// index returns the index of the tag for the given base, script and region or
// its parent if the tag is not available. If the match is for a parent entry,
// the excess script and region are returned.
func (ts *tagSet) index(base language.Base, scr language.Script, reg language.Region) (int, language.Script, language.Region) {
lang := base.String()
index := -1
if (scr != language.Script{} || reg != language.Region{}) {
if scr == zzzz {
scr = language.Script{}
}
if reg == zz {
reg = language.Region{}
}
i := sort.SearchStrings(ts.long, lang)
// All entries have either a script or a region and not both.
scrStr, regStr := scr.String(), reg.String()
for ; i < len(ts.long) && strings.HasPrefix(ts.long[i], lang); i++ {
if s := ts.long[i][len(lang)+1:]; s == scrStr {
scr = language.Script{}
index = i + ts.single.len()
break
} else if s == regStr {
reg = language.Region{}
index = i + ts.single.len()
break
}
}
}
if index == -1 {
index = ts.single.index(lang)
}
return index, scr, reg
}
// GetLocale generates a locale from a base and a region and may use an optional script.
// lang
// lang_script
// lang_script_region
// lang_region (aliases to lang_script_region)
func GetLocale(b language.Base, r language.Region, s ...language.Script) string {
ret := b.String()
if len(s) == 1 {
ret += LocaleSeparator + s[0].String()
}
return ret + LocaleSeparator + r.String()
}
// regionToCode returns a 16-bit region code. Only two-letter codes are
// supported. (Three-letter codes are not needed.)
func regionToCode(r language.Region) uint16 {
if s := r.String(); len(s) == 2 {
return uint16(s[0])<<8 | uint16(s[1])
}
return 0
}