From df2f73d802b5b6340c1fc5ec180ae9cb0654322a Mon Sep 17 00:00:00 2001
From: epixian <38962121+epixian@users.noreply.github.com>
Date: Fri, 16 Dec 2022 16:45:11 -0500
Subject: [PATCH 1/4] Better random country generation

Incorporates the very fast Mulberry32 PRNG algorithm into the "answer" country generation using the UTC date as the seed.
---
 src/util/answer.ts | 21 +++++++++++++++++----
 1 file changed, 17 insertions(+), 4 deletions(-)

diff --git a/src/util/answer.ts b/src/util/answer.ts
index 1b5027e..b94c429 100644
--- a/src/util/answer.ts
+++ b/src/util/answer.ts
@@ -12,10 +12,23 @@ const shuffleAdjust = today < "2022-08-01" ? "5" : "6";
 function generateKeyNew(list: any[], day: string) {
   const [year, month, date] = day.split("-");
   const dayCode = Date.UTC(parseInt(year), parseInt(month) - 1, parseInt(date));
-  const SHUFFLE_KEY = process.env.REACT_APP_SHUFFLE_KEY || "1";
-  const key =
-    Math.floor(dayCode / parseInt(SHUFFLE_KEY + shuffleAdjust)) % list.length;
-  return key;
+  return Math.floor(list.length * mulberry32(dayCode));
+}
+
+/**
+ * Mulberry32 PRNG (JS)
+ * @link https://github.com/bryc/code/blob/master/jshash/PRNGs.md#mulberry32
+ * 
+ * Ported from the original C implementation
+ * @author Tommy Ettinger
+ * @link https://gist.github.com/tommyettinger/46a874533244883189143505d203312c
+ * @license Public Domain 
+ */
+function mulberry32(a) {
+  a |= 0; a = a + 0x6D2B79F5 | 0;
+  var t = Math.imul(a ^ a >>> 15, 1 | a);
+  t = t + Math.imul(t ^ t >>> 7, 61 | t) ^ t;
+  return ((t ^ t >>> 14) >>> 0) / 4294967296;
 }
 
 const key = generateKeyNew(countryData, today);

From 939ce6482b11baec8016390521d82c8227d6c9ca Mon Sep 17 00:00:00 2001
From: epixian <38962121+epixian@users.noreply.github.com>
Date: Mon, 13 Mar 2023 17:35:33 -0400
Subject: [PATCH 2/4] Add type

---
 src/util/answer.ts | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/util/answer.ts b/src/util/answer.ts
index b94c429..1725912 100644
--- a/src/util/answer.ts
+++ b/src/util/answer.ts
@@ -24,7 +24,7 @@ function generateKeyNew(list: any[], day: string) {
  * @link https://gist.github.com/tommyettinger/46a874533244883189143505d203312c
  * @license Public Domain 
  */
-function mulberry32(a) {
+function mulberry32(a: number) {
   a |= 0; a = a + 0x6D2B79F5 | 0;
   var t = Math.imul(a ^ a >>> 15, 1 | a);
   t = t + Math.imul(t ^ t >>> 7, 61 | t) ^ t;

From 204ed6a3784f526238eca9ec01e3cdf569937bd8 Mon Sep 17 00:00:00 2001
From: epixian <38962121+epixian@users.noreply.github.com>
Date: Mon, 13 Mar 2023 18:18:39 -0400
Subject: [PATCH 3/4] Add parentheses

---
 src/util/answer.ts | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/src/util/answer.ts b/src/util/answer.ts
index 1725912..f4710d9 100644
--- a/src/util/answer.ts
+++ b/src/util/answer.ts
@@ -26,9 +26,9 @@ function generateKeyNew(list: any[], day: string) {
  */
 function mulberry32(a: number) {
   a |= 0; a = a + 0x6D2B79F5 | 0;
-  var t = Math.imul(a ^ a >>> 15, 1 | a);
-  t = t + Math.imul(t ^ t >>> 7, 61 | t) ^ t;
-  return ((t ^ t >>> 14) >>> 0) / 4294967296;
+  var t = Math.imul(a ^ (a >>> 15), 1 | a);
+  t = t + Math.imul(t ^ (t >>> 7), 61 | t) ^ t;
+  return ((t ^ (t >>> 14)) >>> 0) / 4294967296;
 }
 
 const key = generateKeyNew(countryData, today);

From 25be1175bbba5d03f4eea5b71942c40de727c524 Mon Sep 17 00:00:00 2001
From: epixian <38962121+epixian@users.noreply.github.com>
Date: Mon, 13 Mar 2023 18:22:50 -0400
Subject: [PATCH 4/4] Remove unused

---
 src/util/answer.ts | 2 --
 1 file changed, 2 deletions(-)

diff --git a/src/util/answer.ts b/src/util/answer.ts
index f4710d9..9aeef0a 100644
--- a/src/util/answer.ts
+++ b/src/util/answer.ts
@@ -7,8 +7,6 @@ countryData.sort((a, b) => {
   return a.properties.FLAG[1].localeCompare(b.properties.FLAG[1]);
 });
 
-const shuffleAdjust = today < "2022-08-01" ? "5" : "6";
-
 function generateKeyNew(list: any[], day: string) {
   const [year, month, date] = day.split("-");
   const dayCode = Date.UTC(parseInt(year), parseInt(month) - 1, parseInt(date));