value instanceof BigInteger
? this._value.equals(BigInteger.ZERO)
: false;
};
Amount.prototype.issuer = function () {
return this._issuer;
};
// Result in terms of this' currency and issuer.
Amount.prototype.multiply = function (v) {
var result;
if (this.is_zero()) {
result = this.clone();
}
else if (v.is_zero()) {
result = this.clone();
result._value = BigInteger.ZERO.clone();
}
else {
var v1 = this._value;
var o1 = this._offset;
var v2 = v._value;
var o2 = v._offset;
while (v1.compareTo(consts.bi_man_min_value) < 0 ) {
v1 = v1.multiply(consts.bi_10);
o1 -= 1;
}
while (v2.compareTo(consts.bi_man_min_value) < 0 ) {
v2 = v2.multiply(consts.bi_10);
o2 -= 1;
}
result = new Amount();
result._offset = o1 + o2 + 14;
result._value = v1.multiply(v2).divide(consts.bi_1e14).add(consts.bi_7);
result._is_native = this._is_native;
result._is_negative = this._is_negative !== v._is_negative;
result._currency = this._currency.clone();
result._issuer = this._issuer.clone();
result.canonicalize();
}
return result;
};
// Return a new value.
Amount.prototype.negate = function () {
return this.clone('NEGATE');
};
/**
* Tries to correctly interpret an amount as entered by a user.
*
* Examples:
*
* XRP 250 => 250000000/XRP
* 25.2 XRP => 25200000/XRP
* USD 100.40 => 100.4/USD/?
* 100 => 100000000/XRP
*/
Amount.prototype.parse_human = function (j) {
// Cast to string
j = ""+j;
// Parse
var m = j.match(/^\s*([a-z]{3})?\s*(-)?(\d+)(?:\.(\d*))?\s*([a-z]{3})?\s*$/i);
if (m) {
var currency = m[1] || m[5] || "XRP",
integer = m[3] || "0",
fraction = m[4] || "",
precision = null;
currency = currency.toUpperCase();
this._value = new BigInteger(integer);
this.set_currency(currency);
// XRP have exactly six digits of precision
if (currency === 'XRP') {
fraction = fraction.slice(0, 6);
while (fraction.length < 6) {
fraction += "0";
}
this._is_native = true;
this._value = this._value.multiply(consts.bi_xns_unit).add(new BigInteger(fraction));
}
// Other currencies have arbitrary precision
else {
while (fraction[fraction.length - 1] === "0") {
fraction = fraction.slice(0, fraction.length - 1);
}
precision = fraction.length;
this._is_native = false;
var multiplier = consts.bi_10.clone().pow(precision);
this._value = this._value.multiply(multiplier).add(new BigInteger(fraction));
this._offset = -precision;
this.canonicalize();
}
this._is_negative = !!m[2];
} else {
this._value = NaN;
}
return this;
};
Amount.prototype.parse_issuer = function (issuer) {
this._issuer.parse_json(issuer);
return this;
};
// <-> j
Amount.prototype.parse_json = function (j) {
if ('string' === typeof j) {
// .../.../... notation is not a wire format. But allowed for easier testing.
var m = j.match(/^(.+)\/(...)\/(.+)$/);
if (m) {
this._currency = Currency.from_json(m[2]);
this._issuer = UInt160.from_json(m[3]);
this.parse_value(m[1]);
}
else {
this.parse_native(j);
this._currency = new Currency();
this._issuer = new UInt160();
}
}
else if ('number' === typeof j) {
this.parse_json(""+j);
}
else if ('object' === typeof j && j instanceof Amount) {
j.copyTo(this);
}
else if ('object' === typeof j && 'value' in j) {
// Parse the passed value to sanitize and copy it.
this._currency.parse_json(j.currency); // Never XRP.
if ("string" === typeof j.issuer) this._issuer.parse_json(j.issuer);
this.parse_value(j.value);
}
else {
this._value = NaN;
}
return this;
};
// Parse a XRP value from untrusted input.
// - integer = raw units
// - float = with precision 6
// XXX Improvements: disallow leading zeros.
Amount.prototype.parse_native = function (j) {
var m;
if ('string' === typeof j)
m = j.match(/^(-?)(\d*)(\.\d{0,6})?$/);
if (m) {
if (undefined === m[3]) {
// Integer notation
this._value = new BigInteger(m[2]);
}
else {
// Float notation : values multiplied by 1,000,000.
var int_part = (new BigInteger(m[2])).multiply(consts.bi_xns_unit);
var fraction_part = (new BigInteger(m[3])).multiply(new BigInteger(String(Math.pow(10, 1+consts.xns_precision-m[3].length))));
this._value = int_part.add(fraction_part);
}
this._is_native = true;
this._offset = 0;
this._is_negative = !!m[1] && this._value.compareTo(BigInteger.ZERO) !== 0;
if (this._value.compareTo(consts.bi_xns_max) > 0)
{
this._value = NaN;
}
}
else {
this._value = NaN;
}
return this;
};
// Parse a non-native value for the json wire format.
// Requires _currency to be set!
Amount.prototype.parse_value = function (j) {
this._is_native = false;
if ('number' === typeof j) {
this._is_negative = j < 0;
this._value = new BigInteger(this._is_negative ? -j : j);
this._offset = 0;
this.canonicalize();
}
else if ('string' === typeof j) {
var i = j.match(/^(-?)(\d+)$/);
var d = !i && j.match(/^(-?)(\d*)\.(\d*)$/);
var e = !e && j.match(/^(-?)(\d*)e(-?\d+)$/);
if (e) {
// e notation
this._value = new BigInteger(e[2]);
this._offset = parseInt(e[3]);
this._is_negative = !!e[1];
this.canonicalize();
}
else if (d) {
// float notation
var integer = new BigInteger(d[2]);
var fraction = new BigInteger(d[3]);
var precision = d[3].length;
this._value = integer.multiply(consts.bi_10.clone().pow(precision)).add(fraction);
this._offset = -precision;
this._is_negative = !!d[1];
this.canonicalize();
}
else if (i) {
// integer notation
this._value = new BigInteger(i[2]);
this._offset = 0;
this._is_negative = !!i[1];
this.canonicalize();
}
else {
this._value = NaN;
}
}
else if (j instanceof BigInteger) {
this._value = j.clone();
}
else {
this._value = NaN;
}
return this;
};
Amount.prototype.set_currency = function (c) {
if ('string' === typeof c) {
this._currency.parse_json(c);
}
else
{
c.copyTo(this._currency);
}
this._is_native = this._currency.is_native();
return this;
};
Amount.prototype.set_issuer = function (issuer) {
if (issuer instanceof UInt160) {
issuer.copyTo(this._issuer);
} else {
this._issuer.parse_json(issuer);
}
return this;
};
// Result in terms of this' currency and issuer.
Amount.prototype.subtract = function (v) {
// Correctness over speed, less code has less bugs, reuse add code.
return this.add(v.negate());
};
Amount.prototype.to_number = function (allow_nan) {
var s = this.to_text(allow_nan);
return ('string' === typeof s) ? Number(s) : s;
}
// Convert only value to JSON wire format.
Amount.prototype.to_text = function (allow_nan) {
if (!(this._value instanceof BigInteger)) {
// Never should happen.
return allow_nan ? NaN : "0";
}
else if (this._is_native) {
if (this._value.compareTo(consts.bi_xns_max) > 0)
{
// Never should happen.
return allow_nan ? NaN : "0";
}
else
{
return (this._is_negative ? "-" : "") + this._value.toString();
}
}
else if (this.is_zero())
{
return "0";
}
else if (this._offset && (this._offset < -25 || this._offset > -4))
{
// Use e notation.
// XXX Clamp output.
return (this._is_negative ? "-" : "") + this._value.toString() + "e" + this._offset;
}
else
{
var val = "000000000000000000000000000" + this._value.toString() + "00000000000000000000000";
var pre = val.substring(0, this._offset + 43);
var post = val.substring(this._offset + 43);
var s_pre = pre.match(/[1-9].*$/); // Everything but leading zeros.
var s_post = post.match(/[1-9]0*$/); // Last non-zero plus trailing zeros.
return (this._is_negative ? "-" : "")
+ (s_pre ? s_pre[0] : "0")
+ (s_post ? "." + post.substring(0, 1+post.length-s_post[0].length) : "");
}
};
/**
* Format only value in a human-readable format.
*
* @example
* var pretty = amount.to_human({precision: 2});
*
* @param opts Options for formatter.
* @param opts.precision {Number} Max. number of digits after decimal point.
* @param opts.min_precision {Number} Min. number of digits after dec. point.
* @param opts.skip_empty_fraction {Boolean} Don't show fraction if it is zero,
* even if min_precision is set.
* @param opts.group_sep {Boolean|String} Whether to show a separator every n
* digits, if a string, that value will be used as the separator. Default: ","
* @param opts.group_width {Number} How many numbers will be grouped together,
* default: 3.
* @param opts.signed {Boolean|String} Whether negative numbers will have a
* prefix. If String, that string will be used as the prefix. Default: "-"
*/
Amount.prototype.to_human = function (opts)
{
opts = opts || {};
if (!this.is_valid()) return "";
// Default options
if ("undefined" === typeof opts.signed) opts.signed = true;
if ("undefined" === typeof opts.group_sep) opts.group_sep = true;
opts.group_width = opts.group_width || 3;
var order = this._is_native ? consts.xns_precision : -this._offset;
var denominator = consts.bi_10.clone().pow(order);
var int_part = this._value.divide(denominator).toString(10);
var fraction_part = this._value.mod(denominator).toString(10);
// Add leading zeros to fraction
while (fraction_part.length < order) {
fraction_part = "0" + fraction_part;
}
int_part = int_part.replace(/^0*/, '');
fraction_part = fraction_part.replace(/0*$/, '');
if (fraction_part.length || !opts.skip_empty_fraction) {
if ("number" === typeof opts.precision) {
fraction_part = fraction_part.slice(0, opts.precision);
}
if ("number" === typeof opts.min_precision) {
while (fraction_part.length < opts.min_precision) {
fraction_part += "0";
}
}
}
if (opts.group_sep) {
if ("string" !== typeof opts.group_sep) {
opts.group_sep = ',';
}
int_part = utils.chunkString(int_part, opts.group_width, true).join(opts.group_sep);
}
var formatted = '';
if (opts.signed && this._is_negative) {
if ("string" !== typeof opts.signed) {
opts.signed = '-';
}
formatted += opts.signed;
}
formatted += int_part.length ? int_part : '0';
formatted += fraction_part.length ? '.'+fraction_part : '';
return formatted;
};
Amount.prototype.to_human_full = function (opts) {
opts = opts || {};
var a = this.to_human(opts);
var c = this._currency.to_human();
var i = this._issuer.to_json(opts);
var o;
if (this._is_native)
{
o = a + "/" + c;
}
else
{
o = a + "/" + c + "/" + i;
}
return o;
};
Amount.prototype.to_json = function () {
if (this._is_native) {
return this.to_text();
}
else
{
var amount_json = {
'value' : this.to_text(),
'currency' : this._currency.to_json()
};
if (this._issuer.is_valid()) {
amount_json.issuer = this._issuer.to_json();
}
return amount_json;
}
};
Amount.prototype.to_text_full = function (opts) {
return this._value instanceof BigInteger
? this._is_native
? this.to_text() + "/XRP"
: this.to_text() + "/" + this._currency.to_json() + "/" + this._issuer.to_json(opts)
: NaN;
};
// For debugging.
Amount.prototype.not_equals_why = function (d, ignore_issuer) {
if ("string" === typeof d) {
return this.not_equals_why(Amount.from_json(d));
}
if (this === d) return false;
if (d instanceof Amount) {
if (!this.is_valid() || !d.is_valid()) return "Invalid amount.";
if (this._is_native !== d._is_native) return "Native mismatch.";
var type = this._is_native ? "XRP" : "Non-XRP";
if (!this._value.equals(d._value) || this._offset !== d._offset) {
return type+" value differs.";
}
if (this._is_negative !== d._is_negative) return type+" sign differs.";
if (!this._is_native) {
if (!this._currency.equals(d._currency)) return "Non-XRP currency differs.";
if (!ignore_issuer && !this._issuer.equals(d._issuer)) {
return "Non-XRP issuer differs.";
}
}
return false;
} else return "Wrong constructor.";
};
exports.Amount = Amount;
// DEPRECATED: Include the corresponding files instead.
exports.Currency = Currency;
exports.Seed = Seed;
exports.UInt160 = UInt160;
// vim:sw=2:sts=2:ts=8:et