urbit-ob

commit 796312ec3ec3a5098ea25a0f291711d31c0f97cf
parent a23d08314790f6edbe7f0df9bc64c00a23d4cfd0
Author: Jared Tobin <jared@jtobin.io>
Date:   Mon,  8 Oct 2018 10:01:32 +1300

Add hex2patq and patq2hex.

Plus a sanity check.

Diffstat:
M
src/index.js
 | 
25
++++++++++++++++++++++++-
M
test/core.test.js
 | 
6
++++++

2 files changed, 30 insertions(+), 1 deletion(-)
diff --git a/src/index.js b/src/index.js
@@ -4,7 +4,7 @@
 
 const bnjs = require('bn.js')
 const { reduce, concat, chunk, isUndefined,
-        isString, every, map } = require('lodash')
+        isString, every, map, split } = require('lodash')
 
 const raku = [
   3077398253,
@@ -51,6 +51,12 @@ remlysfynwerrycsugnysnyllyndyndemluxfedsedbecmun\
 lyrtesmudnytbyrsenwegfyrmurtelreptegpecnelnevfes\
 `
 
+// split string at the indicated index
+const splitAt = (index, str) => [str.slice(0, index), str.slice(index)];
+
+// convert a decimal number to a hex string
+const dec2hex = dec => dec.toString(16).padStart(2, '0')
+
 // groups suffixes into array of syllables
 const suffixes = suf.match(/.{1,3}/g)
 
@@ -398,6 +404,21 @@ const patq = (n) => {
     acc + (acc === '~' ? '' : '-') + name(elem), '~')
 }
 
+hex2patq = hex => patq(new bnjs(hex, 'hex'))
+
+patq2hex = str => {
+  const chunks = split(str.slice(1), '-')
+  const splat = map(chunks, chunk => {
+    let syls = splitAt(3, chunk)
+    let hex =
+      syls[1] === ''
+      ? dec2hex(getSuffixIndex(syls[0]))
+      : dec2hex(getPrefixIndex(syls[0])) +
+        dec2hex(getSuffixIndex(syls[1]))
+    return hex
+  })
+  return splat.join('')
+}
 
 // returns the class of a ship from it's name
 const tierOfpatp = name => {
@@ -544,6 +565,8 @@ module.exports = {
 
   patp: patp,
   patq: patq,
+  hex2patq: hex2patq,
+  patq2hex: patq2hex,
 
   sein: sein,
   _clan: clan,
diff --git a/test/core.test.js b/test/core.test.js
@@ -155,6 +155,12 @@ test('patq correctly encodes 0x1010101010101010102 as @q', () => {
   expect(ob.patq(input)).toBe(expected);
 });
 
+test('hex2patq works', () => {
+  let hex = '6d7920617765736f6d65207572626974207469636b65742c206920616d20736f206c75636b79';
+  let expected = '~tastud-holruc-sidwet-salpel-taswet-holdeg-paddec-davdut-holdut-davwex-balwet-divwen-holdet-holruc-taslun-salpel-holtux-dacwex-baltud';
+  expect(ob.hex2patq(hex)).toBe(expected);
+})
+
 test('clan works as expected', () => {
   expect(ob._clan(new bnjs(0))).toBe('czar');
   expect(ob._clan(new bnjs(255))).toBe('czar');