From bb0e45937774c318d6a904094b652ce59a197c1d Mon Sep 17 00:00:00 2001
From: Chris Wilkinson <c.wilkinson@elifesciences.org>
Date: Fri, 26 Jul 2024 11:24:00 +0100
Subject: [PATCH] Fall back to by population when there are cities with the
 same name in different time zones

Refs #31
---
 src/lib/Iso3166.ts   | 18 ++++++++++++++----
 test/Iso3166.test.ts |  1 +
 2 files changed, 15 insertions(+), 4 deletions(-)

diff --git a/src/lib/Iso3166.ts b/src/lib/Iso3166.ts
index 1633e5c..3fe9d1c 100644
--- a/src/lib/Iso3166.ts
+++ b/src/lib/Iso3166.ts
@@ -35,11 +35,21 @@ export const guessCountry: (location: string) => Option.Option<Alpha2Code> = flo
       ),
       Option.orElse(() =>
         Option.map(
-          Array.findFirst(rawTimeZones, timezone =>
-            Array.some(
-              timezone.mainCities,
-              mainCity => diacritics.remove(location).toLowerCase() === diacritics.remove(mainCity).toLowerCase(),
+          Array.matchLeft(
+            Array.filter(rawTimeZones, timezone =>
+              Array.some(
+                timezone.mainCities,
+                mainCity => diacritics.remove(location).toLowerCase() === diacritics.remove(mainCity).toLowerCase(),
+              ),
             ),
+            {
+              onEmpty: () => Option.none(),
+              onNonEmpty: (head, tail) =>
+                Array.match(tail, {
+                  onEmpty: () => Option.some(head),
+                  onNonEmpty: Option.none,
+                }),
+            },
           ),
           timeZone => timeZone.countryCode,
         ),
diff --git a/test/Iso3166.test.ts b/test/Iso3166.test.ts
index 2d0bf08..0df23ad 100644
--- a/test/Iso3166.test.ts
+++ b/test/Iso3166.test.ts
@@ -23,6 +23,7 @@ describe('guessCountry', () => {
     ['Québec', 'CA'],
     ['Rio de Janeiro, Brazil.', 'BR'],
     ['Sunnyvale, California', 'US'],
+    ['Sydney', 'AU'],
     ['The UK', 'GB'],
     ['UK', 'GB'],
     ['U.K.', 'GB'],