From 9a48fd81a36634b41c55562eba410823448f9f68 Mon Sep 17 00:00:00 2001
From: Samantaz Fox <coding@samantaz.fr>
Date: Thu, 18 Nov 2021 17:37:33 +0100
Subject: [PATCH] i18n: Add i18next plurals base sets

---
 src/invidious/helpers/i18next.cr | 83 ++++++++++++++++++++++++++++++++
 1 file changed, 83 insertions(+)
 create mode 100644 src/invidious/helpers/i18next.cr

diff --git a/src/invidious/helpers/i18next.cr b/src/invidious/helpers/i18next.cr
new file mode 100644
index 00000000..16ca594b
--- /dev/null
+++ b/src/invidious/helpers/i18next.cr
@@ -0,0 +1,83 @@
+# I18next-compatible implementation of plural forms
+#
+module I18next::Plurals
+  # -----------------------------------
+  #  I18next plural forms definition
+  # -----------------------------------
+
+  private enum PluralForms
+    # One singular, one plural forms
+    Single_gt_one  = 1 # E.g: French
+    Single_not_one = 2 # E.g: English
+
+    # No plural forms (E.g: Azerbaijani)
+    None = 3
+
+    # One singular, two plural forms
+    Dual_Slavic = 4 # E.g: Russian
+
+    # Special cases (rules used by only one or two language(s))
+    Special_Arabic           =  5
+    Special_Czech_Slovak     =  6
+    Special_Polish_Kashubian =  7
+    Special_Welsh            =  8
+    Special_Irish            = 10
+    Special_Scottish_Gaelic  = 11
+    Special_Icelandic        = 12
+    Special_Javanese         = 13
+    Special_Cornish          = 14
+    Special_Lithuanian       = 15
+    Special_Latvian          = 16
+    Special_Macedonian       = 17
+    Special_Mandinka         = 18
+    Special_Maltese          = 19
+    Special_Romanian         = 20
+    Special_Slovenian        = 21
+    Special_Hebrew           = 22
+  end
+
+  private PLURAL_SETS = {
+    PluralForms::Single_gt_one => [
+      "ach", "ak", "am", "arn", "br", "fil", "fr", "gun", "ln", "mfe", "mg",
+      "mi", "oc", "pt", "pt-BR", "tg", "tl", "ti", "tr", "uz", "wa",
+    ],
+    PluralForms::Single_not_one => [
+      "af", "an", "ast", "az", "bg", "bn", "ca", "da", "de", "dev", "el", "en",
+      "eo", "es", "et", "eu", "fi", "fo", "fur", "fy", "gl", "gu", "ha", "hi",
+      "hu", "hy", "ia", "it", "kk", "kn", "ku", "lb", "mai", "ml", "mn", "mr",
+      "nah", "nap", "nb", "ne", "nl", "nn", "no", "nso", "pa", "pap", "pms",
+      "ps", "pt-PT", "rm", "sco", "se", "si", "so", "son", "sq", "sv", "sw",
+      "ta", "te", "tk", "ur", "yo",
+    ],
+    PluralForms::None => [
+      "ay", "bo", "cgg", "fa", "ht", "id", "ja", "jbo", "ka", "km", "ko", "ky",
+      "lo", "ms", "sah", "su", "th", "tt", "ug", "vi", "wo", "zh",
+    ],
+    PluralForms::Dual_Slavic => [
+      "be", "bs", "cnr", "dz", "hr", "ru", "sr", "uk",
+    ],
+  }
+
+  private PLURAL_SINGLES = {
+    "ar"  => PluralForms::Special_Arabic,
+    "cs"  => PluralForms::Special_Czech_Slovak,
+    "csb" => PluralForms::Special_Polish_Kashubian,
+    "cy"  => PluralForms::Special_Welsh,
+    "ga"  => PluralForms::Special_Irish,
+    "gd"  => PluralForms::Special_Scottish_Gaelic,
+    "he"  => PluralForms::Special_Hebrew,
+    "is"  => PluralForms::Special_Icelandic,
+    "iw"  => PluralForms::Special_Hebrew,
+    "jv"  => PluralForms::Special_Javanese,
+    "kw"  => PluralForms::Special_Cornish,
+    "lt"  => PluralForms::Special_Lithuanian,
+    "lv"  => PluralForms::Special_Latvian,
+    "mk"  => PluralForms::Special_Macedonian,
+    "mnk" => PluralForms::Special_Mandinka,
+    "mt"  => PluralForms::Special_Maltese,
+    "pl"  => PluralForms::Special_Polish_Kashubian,
+    "ro"  => PluralForms::Special_Romanian,
+    "sk"  => PluralForms::Special_Czech_Slovak,
+    "sl"  => PluralForms::Special_Slovenian,
+  }
+end