// Generated by make_intl_data.py. DO NOT EDIT.
// Version: CLDR-48.2
// URL: https://unicode.org/Public/cldr/48.2/cldr-common-48.2.zip

#include "mozilla/Assertions.h"
#include "mozilla/Span.h"
#include "mozilla/TextUtils.h"

#include <algorithm>
#include <cstdint>
#include <cstring>
#include <iterator>
#include <string>

#include "mozilla/intl/Locale.h"

using namespace mozilla::intl::LanguageTagLimits;

template <size_t Length, size_t TagLength, size_t SubtagLength>
static inline bool HasReplacement(
    const char (&subtags)[Length][TagLength],
    const mozilla::intl::LanguageTagSubtag<SubtagLength>& subtag) {
  MOZ_ASSERT(subtag.Length() == TagLength - 1,
             "subtag must have the same length as the list of subtags");

  const char* ptr = subtag.Span().data();
  return std::binary_search(std::begin(subtags), std::end(subtags), ptr,
                            [](const char* a, const char* b) {
                              return memcmp(a, b, TagLength - 1) < 0;
                            });
}

template <size_t Length, size_t TagLength, size_t SubtagLength>
static inline const char* SearchReplacement(
    const char (&subtags)[Length][TagLength], const char* (&aliases)[Length],
    const mozilla::intl::LanguageTagSubtag<SubtagLength>& subtag) {
  MOZ_ASSERT(subtag.Length() == TagLength - 1,
             "subtag must have the same length as the list of subtags");

  const char* ptr = subtag.Span().data();
  auto p = std::lower_bound(std::begin(subtags), std::end(subtags), ptr,
                            [](const char* a, const char* b) {
                              return memcmp(a, b, TagLength - 1) < 0;
                            });
  if (p != std::end(subtags) && memcmp(*p, ptr, TagLength - 1) == 0) {
    return aliases[std::distance(std::begin(subtags), p)];
  }
  return nullptr;
}

#ifdef DEBUG
static bool IsAsciiLowercaseAlphanumeric(char c) {
  return mozilla::IsAsciiLowercaseAlpha(c) || mozilla::IsAsciiDigit(c);
}

static bool IsAsciiLowercaseAlphanumericOrDash(char c) {
  return IsAsciiLowercaseAlphanumeric(c) || c == '-';
}

static bool IsCanonicallyCasedLanguageTag(mozilla::Span<const char> span) {
  return std::all_of(span.begin(), span.end(),
                     mozilla::IsAsciiLowercaseAlpha<char>);
}

static bool IsCanonicallyCasedScriptTag(mozilla::Span<const char> span) {
  return mozilla::IsAsciiUppercaseAlpha(span[0]) &&
         std::all_of(span.begin() + 1, span.end(),
                     mozilla::IsAsciiLowercaseAlpha<char>);
}

static bool IsCanonicallyCasedRegionTag(mozilla::Span<const char> span) {
  return std::all_of(span.begin(), span.end(),
                     mozilla::IsAsciiUppercaseAlpha<char>) ||
         std::all_of(span.begin(), span.end(), mozilla::IsAsciiDigit<char>);
}

static bool IsCanonicallyCasedVariantTag(mozilla::Span<const char> span) {
  return std::all_of(span.begin(), span.end(), IsAsciiLowercaseAlphanumeric);
}

static bool IsCanonicallyCasedUnicodeKey(mozilla::Span<const char> key) {
  return std::all_of(key.begin(), key.end(), IsAsciiLowercaseAlphanumeric);
}

static bool IsCanonicallyCasedUnicodeType(mozilla::Span<const char> type) {
  return std::all_of(type.begin(), type.end(),
                     IsAsciiLowercaseAlphanumericOrDash);
}

static bool IsCanonicallyCasedTransformKey(mozilla::Span<const char> key) {
  return std::all_of(key.begin(), key.end(), IsAsciiLowercaseAlphanumeric);
}

static bool IsCanonicallyCasedTransformType(mozilla::Span<const char> type) {
  return std::all_of(type.begin(), type.end(),
                     IsAsciiLowercaseAlphanumericOrDash);
}
#endif

// Mappings from language subtags to preferred values.
// Derived from CLDR Supplemental Data, version 48.2.
// https://unicode.org/Public/cldr/48.2/cldr-common-48.2.zip
bool mozilla::intl::Locale::LanguageMapping(LanguageSubtag& language) {
  MOZ_ASSERT(IsStructurallyValidLanguageTag(language.Span()));
  MOZ_ASSERT(IsCanonicallyCasedLanguageTag(language.Span()));

  if (language.Length() == 2) {
    static const char languages[8][3] = {
      "bh", "in", "iw", "ji", "jw", "mo", "tl", "tw",
    };
    static const char* aliases[8] = {
      "bho", "id", "he", "yi", "jv", "ro", "fil", "ak",
    };

    if (const char* replacement = SearchReplacement(languages, aliases, language)) {
      language.Set(mozilla::MakeStringSpan(replacement));
      return true;
    }
    return false;
  }

  if (language.Length() == 3) {
    static const char languages[420][4] = {
      "aam", "aar", "abk", "adp", "afr", "agp", "ais", "ajp", "ajt", "aju",
      "aka", "alb", "als", "amh", "ara", "arb", "arg", "arm", "asd", "asm",
      "aue", "ava", "ave", "aym", "ayr", "ayx", "aze", "azj", "bak", "bam",
      "baq", "baz", "bcc", "bcl", "bel", "ben", "bgm", "bhk", "bic", "bih",
      "bis", "bjd", "bjq", "bkb", "blg", "bod", "bos", "bre", "btb", "bul",
      "bur", "bxk", "bxr", "cat", "ccq", "ces", "cha", "che", "chi", "chu",
      "chv", "cjr", "cka", "cld", "cls", "cmk", "cmn", "cor", "cos", "coy",
      "cqu", "cre", "cwd", "cym", "cze", "daf", "dan", "dap", "dek", "deu",
      "dgo", "dhd", "dik", "diq", "dit", "div", "djl", "dkl", "drh", "drr",
      "dud", "duj", "dut", "dwl", "dzo", "ekk", "ell", "elp", "emk", "eng",
      "epo", "esk", "est", "eus", "ewe", "fao", "fas", "fat", "fij", "fin",
      "fra", "fre", "fry", "fuc", "ful", "gav", "gaz", "gbc", "gbo", "geo",
      "ger", "gfx", "ggn", "ggo", "ggr", "gio", "gla", "gle", "glg", "gli",
      "glv", "gno", "gom", "gre", "grn", "gti", "gug", "guj", "guv", "gya",
      "hat", "hau", "hdn", "hea", "heb", "her", "him", "hin", "hmo", "hrr",
      "hrv", "hun", "hye", "ibi", "ibo", "ice", "ido", "iii", "ike", "iku",
      "ile", "ill", "ilw", "ina", "ind", "ipk", "isl", "ita", "izi", "jar",
      "jav", "jeg", "jpn", "kal", "kan", "kas", "kat", "kau", "kaz", "kdv",
      "kgc", "kgd", "kgh", "kgm", "khk", "khm", "kik", "kin", "kir", "kmr",
      "knc", "kng", "koj", "kom", "kon", "kor", "kpp", "kpv", "krm", "ktr",
      "kua", "kur", "kvs", "kwq", "kxe", "kxl", "kzh", "kzj", "kzt", "lak",
      "lao", "lat", "lav", "lbk", "leg", "lii", "lim", "lin", "lit", "llo",
      "lmm", "ltz", "lub", "lug", "lvs", "mac", "mah", "mal", "mao", "mar",
      "may", "meg", "mgx", "mhr", "mkd", "mlg", "mlt", "mnt", "mof", "mol",
      "mon", "mri", "msa", "mst", "mup", "mwd", "mwj", "mya", "myd", "myt",
      "nad", "nau", "nav", "nbf", "nbl", "nbx", "ncp", "nde", "ndo", "nep",
      "nld", "nln", "nlr", "nno", "nns", "nnx", "nob", "nom", "noo", "nor",
      "npi", "nte", "nts", "nxu", "nya", "oci", "ojg", "oji", "ori", "orm",
      "ory", "oss", "oun", "pan", "pat", "pbu", "pcr", "per", "pes", "pli",
      "plt", "pmc", "pmk", "pmu", "pnb", "pol", "por", "ppa", "ppr", "prp",
      "pry", "pus", "puz", "que", "quz", "rmr", "rmy", "roh", "ron", "rum",
      "run", "rus", "sag", "san", "sap", "sca", "scc", "scr", "sgl", "sin",
      "skk", "slk", "slo", "slv", "smd", "sme", "smo", "sna", "snb", "snd",
      "som", "sot", "spa", "spy", "sqi", "src", "srd", "srp", "ssw", "sul",
      "sum", "sun", "swa", "swe", "swh", "szd", "tah", "tam", "tat", "tdu",
      "tel", "tgg", "tgk", "tgl", "tha", "thc", "thw", "thx", "tib", "tid",
      "tie", "tir", "tkk", "tlw", "tmk", "tmp", "tne", "ton", "tpw", "tsf",
      "tsn", "tso", "ttq", "tuk", "tur", "twi", "uig", "ukr", "umu", "unp",
      "uok", "urd", "uzb", "uzn", "ven", "vie", "vol", "wel", "wgw", "wit",
      "wiw", "wln", "wol", "xba", "xho", "xia", "xkh", "xpe", "xrq", "xsj",
      "xsl", "xss", "ybd", "ydd", "yen", "yid", "yiy", "yma", "ymt", "yor",
      "yos", "yuu", "zai", "zha", "zho", "zir", "zkb", "zsm", "zul", "zyb",
    };
    static const char* aliases[420] = {
      "aas",  "aa",  "ab",  "dz",  "af", "apf", "ami", "apc", "aeb", "jrb",
       "ak",  "sq",  "sq",  "am",  "ar",  "ar",  "an",  "hy", "snz",  "as",
      "ktz",  "av",  "ae",  "ay",  "ay", "nun",  "az",  "az",  "ba",  "bm",
       "eu", "nvo", "bal", "bik",  "be",  "bn", "bcg", "fbl", "bir", "bho",
       "bi", "drl", "bzc", "ebk", "iba",  "bo",  "bs",  "br", "beb",  "bg",
       "my", "luy", "bua",  "ca", "rki",  "cs",  "ch",  "ce",  "zh",  "cu",
       "cv", "mom", "cmr", "syr",  "sa", "xch",  "zh",  "kw",  "co", "pij",
      "quh",  "cr",  "cr",  "cy",  "cs", "dnj",  "da", "njz", "sqm",  "de",
      "doi", "mwr", "din", "zza", "dif",  "dv", "dze", "aqd",  "mn", "kzk",
      "uth", "dwu",  "nl", "dbt",  "dz",  "et",  "el", "amq", "man",  "en",
       "eo",  "ik",  "et",  "eu",  "ee",  "fo",  "fa",  "ak",  "fj",  "fi",
       "fr",  "fr",  "fy",  "ff",  "ff", "dev",  "om", "wny", "grb",  "ka",
       "de", "vaj", "gvr", "esg", "gtu", "aou",  "gd",  "ga",  "gl", "kzk",
       "gv", "gon", "kok",  "el",  "gn", "nyc",  "gn",  "gu", "duz", "gba",
       "ht",  "ha", "hai", "hmn",  "he",  "hz", "srx",  "hi",  "ho", "jal",
       "hr",  "hu",  "hy", "opa",  "ig",  "is",  "io",  "ii",  "iu",  "iu",
       "ie", "ilm", "gal",  "ia",  "id",  "ik",  "is",  "it", "eza", "jgk",
       "jv", "oyb",  "ja",  "kl",  "kn",  "ks",  "ka",  "kr",  "kk", "zkd",
      "tdf", "ncq", "kml", "plu",  "mn",  "km",  "ki",  "rw",  "ky",  "ku",
       "kr",  "kg", "kwv",  "kv",  "kg",  "ko", "jkm",  "kv", "bmf", "dtp",
       "kj",  "ku", "gdj", "yam", "tvd", "kru", "dgl", "dtp", "dtp", "ksp",
       "lo",  "la",  "lv", "bnc", "enl", "raq",  "li",  "ln",  "lt", "ngt",
      "rmx",  "lb",  "lu",  "lg",  "lv",  "mk",  "mh",  "ml",  "mi",  "mr",
       "ms", "cir", "jbk", "chm",  "mk",  "mg",  "mt", "wnn", "xnt",  "ro",
       "mn",  "mi",  "ms", "mry", "raj", "dmw", "vaj",  "my", "aog", "mry",
      "xny",  "na",  "nv", "nru",  "nr", "gll", "kdz",  "nd",  "ng",  "ne",
       "nl", "azd", "nrk",  "nn", "nbr", "ngv",  "nb", "cbr", "dtd",  "no",
       "ne", "eko", "pij", "bpp",  "ny",  "oc",  "oj",  "oj",  "or",  "om",
       "or",  "os", "vaj",  "pa", "kxr",  "ps", "adx",  "fa",  "fa",  "pi",
       "mg", "huw", "crr", "phr", "lah",  "pl",  "pt", "bfy", "lcq",  "gu",
      "prt",  "ps", "pub",  "qu",  "qu", "emx", "rom",  "rm",  "ro",  "ro",
       "rn",  "ru",  "sg",  "sa", "aqt", "hle",  "sr",  "hr", "isk",  "si",
      "oyb",  "sk",  "sk",  "sl", "kmb",  "se",  "sm",  "sn", "iba",  "sd",
       "so",  "st",  "es", "kln",  "sq",  "sc",  "sc",  "sr",  "ss", "sgd",
      "ulw",  "su",  "sw",  "sv",  "sw", "umi",  "ty",  "ta",  "tt", "dtp",
       "te", "bjp",  "tg", "fil",  "th", "tpo", "ola", "oyb",  "bo", "itd",
      "ras",  "ti", "twm", "weo", "tdg", "tyj", "kak",  "to", "tpn", "taj",
       "tn",  "ts", "tmh",  "tk",  "tr",  "ak",  "ug",  "uk", "del", "wro",
      "ema",  "ur",  "uz",  "uz",  "ve",  "vi",  "vo",  "cy", "wgb", "nol",
      "nwo",  "wa",  "wo", "cax",  "xh", "acn", "waw", "kpe", "dmw", "suj",
      "den", "zko", "rki",  "yi", "ynq",  "yi", "yrm", "lrr", "mtm",  "yo",
      "zom", "yug", "zap",  "za",  "zh", "scv", "kjh",  "ms",  "zu",  "za",
    };

    if (const char* replacement = SearchReplacement(languages, aliases, language)) {
      language.Set(mozilla::MakeStringSpan(replacement));
      return true;
    }
    return false;
  }

  return false;
}

// Language subtags with complex mappings.
// Derived from CLDR Supplemental Data, version 48.2.
// https://unicode.org/Public/cldr/48.2/cldr-common-48.2.zip
bool mozilla::intl::Locale::ComplexLanguageMapping(const LanguageSubtag& language) {
  MOZ_ASSERT(IsStructurallyValidLanguageTag(language.Span()));
  MOZ_ASSERT(IsCanonicallyCasedLanguageTag(language.Span()));

  if (language.Length() == 2) {
    return language.EqualTo("sh");
  }

  if (language.Length() == 3) {
    static const char languages[6][4] = {
      "cnr", "drw", "hbs", "prs", "swc", "tnf",
    };

    return HasReplacement(languages, language);
  }

  return false;
}

// Mappings from script subtags to preferred values.
// Derived from CLDR Supplemental Data, version 48.2.
// https://unicode.org/Public/cldr/48.2/cldr-common-48.2.zip
bool mozilla::intl::Locale::ScriptMapping(ScriptSubtag& script) {
  MOZ_ASSERT(IsStructurallyValidScriptTag(script.Span()));
  MOZ_ASSERT(IsCanonicallyCasedScriptTag(script.Span()));

  {
    if (script.EqualTo("Qaai")) {
      script.Set(mozilla::MakeStringSpan("Zinh"));
      return true;
    }
    return false;
  }
}

// Mappings from region subtags to preferred values.
// Derived from CLDR Supplemental Data, version 48.2.
// https://unicode.org/Public/cldr/48.2/cldr-common-48.2.zip
bool mozilla::intl::Locale::RegionMapping(RegionSubtag& region) {
  MOZ_ASSERT(IsStructurallyValidRegionTag(region.Span()));
  MOZ_ASSERT(IsCanonicallyCasedRegionTag(region.Span()));

  if (region.Length() == 2) {
    static const char regions[23][3] = {
      "BU", "CS", "CT", "DD", "DY", "FQ", "FX", "HV", "JT", "MI",
      "NH", "NQ", "PU", "PZ", "QU", "RH", "TP", "UK", "VD", "WK",
      "YD", "YU", "ZR",
    };
    static const char* aliases[23] = {
      "MM", "RS", "KI", "DE", "BJ", "AQ", "FR", "BF", "UM", "UM",
      "VU", "AQ", "UM", "PA", "EU", "ZW", "TL", "GB", "VN", "UM",
      "YE", "RS", "CD",
    };

    if (const char* replacement = SearchReplacement(regions, aliases, region)) {
      region.Set(mozilla::MakeStringSpan(replacement));
      return true;
    }
    return false;
  }

  {
    static const char regions[300][4] = {
      "004", "008", "010", "012", "016", "020", "024", "028", "031", "032",
      "036", "040", "044", "048", "050", "051", "052", "056", "060", "062",
      "064", "068", "070", "072", "074", "076", "084", "086", "090", "092",
      "096", "100", "104", "108", "112", "116", "120", "124", "132", "136",
      "140", "144", "148", "152", "156", "158", "162", "166", "170", "174",
      "175", "178", "180", "184", "188", "191", "192", "196", "203", "204",
      "208", "212", "214", "218", "222", "226", "230", "231", "232", "233",
      "234", "238", "239", "242", "246", "248", "249", "250", "254", "258",
      "260", "262", "266", "268", "270", "275", "276", "278", "280", "288",
      "292", "296", "300", "304", "308", "312", "316", "320", "324", "328",
      "332", "334", "336", "340", "344", "348", "352", "356", "360", "364",
      "368", "372", "376", "380", "384", "388", "392", "398", "400", "404",
      "408", "410", "414", "417", "418", "422", "426", "428", "430", "434",
      "438", "440", "442", "446", "450", "454", "458", "462", "466", "470",
      "474", "478", "480", "484", "492", "496", "498", "499", "500", "504",
      "508", "512", "516", "520", "524", "528", "531", "533", "534", "535",
      "540", "548", "554", "558", "562", "566", "570", "574", "578", "580",
      "581", "583", "584", "585", "586", "591", "598", "600", "604", "608",
      "612", "616", "620", "624", "626", "630", "634", "638", "642", "643",
      "646", "652", "654", "659", "660", "662", "663", "666", "670", "674",
      "678", "682", "686", "688", "690", "694", "702", "703", "704", "705",
      "706", "710", "716", "720", "724", "728", "729", "732", "736", "740",
      "744", "748", "752", "756", "760", "762", "764", "768", "772", "776",
      "780", "784", "788", "792", "795", "796", "798", "800", "804", "807",
      "818", "826", "830", "831", "832", "833", "834", "840", "850", "854",
      "858", "860", "862", "876", "882", "886", "887", "891", "894", "958",
      "959", "960", "962", "963", "964", "965", "966", "967", "968", "969",
      "970", "971", "972", "973", "974", "975", "976", "977", "978", "979",
      "980", "981", "982", "983", "984", "985", "986", "987", "988", "989",
      "990", "991", "992", "993", "994", "995", "996", "997", "998", "999",
    };
    static const char* aliases[300] = {
       "AF",  "AL",  "AQ",  "DZ",  "AS",  "AD",  "AO",  "AG",  "AZ",  "AR",
       "AU",  "AT",  "BS",  "BH",  "BD",  "AM",  "BB",  "BE",  "BM", "034",
       "BT",  "BO",  "BA",  "BW",  "BV",  "BR",  "BZ",  "IO",  "SB",  "VG",
       "BN",  "BG",  "MM",  "BI",  "BY",  "KH",  "CM",  "CA",  "CV",  "KY",
       "CF",  "LK",  "TD",  "CL",  "CN",  "TW",  "CX",  "CC",  "CO",  "KM",
       "YT",  "CG",  "CD",  "CK",  "CR",  "HR",  "CU",  "CY",  "CZ",  "BJ",
       "DK",  "DM",  "DO",  "EC",  "SV",  "GQ",  "ET",  "ET",  "ER",  "EE",
       "FO",  "FK",  "GS",  "FJ",  "FI",  "AX",  "FR",  "FR",  "GF",  "PF",
       "TF",  "DJ",  "GA",  "GE",  "GM",  "PS",  "DE",  "DE",  "DE",  "GH",
       "GI",  "KI",  "GR",  "GL",  "GD",  "GP",  "GU",  "GT",  "GN",  "GY",
       "HT",  "HM",  "VA",  "HN",  "HK",  "HU",  "IS",  "IN",  "ID",  "IR",
       "IQ",  "IE",  "IL",  "IT",  "CI",  "JM",  "JP",  "KZ",  "JO",  "KE",
       "KP",  "KR",  "KW",  "KG",  "LA",  "LB",  "LS",  "LV",  "LR",  "LY",
       "LI",  "LT",  "LU",  "MO",  "MG",  "MW",  "MY",  "MV",  "ML",  "MT",
       "MQ",  "MR",  "MU",  "MX",  "MC",  "MN",  "MD",  "ME",  "MS",  "MA",
       "MZ",  "OM",  "NA",  "NR",  "NP",  "NL",  "CW",  "AW",  "SX",  "BQ",
       "NC",  "VU",  "NZ",  "NI",  "NE",  "NG",  "NU",  "NF",  "NO",  "MP",
       "UM",  "FM",  "MH",  "PW",  "PK",  "PA",  "PG",  "PY",  "PE",  "PH",
       "PN",  "PL",  "PT",  "GW",  "TL",  "PR",  "QA",  "RE",  "RO",  "RU",
       "RW",  "BL",  "SH",  "KN",  "AI",  "LC",  "MF",  "PM",  "VC",  "SM",
       "ST",  "SA",  "SN",  "RS",  "SC",  "SL",  "SG",  "SK",  "VN",  "SI",
       "SO",  "ZA",  "ZW",  "YE",  "ES",  "SS",  "SD",  "EH",  "SD",  "SR",
       "SJ",  "SZ",  "SE",  "CH",  "SY",  "TJ",  "TH",  "TG",  "TK",  "TO",
       "TT",  "AE",  "TN",  "TR",  "TM",  "TC",  "TV",  "UG",  "UA",  "MK",
       "EG",  "GB",  "JE",  "GG",  "JE",  "IM",  "TZ",  "US",  "VI",  "BF",
       "UY",  "UZ",  "VE",  "WF",  "WS",  "YE",  "YE",  "RS",  "ZM",  "AA",
       "QM",  "QN",  "QP",  "QQ",  "QR",  "QS",  "QT",  "EU",  "QV",  "QW",
       "QX",  "QY",  "QZ",  "XA",  "XB",  "XC",  "XD",  "XE",  "XF",  "XG",
       "XH",  "XI",  "XJ",  "XK",  "XL",  "XM",  "XN",  "XO",  "XP",  "XQ",
       "XR",  "XS",  "XT",  "XU",  "XV",  "XW",  "XX",  "XY",  "XZ",  "ZZ",
    };

    if (const char* replacement = SearchReplacement(regions, aliases, region)) {
      region.Set(mozilla::MakeStringSpan(replacement));
      return true;
    }
    return false;
  }
}

// Region subtags with complex mappings.
// Derived from CLDR Supplemental Data, version 48.2.
// https://unicode.org/Public/cldr/48.2/cldr-common-48.2.zip
bool mozilla::intl::Locale::ComplexRegionMapping(const RegionSubtag& region) {
  MOZ_ASSERT(IsStructurallyValidRegionTag(region.Span()));
  MOZ_ASSERT(IsCanonicallyCasedRegionTag(region.Span()));

  if (region.Length() == 2) {
    return region.EqualTo("AN") ||
           region.EqualTo("NT") ||
           region.EqualTo("PC") ||
           region.EqualTo("SU");
  }

  {
    static const char regions[8][4] = {
      "172", "200", "530", "532", "536", "582", "810", "890",
    };

    return HasReplacement(regions, region);
  }
}

// Language subtags with complex mappings.
// Derived from CLDR Supplemental Data, version 48.2.
// https://unicode.org/Public/cldr/48.2/cldr-common-48.2.zip
void mozilla::intl::Locale::PerformComplexLanguageMappings() {
  MOZ_ASSERT(IsStructurallyValidLanguageTag(Language().Span()));
  MOZ_ASSERT(IsCanonicallyCasedLanguageTag(Language().Span()));

  if (Language().EqualTo("cnr")) {
    SetLanguage("sr");
    if (Region().Missing()) {
      SetRegion("ME");
    }
  }
  else if (Language().EqualTo("drw") ||
           Language().EqualTo("prs") ||
           Language().EqualTo("tnf")) {
    SetLanguage("fa");
    if (Region().Missing()) {
      SetRegion("AF");
    }
  }
  else if (Language().EqualTo("hbs") ||
           Language().EqualTo("sh")) {
    SetLanguage("sr");
    if (Script().Missing()) {
      SetScript("Latn");
    }
  }
  else if (Language().EqualTo("swc")) {
    SetLanguage("sw");
    if (Region().Missing()) {
      SetRegion("CD");
    }
  }
}

// Region subtags with complex mappings.
// Derived from CLDR Supplemental Data, version 48.2.
// https://unicode.org/Public/cldr/48.2/cldr-common-48.2.zip
void mozilla::intl::Locale::PerformComplexRegionMappings() {
  MOZ_ASSERT(IsStructurallyValidLanguageTag(Language().Span()));
  MOZ_ASSERT(IsCanonicallyCasedLanguageTag(Language().Span()));
  MOZ_ASSERT(IsStructurallyValidRegionTag(Region().Span()));
  MOZ_ASSERT(IsCanonicallyCasedRegionTag(Region().Span()));

  if (Region().EqualTo("172")) {
    if (Language().EqualTo("axm") ||
        Language().EqualTo("hy") ||
        Language().EqualTo("hyw") ||
        (Language().EqualTo("ku") && Script().EqualTo("Cyrl")) ||
        Language().EqualTo("rmi") ||
        (Language().EqualTo("und") && Script().EqualTo("Armn"))) {
      SetRegion("AM");
    }
    else if (Language().EqualTo("az") ||
             Language().EqualTo("bdk") ||
             Language().EqualTo("kjj") ||
             Language().EqualTo("kry") ||
             Language().EqualTo("tkr") ||
             Language().EqualTo("tly") ||
             Language().EqualTo("ttt") ||
             (Language().EqualTo("und") && Script().EqualTo("Aghb")) ||
             Language().EqualTo("xag")) {
      SetRegion("AZ");
    }
    else if (Language().EqualTo("be")) {
      SetRegion("BY");
    }
    else if (Language().EqualTo("ab") ||
             Language().EqualTo("bbl") ||
             Language().EqualTo("bhn") ||
             Language().EqualTo("jge") ||
             Language().EqualTo("ka") ||
             (Language().EqualTo("ku") && Script().EqualTo("Yezi")) ||
             (Language().EqualTo("lzz") && Script().EqualTo("Geor")) ||
             Language().EqualTo("oav") ||
             Language().EqualTo("os") ||
             Language().EqualTo("sva") ||
             (Language().EqualTo("und") && Script().EqualTo("Geor")) ||
             (Language().EqualTo("und") && Script().EqualTo("Yezi")) ||
             Language().EqualTo("uum") ||
             Language().EqualTo("xmf")) {
      SetRegion("GE");
    }
    else if (Language().EqualTo("dng") ||
             Language().EqualTo("ky")) {
      SetRegion("KG");
    }
    else if (Language().EqualTo("kk") ||
             (Language().EqualTo("ug") && Script().EqualTo("Cyrl"))) {
      SetRegion("KZ");
    }
    else if (Language().EqualTo("gag")) {
      SetRegion("MD");
    }
    else if (Language().EqualTo("abh") ||
             Language().EqualTo("paq") ||
             Language().EqualTo("sgh") ||
             Language().EqualTo("tg") ||
             Language().EqualTo("yah") ||
             Language().EqualTo("yai")) {
      SetRegion("TJ");
    }
    else if (Language().EqualTo("chg") ||
             Language().EqualTo("tk")) {
      SetRegion("TM");
    }
    else if (Language().EqualTo("crh") ||
             Language().EqualTo("got") ||
             Language().EqualTo("jct") ||
             Language().EqualTo("ji") ||
             Language().EqualTo("rue") ||
             Language().EqualTo("uk") ||
             (Language().EqualTo("und") && Script().EqualTo("Goth")) ||
             Language().EqualTo("yi")) {
      SetRegion("UA");
    }
    else if (Language().EqualTo("auz") ||
             Language().EqualTo("kaa") ||
             Language().EqualTo("sog") ||
             (Language().EqualTo("und") && Script().EqualTo("Chrs")) ||
             (Language().EqualTo("und") && Script().EqualTo("Sogd")) ||
             (Language().EqualTo("und") && Script().EqualTo("Sogo")) ||
             Language().EqualTo("uz") ||
             Language().EqualTo("xco")) {
      SetRegion("UZ");
    }
    else {
      SetRegion("RU");
    }
  }
  else if (Region().EqualTo("200")) {
    if (Language().EqualTo("rmc") ||
        Language().EqualTo("sk")) {
      SetRegion("SK");
    }
    else {
      SetRegion("CZ");
    }
  }
  else if (Region().EqualTo("530") ||
           Region().EqualTo("532") ||
           Region().EqualTo("AN")) {
    if (Language().EqualTo("vic")) {
      SetRegion("SX");
    }
    else {
      SetRegion("CW");
    }
  }
  else if (Region().EqualTo("536") ||
           Region().EqualTo("NT")) {
    if (Language().EqualTo("acm") ||
        Language().EqualTo("aii") ||
        Language().EqualTo("akk") ||
        (Language().EqualTo("arc") && Script().EqualTo("Hatr")) ||
        Language().EqualTo("ayp") ||
        Language().EqualTo("bjm") ||
        Language().EqualTo("ckb") ||
        Language().EqualTo("kqd") ||
        (Language().EqualTo("ku") && Script().EqualTo("Arab")) ||
        Language().EqualTo("mid") ||
        Language().EqualTo("sdb") ||
        Language().EqualTo("sdf") ||
        Language().EqualTo("syr") ||
        (Language().EqualTo("und") && Script().EqualTo("Hatr")) ||
        (Language().EqualTo("und") && Script().EqualTo("Syrc")) ||
        (Language().EqualTo("und") && Script().EqualTo("Xsux"))) {
      SetRegion("IQ");
    }
    else {
      SetRegion("SA");
    }
  }
  else if (Region().EqualTo("582") ||
           Region().EqualTo("PC")) {
    if (Language().EqualTo("mh")) {
      SetRegion("MH");
    }
    else if (Language().EqualTo("cal") ||
             Language().EqualTo("tpv")) {
      SetRegion("MP");
    }
    else if (Language().EqualTo("pau") ||
             Language().EqualTo("sov") ||
             Language().EqualTo("tox")) {
      SetRegion("PW");
    }
    else {
      SetRegion("FM");
    }
  }
  else if (Region().EqualTo("810") ||
           Region().EqualTo("SU")) {
    if (Language().EqualTo("axm") ||
        Language().EqualTo("hy") ||
        Language().EqualTo("hyw") ||
        (Language().EqualTo("ku") && Script().EqualTo("Cyrl")) ||
        Language().EqualTo("rmi") ||
        (Language().EqualTo("und") && Script().EqualTo("Armn"))) {
      SetRegion("AM");
    }
    else if (Language().EqualTo("az") ||
             Language().EqualTo("bdk") ||
             Language().EqualTo("kjj") ||
             Language().EqualTo("kry") ||
             Language().EqualTo("tkr") ||
             Language().EqualTo("tly") ||
             Language().EqualTo("ttt") ||
             (Language().EqualTo("und") && Script().EqualTo("Aghb")) ||
             Language().EqualTo("xag")) {
      SetRegion("AZ");
    }
    else if (Language().EqualTo("be")) {
      SetRegion("BY");
    }
    else if (Language().EqualTo("et") ||
             Language().EqualTo("ie") ||
             Language().EqualTo("vro")) {
      SetRegion("EE");
    }
    else if (Language().EqualTo("ab") ||
             Language().EqualTo("bbl") ||
             Language().EqualTo("bhn") ||
             Language().EqualTo("jge") ||
             Language().EqualTo("ka") ||
             (Language().EqualTo("ku") && Script().EqualTo("Yezi")) ||
             (Language().EqualTo("lzz") && Script().EqualTo("Geor")) ||
             Language().EqualTo("oav") ||
             Language().EqualTo("os") ||
             Language().EqualTo("sva") ||
             (Language().EqualTo("und") && Script().EqualTo("Geor")) ||
             (Language().EqualTo("und") && Script().EqualTo("Yezi")) ||
             Language().EqualTo("uum") ||
             Language().EqualTo("xmf")) {
      SetRegion("GE");
    }
    else if (Language().EqualTo("dng") ||
             Language().EqualTo("ky")) {
      SetRegion("KG");
    }
    else if (Language().EqualTo("kk") ||
             (Language().EqualTo("ug") && Script().EqualTo("Cyrl"))) {
      SetRegion("KZ");
    }
    else if (Language().EqualTo("kdr") ||
             Language().EqualTo("lt") ||
             Language().EqualTo("olt") ||
             Language().EqualTo("sgs")) {
      SetRegion("LT");
    }
    else if (Language().EqualTo("liv") ||
             Language().EqualTo("ltg") ||
             Language().EqualTo("lv")) {
      SetRegion("LV");
    }
    else if (Language().EqualTo("gag")) {
      SetRegion("MD");
    }
    else if (Language().EqualTo("abh") ||
             Language().EqualTo("paq") ||
             Language().EqualTo("sgh") ||
             Language().EqualTo("tg") ||
             Language().EqualTo("yah") ||
             Language().EqualTo("yai")) {
      SetRegion("TJ");
    }
    else if (Language().EqualTo("chg") ||
             Language().EqualTo("tk")) {
      SetRegion("TM");
    }
    else if (Language().EqualTo("crh") ||
             Language().EqualTo("got") ||
             Language().EqualTo("jct") ||
             Language().EqualTo("ji") ||
             Language().EqualTo("rue") ||
             Language().EqualTo("uk") ||
             (Language().EqualTo("und") && Script().EqualTo("Goth")) ||
             Language().EqualTo("yi")) {
      SetRegion("UA");
    }
    else if (Language().EqualTo("auz") ||
             Language().EqualTo("kaa") ||
             Language().EqualTo("sog") ||
             (Language().EqualTo("und") && Script().EqualTo("Chrs")) ||
             (Language().EqualTo("und") && Script().EqualTo("Sogd")) ||
             (Language().EqualTo("und") && Script().EqualTo("Sogo")) ||
             Language().EqualTo("uz") ||
             Language().EqualTo("xco")) {
      SetRegion("UZ");
    }
    else {
      SetRegion("RU");
    }
  }
  else if (Region().EqualTo("890")) {
    if (Language().EqualTo("bs")) {
      SetRegion("BA");
    }
    else if (Language().EqualTo("ckm") ||
             Language().EqualTo("dlm") ||
             Language().EqualTo("hr") ||
             Language().EqualTo("ist") ||
             Language().EqualTo("ruo")) {
      SetRegion("HR");
    }
    else if (Language().EqualTo("mk")) {
      SetRegion("MK");
    }
    else if (Language().EqualTo("sl")) {
      SetRegion("SI");
    }
    else {
      SetRegion("RS");
    }
  }
}

static auto ToSpan(const mozilla::Span<const char>& aSpan) {
  return aSpan;
}

template <size_t N>
static auto ToSpan(const mozilla::intl::LanguageTagSubtag<N>& aSubtag) {
  return aSubtag.Span();
}

template <typename T, typename U = T>
static bool IsLessThan(const T& a, const U& b) {
  return ToSpan(a) < ToSpan(b);
}

// Mappings from variant subtags to preferred values.
// Derived from CLDR Supplemental Data, version 48.2.
// https://unicode.org/Public/cldr/48.2/cldr-common-48.2.zip
bool mozilla::intl::Locale::PerformVariantMappings() {
  // The variant subtags need to be sorted for binary search.
  MOZ_ASSERT(std::is_sorted(mVariants.begin(), mVariants.end(),
                            IsLessThan<decltype(mVariants)::ElementType>));

  auto removeVariantAt = [&](size_t index) {
    mVariants.erase(mVariants.begin() + index);
  };

  auto insertVariantSortedIfNotPresent = [&](mozilla::Span<const char> variant) {
    auto* p = std::lower_bound(
        mVariants.begin(), mVariants.end(), variant,
        IsLessThan<decltype(mVariants)::ElementType, decltype(variant)>);

    // Don't insert the replacement when already present.
    if (p != mVariants.end() && p->Span() == variant) {
      return true;
    }

    // Insert the preferred variant in sort order.
    auto preferred = mozilla::intl::VariantSubtag{variant};
    return !!mVariants.insert(p, preferred);
  };

  for (size_t i = 0; i < mVariants.length();) {
    const auto& variant = mVariants[i];
    MOZ_ASSERT(IsCanonicallyCasedVariantTag(variant.Span()));

    if (variant.Span() == mozilla::MakeStringSpan("arevela") ||
        variant.Span() == mozilla::MakeStringSpan("arevmda") ||
        variant.Span() == mozilla::MakeStringSpan("bokmal") ||
        variant.Span() == mozilla::MakeStringSpan("hakka") ||
        variant.Span() == mozilla::MakeStringSpan("lojban") ||
        variant.Span() == mozilla::MakeStringSpan("nynorsk") ||
        variant.Span() == mozilla::MakeStringSpan("saaho") ||
        variant.Span() == mozilla::MakeStringSpan("xiang")) {
      removeVariantAt(i);
    }
    else if (variant.Span() == mozilla::MakeStringSpan("aaland")) {
      removeVariantAt(i);
      SetRegion("AX");
    }
    else if (variant.Span() == mozilla::MakeStringSpan("heploc")) {
      removeVariantAt(i);
      if (!insertVariantSortedIfNotPresent(mozilla::MakeStringSpan("alalc97"))) {
        return false;
      }
    }
    else if (variant.Span() == mozilla::MakeStringSpan("polytoni")) {
      removeVariantAt(i);
      if (!insertVariantSortedIfNotPresent(mozilla::MakeStringSpan("polyton"))) {
        return false;
      }
    }
    else {
      i++;
    }
  }
  return true;
}

// Canonicalize legacy locale identifiers.
// Derived from CLDR Supplemental Data, version 48.2.
// https://unicode.org/Public/cldr/48.2/cldr-common-48.2.zip
bool mozilla::intl::Locale::UpdateLegacyMappings() {
  // We're mapping legacy tags to non-legacy form here.
  // Other tags remain unchanged.
  //
  // Legacy tags are either sign language tags ("sgn") or have one or multiple
  // variant subtags. Therefore we can quickly exclude most tags by checking
  // these two subtags.

  MOZ_ASSERT(IsCanonicallyCasedLanguageTag(Language().Span()));

  if (!Language().EqualTo("sgn") && mVariants.length() == 0) {
    return true;
  }

#ifdef DEBUG
  for (const auto& variant : Variants()) {
    MOZ_ASSERT(IsStructurallyValidVariantTag(variant));
    MOZ_ASSERT(IsCanonicallyCasedVariantTag(variant));
  }
#endif

  // The variant subtags need to be sorted for binary search.
  MOZ_ASSERT(std::is_sorted(mVariants.begin(), mVariants.end(),
                            IsLessThan<decltype(mVariants)::ElementType>));

  auto findVariant = [this](mozilla::Span<const char> variant) {
    auto* p = std::lower_bound(mVariants.begin(), mVariants.end(), variant,
                               IsLessThan<decltype(mVariants)::ElementType,
                                          decltype(variant)>);

    if (p != mVariants.end() && p->Span() == variant) {
      return p;
    }
    return static_cast<decltype(p)>(nullptr);
  };

  auto insertVariantSortedIfNotPresent = [&](mozilla::Span<const char> variant) {
    auto* p = std::lower_bound(mVariants.begin(), mVariants.end(), variant,
                               IsLessThan<decltype(mVariants)::ElementType,
                                          decltype(variant)>);

    // Don't insert the replacement when already present.
    if (p != mVariants.end() && p->Span() == variant) {
      return true;
    }

    // Insert the preferred variant in sort order.
    auto preferred = mozilla::intl::VariantSubtag{variant};
    return !!mVariants.insert(p, preferred);
  };

  auto removeVariant = [&](auto* p) {
    size_t index = std::distance(mVariants.begin(), p);
    mVariants.erase(mVariants.begin() + index);
  };

  auto removeVariants = [&](auto* p, auto* q) {
    size_t pIndex = std::distance(mVariants.begin(), p);
    size_t qIndex = std::distance(mVariants.begin(), q);
    MOZ_ASSERT(pIndex < qIndex, "variant subtags are sorted");

    mVariants.erase(mVariants.begin() + qIndex);
    mVariants.erase(mVariants.begin() + pIndex);
  };

  if (mVariants.length() >= 2) {
    if (auto* hepburn = findVariant(mozilla::MakeStringSpan("hepburn"))) {
      if (auto* heploc = findVariant(mozilla::MakeStringSpan("heploc"))) {
        removeVariants(hepburn, heploc);

        if (!insertVariantSortedIfNotPresent(mozilla::MakeStringSpan("alalc97"))) {
          return false;
        }
      }
    }
  }

  if (Language().EqualTo("sgn")) {
    if (Region().Present() && SignLanguageMapping(mLanguage, Region())) {
      mRegion.Set(mozilla::MakeStringSpan(""));
    }
  }
  else if (Language().EqualTo("aa") ||
           Language().EqualTo("aar")) {
    if (auto* saaho = findVariant(mozilla::MakeStringSpan("saaho"))) {
      removeVariant(saaho);
      SetLanguage("ssy");
    }
  }
  else if (Language().EqualTo("arm") ||
           Language().EqualTo("hy") ||
           Language().EqualTo("hye")) {
    if (auto* arevmda = findVariant(mozilla::MakeStringSpan("arevmda"))) {
      removeVariant(arevmda);
      SetLanguage("hyw");
    }
  }
  else if (Language().EqualTo("art")) {
    if (auto* lojban = findVariant(mozilla::MakeStringSpan("lojban"))) {
      removeVariant(lojban);
      SetLanguage("jbo");
    }
  }
  else if (Language().EqualTo("cel")) {
    if (auto* gaulish = findVariant(mozilla::MakeStringSpan("gaulish"))) {
      removeVariant(gaulish);
      SetLanguage("xtg");
    }
  }
  else if (Language().EqualTo("chi") ||
           Language().EqualTo("cmn") ||
           Language().EqualTo("zh") ||
           Language().EqualTo("zho")) {
    if (auto* guoyu = findVariant(mozilla::MakeStringSpan("guoyu"))) {
      if (auto* hakka = findVariant(mozilla::MakeStringSpan("hakka"))) {
        removeVariants(guoyu, hakka);
        SetLanguage("hak");
        return true;
      }
    }
    if (auto* guoyu = findVariant(mozilla::MakeStringSpan("guoyu"))) {
      if (auto* xiang = findVariant(mozilla::MakeStringSpan("xiang"))) {
        removeVariants(guoyu, xiang);
        SetLanguage("hsn");
        return true;
      }
    }
    if (auto* guoyu = findVariant(mozilla::MakeStringSpan("guoyu"))) {
      removeVariant(guoyu);
      SetLanguage("zh");
    }
    else if (auto* hakka = findVariant(mozilla::MakeStringSpan("hakka"))) {
      removeVariant(hakka);
      SetLanguage("hak");
    }
    else if (auto* xiang = findVariant(mozilla::MakeStringSpan("xiang"))) {
      removeVariant(xiang);
      SetLanguage("hsn");
    }
  }
  else if (Language().EqualTo("no") ||
           Language().EqualTo("nor")) {
    if (auto* bokmal = findVariant(mozilla::MakeStringSpan("bokmal"))) {
      removeVariant(bokmal);
      SetLanguage("nb");
    }
    else if (auto* nynorsk = findVariant(mozilla::MakeStringSpan("nynorsk"))) {
      removeVariant(nynorsk);
      SetLanguage("nn");
    }
  }

  return true;
}

// Mappings from legacy sign languages.
// Derived from CLDR Supplemental Data, version 48.2.
// https://unicode.org/Public/cldr/48.2/cldr-common-48.2.zip
bool mozilla::intl::Locale::SignLanguageMapping(LanguageSubtag& language,
                                                const RegionSubtag& region) {
  MOZ_ASSERT(language.EqualTo("sgn"));
  MOZ_ASSERT(IsStructurallyValidRegionTag(region.Span()));
  MOZ_ASSERT(IsCanonicallyCasedRegionTag(region.Span()));

  if (region.Length() == 2) {
    static const char regions[22][3] = {
      "BR", "CO", "DD", "DE", "DK", "ES", "FR", "FX", "GB", "GR",
      "IE", "IT", "JP", "MX", "NI", "NL", "NO", "PT", "SE", "UK",
      "US", "ZA",
    };
    static const char* aliases[22] = {
      "bzs", "csn", "gsg", "gsg", "dsl", "ssp", "fsl", "fsl", "bfi", "gss",
      "isg", "ise", "jsl", "mfs", "ncs", "dse", "nsi", "psr", "swl", "bfi",
      "ase", "sfs",
    };

    if (const char* replacement = SearchReplacement(regions, aliases, region)) {
      language.Set(mozilla::MakeStringSpan(replacement));
      return true;
    }
    return false;
  }

  {
    static const char regions[22][4] = {
      "076", "170", "208", "249", "250", "276", "278", "280", "300", "372",
      "380", "392", "484", "528", "558", "578", "620", "710", "724", "752",
      "826", "840",
    };
    static const char* aliases[22] = {
      "bzs", "csn", "dsl", "fsl", "fsl", "gsg", "gsg", "gsg", "gss", "isg",
      "ise", "jsl", "mfs", "dse", "ncs", "nsi", "psr", "sfs", "ssp", "swl",
      "bfi", "ase",
    };

    if (const char* replacement = SearchReplacement(regions, aliases, region)) {
      language.Set(mozilla::MakeStringSpan(replacement));
      return true;
    }
    return false;
  }
}

template <size_t Length>
static inline bool IsUnicodeKey(mozilla::Span<const char> key, const char (&str)[Length]) {
  static_assert(Length == UnicodeKeyLength + 1,
                "Unicode extension key is two characters long");
  return memcmp(key.data(), str, Length - 1) == 0;
}

template <size_t Length>
static inline bool IsUnicodeType(mozilla::Span<const char> type, const char (&str)[Length]) {
  static_assert(Length > UnicodeKeyLength + 1,
                "Unicode extension type contains more than two characters");
  return type.size() == (Length - 1) &&
         memcmp(type.data(), str, Length - 1) == 0;
}

static int32_t CompareUnicodeType(const char* a, mozilla::Span<const char> b) {
  MOZ_ASSERT(!std::char_traits<char>::find(b.data(), b.size(), '\0'),
             "unexpected null-character in string");

  using UnsignedChar = unsigned char;
  for (size_t i = 0; i < b.size(); i++) {
    // |a| is zero-terminated and |b| doesn't contain a null-terminator. So if
    // we've reached the end of |a|, the below if-statement will always be true.
    // That ensures we don't read past the end of |a|.
    if (int32_t r = UnsignedChar(a[i]) - UnsignedChar(b[i])) {
      return r;
    }
  }

  // Return zero if both strings are equal or a positive number if |b| is a
  // prefix of |a|.
  return int32_t(UnsignedChar(a[b.size()]));
}

template <size_t Length>
static inline const char* SearchUnicodeReplacement(
  const char* (&types)[Length], const char* (&aliases)[Length],
  mozilla::Span<const char> type) {

  auto p = std::lower_bound(std::begin(types), std::end(types), type,
                            [](const auto& a, const auto& b) {
                              return CompareUnicodeType(a, b) < 0;
                            });
  if (p != std::end(types) && CompareUnicodeType(*p, type) == 0) {
    return aliases[std::distance(std::begin(types), p)];
  }
  return nullptr;
}

/**
 * Mapping from deprecated BCP 47 Unicode extension types to their preferred
 * values.
 *
 * Spec: https://www.unicode.org/reports/tr35/#Unicode_Locale_Extension_Data_Files
 * Spec: https://www.unicode.org/reports/tr35/#t_Extension
 */
const char* mozilla::intl::Locale::ReplaceUnicodeExtensionType(
    mozilla::Span<const char> key, mozilla::Span<const char> type) {
  MOZ_ASSERT(key.size() == UnicodeKeyLength);
  MOZ_ASSERT(IsCanonicallyCasedUnicodeKey(key));

  MOZ_ASSERT(type.size() > UnicodeKeyLength);
  MOZ_ASSERT(IsCanonicallyCasedUnicodeType(type));

  if (IsUnicodeKey(key, "ca")) {
    if (IsUnicodeType(type, "ethiopic-amete-alem")) {
      return "ethioaa";
    }
    if (IsUnicodeType(type, "islamicc")) {
      return "islamic-civil";
    }
  }
  else if (IsUnicodeKey(key, "kb") ||
           IsUnicodeKey(key, "kc") ||
           IsUnicodeKey(key, "kh") ||
           IsUnicodeKey(key, "kk") ||
           IsUnicodeKey(key, "kn")) {
    if (IsUnicodeType(type, "yes")) {
      return "true";
    }
  }
  else if (IsUnicodeKey(key, "ks")) {
    if (IsUnicodeType(type, "primary")) {
      return "level1";
    }
    if (IsUnicodeType(type, "tertiary")) {
      return "level3";
    }
  }
  else if (IsUnicodeKey(key, "ms")) {
    if (IsUnicodeType(type, "imperial")) {
      return "uksystem";
    }
  }
  else if (IsUnicodeKey(key, "rg") ||
           IsUnicodeKey(key, "sd")) {
    static const char* types[147] = {
         "cn11" ,  "cn12" ,  "cn13" ,  "cn14" ,  "cn15" ,  "cn21" ,  "cn22" ,
         "cn23" ,  "cn31" ,  "cn32" ,  "cn33" ,  "cn34" ,  "cn35" ,  "cn36" ,
         "cn37" ,  "cn41" ,  "cn42" ,  "cn43" ,  "cn44" ,  "cn45" ,  "cn46" ,
         "cn50" ,  "cn51" ,  "cn52" ,  "cn53" ,  "cn54" ,  "cn61" ,  "cn62" ,
         "cn63" ,  "cn64" ,  "cn65" ,  "cn71" ,  "cn91" ,  "cn92" , "cz10a" ,
        "cz10b" , "cz10c" , "cz10d" , "cz10e" , "cz10f" , "cz611" , "cz612" ,
        "cz613" , "cz614" , "cz615" , "cz621" , "cz622" , "cz623" , "cz624" ,
        "cz626" , "cz627" ,  "czjc" ,  "czjm" ,  "czka" ,  "czkr" ,  "czli" ,
         "czmo" ,  "czol" ,  "czpa" ,  "czpl" ,  "czpr" ,  "czst" ,  "czus" ,
         "czvy" ,  "czzl" ,  "fi01" ,  "fra"  ,  "frb"  ,  "frbl" ,  "frc"  ,
         "frcp" ,  "frd"  ,  "fre"  ,  "frf"  ,  "frg"  ,  "frgf" ,  "frgp" ,
        "frgua" ,  "frh"  ,  "fri"  ,  "frj"  ,  "frk"  ,  "frl"  , "frlre" ,
         "frm"  , "frmay" ,  "frmf" ,  "frmq" ,  "frn"  ,  "frnc" ,  "fro"  ,
         "frp"  ,  "frpf" ,  "frpm" ,  "frq"  ,  "frr"  ,  "frre" ,  "frs"  ,
         "frt"  ,  "frtf" ,  "fru"  ,  "frv"  ,  "frwf" ,  "fryt" ,  "laxn" ,
         "lud"  ,  "lug"  ,  "lul"  , "mrnkc" ,  "nlaw" ,  "nlcw" ,  "nlsx" ,
         "no23" ,  "nzn"  ,  "nzs"  ,  "omba" ,  "omsh" ,  "plds" ,  "plkp" ,
         "pllb" ,  "plld" ,  "pllu" ,  "plma" ,  "plmz" ,  "plop" ,  "plpd" ,
         "plpk" ,  "plpm" ,  "plsk" ,  "plsl" ,  "plwn" ,  "plwp" ,  "plzp" ,
         "shta" , "tteto" , "ttrcm" , "ttwto" , "twkhq" , "twtnq" , "twtpq" ,
        "twtxq" ,  "usas" ,  "usgu" ,  "usmp" ,  "uspr" ,  "usum" ,  "usvi" ,
    };
    static const char* aliases[147] = {
         "cnbj" ,  "cntj" ,  "cnhe" ,  "cnsx" ,  "cnmn" ,  "cnln" ,  "cnjl" ,
         "cnhl" ,  "cnsh" ,  "cnjs" ,  "cnzj" ,  "cnah" ,  "cnfj" ,  "cnjx" ,
         "cnsd" ,  "cnha" ,  "cnhb" ,  "cnhn" ,  "cngd" ,  "cngx" ,  "cnhi" ,
         "cncq" ,  "cnsc" ,  "cngz" ,  "cnyn" ,  "cnxz" ,  "cnsn" ,  "cngs" ,
         "cnqh" ,  "cnnx" ,  "cnxj" , "twzzzz", "hkzzzz", "mozzzz", "cz110" ,
        "cz111" , "cz112" , "cz113" , "cz114" , "cz115" , "cz663" , "cz632" ,
        "cz633" , "cz634" , "cz635" , "cz641" , "cz642" , "cz643" , "cz644" ,
        "cz646" , "cz647" ,  "cz31" ,  "cz64" ,  "cz41" ,  "cz52" ,  "cz51" ,
         "cz80" ,  "cz71" ,  "cz53" ,  "cz32" ,  "cz10" ,  "cz20" ,  "cz42" ,
         "cz63" ,  "cz72" , "axzzzz", "frges" , "frnaq" , "blzzzz", "frara" ,
        "cpzzzz", "frbfc" , "frbre" , "frcvl" , "frges" , "gfzzzz", "gpzzzz",
        "gpzzzz", "frcor" , "frbfc" , "fridf" , "frocc" , "frnaq" , "rezzzz",
        "frges" , "ytzzzz", "mfzzzz", "mqzzzz", "frocc" , "nczzzz", "frhdf" ,
        "frnor" , "pfzzzz", "pmzzzz", "frnor" , "frpdl" , "rezzzz", "frhdf" ,
        "frnaq" , "tfzzzz", "frpac" , "frara" , "wfzzzz", "ytzzzz",  "laxs" ,
         "lucl" ,  "luec" ,  "luca" ,  "mr13" , "awzzzz", "cwzzzz", "sxzzzz",
         "no50" , "nzauk" , "nzcan" ,  "ombj" ,  "omsj" ,  "pl02" ,  "pl04" ,
         "pl08" ,  "pl10" ,  "pl06" ,  "pl12" ,  "pl14" ,  "pl16" ,  "pl20" ,
         "pl18" ,  "pl22" ,  "pl26" ,  "pl24" ,  "pl28" ,  "pl30" ,  "pl32" ,
        "tazzzz", "tttob" , "ttmrc" , "tttob" , "twkhh" , "twtnn" , "twnwt" ,
        "twtxg" , "aszzzz", "guzzzz", "mpzzzz", "przzzz", "umzzzz", "vizzzz",
    };
    return SearchUnicodeReplacement(types, aliases, type);
  }
  else if (IsUnicodeKey(key, "tz")) {
    static const char* types[50] = {
         "aqams"  ,  "aukns"  ,  "caffs"  ,  "camtr"  ,  "canpg"  ,  "capnt"  ,
         "cathu"  ,  "cayzf"  ,   "cet"   ,  "cnckg"  ,  "cnhrb"  ,  "cnkhg"  ,
        "cst6cdt" ,   "cuba"  ,   "eet"   ,  "egypt"  ,   "eire"  ,   "est"   ,
        "est5edt" , "factory" ,   "gaza"  ,   "gmt0"  , "hongkong",   "hst"   ,
        "iceland" ,   "iran"  ,  "israel" , "jamaica" ,  "japan"  ,  "libya"  ,
          "met"   ,  "mncoq"  ,   "mst"   , "mst7mdt" ,  "mxstis" ,  "navajo" ,
         "poland" , "portugal",   "prc"   , "pst8pdt" ,   "roc"   ,   "rok"   ,
         "turkey" ,  "uaozh"  ,  "uauzh"  ,   "uct"   ,  "umjon"  , "usnavajo",
          "wet"   ,   "zulu"  ,
    };
    static const char* aliases[50] = {
         "aqmcm"  ,  "auhba"  ,  "cawnp"  ,  "cator"  ,  "cator"  ,  "caiql"  ,
         "cator"  ,  "caedm"  ,  "bebru"  ,  "cnsha"  ,  "cnsha"  ,  "cnurc"  ,
         "uschi"  ,  "cuhav"  ,  "grath"  ,  "egcai"  ,  "iedub"  ,  "papty"  ,
         "usnyc"  ,   "unk"   , "gazastrp",   "gmt"   ,  "hkhkg"  ,  "ushnl"  ,
         "isrey"  ,  "irthr"  , "jeruslm" ,  "jmkin"  ,  "jptyo"  ,  "lytip"  ,
         "bebru"  ,  "mnuln"  ,  "usphx"  ,  "usden"  ,  "mxtij"  ,  "usden"  ,
         "plwaw"  ,  "ptlis"  ,  "cnsha"  ,  "uslax"  ,  "twtpe"  ,  "krsel"  ,
         "trist"  ,  "uaiev"  ,  "uaiev"  ,   "utc"   ,  "ushnl"  ,  "usden"  ,
         "ptlis"  ,   "utc"   ,
    };
    return SearchUnicodeReplacement(types, aliases, type);
  }
  return nullptr;
}

template <size_t Length>
static inline bool IsTransformKey(mozilla::Span<const char> key, const char (&str)[Length]) {
  static_assert(Length == TransformKeyLength + 1,
                "Transform extension key is two characters long");
  return memcmp(key.data(), str, Length - 1) == 0;
}

template <size_t Length>
static inline bool IsTransformType(mozilla::Span<const char> type, const char (&str)[Length]) {
  static_assert(Length > TransformKeyLength + 1,
                "Transform extension type contains more than two characters");
  return type.size() == (Length - 1) &&
         memcmp(type.data(), str, Length - 1) == 0;
}

/**
 * Mapping from deprecated BCP 47 Transform extension types to their preferred
 * values.
 *
 * Spec: https://www.unicode.org/reports/tr35/#Unicode_Locale_Extension_Data_Files
 * Spec: https://www.unicode.org/reports/tr35/#t_Extension
 */
const char* mozilla::intl::Locale::ReplaceTransformExtensionType(
    mozilla::Span<const char> key, mozilla::Span<const char> type) {
  MOZ_ASSERT(key.size() == TransformKeyLength);
  MOZ_ASSERT(IsCanonicallyCasedTransformKey(key));

  MOZ_ASSERT(type.size() > TransformKeyLength);
  MOZ_ASSERT(IsCanonicallyCasedTransformType(type));

  if (IsTransformKey(key, "d0")) {
    if (IsTransformType(type, "name")) {
      return "charname";
    }
  }
  else if (IsTransformKey(key, "m0")) {
    if (IsTransformType(type, "beta-metsehaf")) {
      return "betamets";
    }
    if (IsTransformType(type, "ies-jes")) {
      return "iesjes";
    }
    if (IsTransformType(type, "names")) {
      return "prprname";
    }
    if (IsTransformType(type, "tekie-alibekit")) {
      return "tekieali";
    }
  }
  return nullptr;
}