mirror of
https://github.com/42wim/matterbridge.git
synced 2024-12-12 20:22:01 -08:00
227 lines
5.7 KiB
Go
227 lines
5.7 KiB
Go
|
// Copyright 2013 The Go Authors. All rights reserved.
|
||
|
// Use of this source code is governed by a BSD-style
|
||
|
// license that can be found in the LICENSE file.
|
||
|
|
||
|
package language
|
||
|
|
||
|
import "errors"
|
||
|
|
||
|
type scriptRegionFlags uint8
|
||
|
|
||
|
const (
|
||
|
isList = 1 << iota
|
||
|
scriptInFrom
|
||
|
regionInFrom
|
||
|
)
|
||
|
|
||
|
func (t *Tag) setUndefinedLang(id Language) {
|
||
|
if t.LangID == 0 {
|
||
|
t.LangID = id
|
||
|
}
|
||
|
}
|
||
|
|
||
|
func (t *Tag) setUndefinedScript(id Script) {
|
||
|
if t.ScriptID == 0 {
|
||
|
t.ScriptID = id
|
||
|
}
|
||
|
}
|
||
|
|
||
|
func (t *Tag) setUndefinedRegion(id Region) {
|
||
|
if t.RegionID == 0 || t.RegionID.Contains(id) {
|
||
|
t.RegionID = id
|
||
|
}
|
||
|
}
|
||
|
|
||
|
// ErrMissingLikelyTagsData indicates no information was available
|
||
|
// to compute likely values of missing tags.
|
||
|
var ErrMissingLikelyTagsData = errors.New("missing likely tags data")
|
||
|
|
||
|
// addLikelySubtags sets subtags to their most likely value, given the locale.
|
||
|
// In most cases this means setting fields for unknown values, but in some
|
||
|
// cases it may alter a value. It returns an ErrMissingLikelyTagsData error
|
||
|
// if the given locale cannot be expanded.
|
||
|
func (t Tag) addLikelySubtags() (Tag, error) {
|
||
|
id, err := addTags(t)
|
||
|
if err != nil {
|
||
|
return t, err
|
||
|
} else if id.equalTags(t) {
|
||
|
return t, nil
|
||
|
}
|
||
|
id.RemakeString()
|
||
|
return id, nil
|
||
|
}
|
||
|
|
||
|
// specializeRegion attempts to specialize a group region.
|
||
|
func specializeRegion(t *Tag) bool {
|
||
|
if i := regionInclusion[t.RegionID]; i < nRegionGroups {
|
||
|
x := likelyRegionGroup[i]
|
||
|
if Language(x.lang) == t.LangID && Script(x.script) == t.ScriptID {
|
||
|
t.RegionID = Region(x.region)
|
||
|
}
|
||
|
return true
|
||
|
}
|
||
|
return false
|
||
|
}
|
||
|
|
||
|
// Maximize returns a new tag with missing tags filled in.
|
||
|
func (t Tag) Maximize() (Tag, error) {
|
||
|
return addTags(t)
|
||
|
}
|
||
|
|
||
|
func addTags(t Tag) (Tag, error) {
|
||
|
// We leave private use identifiers alone.
|
||
|
if t.IsPrivateUse() {
|
||
|
return t, nil
|
||
|
}
|
||
|
if t.ScriptID != 0 && t.RegionID != 0 {
|
||
|
if t.LangID != 0 {
|
||
|
// already fully specified
|
||
|
specializeRegion(&t)
|
||
|
return t, nil
|
||
|
}
|
||
|
// Search matches for und-script-region. Note that for these cases
|
||
|
// region will never be a group so there is no need to check for this.
|
||
|
list := likelyRegion[t.RegionID : t.RegionID+1]
|
||
|
if x := list[0]; x.flags&isList != 0 {
|
||
|
list = likelyRegionList[x.lang : x.lang+uint16(x.script)]
|
||
|
}
|
||
|
for _, x := range list {
|
||
|
// Deviating from the spec. See match_test.go for details.
|
||
|
if Script(x.script) == t.ScriptID {
|
||
|
t.setUndefinedLang(Language(x.lang))
|
||
|
return t, nil
|
||
|
}
|
||
|
}
|
||
|
}
|
||
|
if t.LangID != 0 {
|
||
|
// Search matches for lang-script and lang-region, where lang != und.
|
||
|
if t.LangID < langNoIndexOffset {
|
||
|
x := likelyLang[t.LangID]
|
||
|
if x.flags&isList != 0 {
|
||
|
list := likelyLangList[x.region : x.region+uint16(x.script)]
|
||
|
if t.ScriptID != 0 {
|
||
|
for _, x := range list {
|
||
|
if Script(x.script) == t.ScriptID && x.flags&scriptInFrom != 0 {
|
||
|
t.setUndefinedRegion(Region(x.region))
|
||
|
return t, nil
|
||
|
}
|
||
|
}
|
||
|
} else if t.RegionID != 0 {
|
||
|
count := 0
|
||
|
goodScript := true
|
||
|
tt := t
|
||
|
for _, x := range list {
|
||
|
// We visit all entries for which the script was not
|
||
|
// defined, including the ones where the region was not
|
||
|
// defined. This allows for proper disambiguation within
|
||
|
// regions.
|
||
|
if x.flags&scriptInFrom == 0 && t.RegionID.Contains(Region(x.region)) {
|
||
|
tt.RegionID = Region(x.region)
|
||
|
tt.setUndefinedScript(Script(x.script))
|
||
|
goodScript = goodScript && tt.ScriptID == Script(x.script)
|
||
|
count++
|
||
|
}
|
||
|
}
|
||
|
if count == 1 {
|
||
|
return tt, nil
|
||
|
}
|
||
|
// Even if we fail to find a unique Region, we might have
|
||
|
// an unambiguous script.
|
||
|
if goodScript {
|
||
|
t.ScriptID = tt.ScriptID
|
||
|
}
|
||
|
}
|
||
|
}
|
||
|
}
|
||
|
} else {
|
||
|
// Search matches for und-script.
|
||
|
if t.ScriptID != 0 {
|
||
|
x := likelyScript[t.ScriptID]
|
||
|
if x.region != 0 {
|
||
|
t.setUndefinedRegion(Region(x.region))
|
||
|
t.setUndefinedLang(Language(x.lang))
|
||
|
return t, nil
|
||
|
}
|
||
|
}
|
||
|
// Search matches for und-region. If und-script-region exists, it would
|
||
|
// have been found earlier.
|
||
|
if t.RegionID != 0 {
|
||
|
if i := regionInclusion[t.RegionID]; i < nRegionGroups {
|
||
|
x := likelyRegionGroup[i]
|
||
|
if x.region != 0 {
|
||
|
t.setUndefinedLang(Language(x.lang))
|
||
|
t.setUndefinedScript(Script(x.script))
|
||
|
t.RegionID = Region(x.region)
|
||
|
}
|
||
|
} else {
|
||
|
x := likelyRegion[t.RegionID]
|
||
|
if x.flags&isList != 0 {
|
||
|
x = likelyRegionList[x.lang]
|
||
|
}
|
||
|
if x.script != 0 && x.flags != scriptInFrom {
|
||
|
t.setUndefinedLang(Language(x.lang))
|
||
|
t.setUndefinedScript(Script(x.script))
|
||
|
return t, nil
|
||
|
}
|
||
|
}
|
||
|
}
|
||
|
}
|
||
|
|
||
|
// Search matches for lang.
|
||
|
if t.LangID < langNoIndexOffset {
|
||
|
x := likelyLang[t.LangID]
|
||
|
if x.flags&isList != 0 {
|
||
|
x = likelyLangList[x.region]
|
||
|
}
|
||
|
if x.region != 0 {
|
||
|
t.setUndefinedScript(Script(x.script))
|
||
|
t.setUndefinedRegion(Region(x.region))
|
||
|
}
|
||
|
specializeRegion(&t)
|
||
|
if t.LangID == 0 {
|
||
|
t.LangID = _en // default language
|
||
|
}
|
||
|
return t, nil
|
||
|
}
|
||
|
return t, ErrMissingLikelyTagsData
|
||
|
}
|
||
|
|
||
|
func (t *Tag) setTagsFrom(id Tag) {
|
||
|
t.LangID = id.LangID
|
||
|
t.ScriptID = id.ScriptID
|
||
|
t.RegionID = id.RegionID
|
||
|
}
|
||
|
|
||
|
// minimize removes the region or script subtags from t such that
|
||
|
// t.addLikelySubtags() == t.minimize().addLikelySubtags().
|
||
|
func (t Tag) minimize() (Tag, error) {
|
||
|
t, err := minimizeTags(t)
|
||
|
if err != nil {
|
||
|
return t, err
|
||
|
}
|
||
|
t.RemakeString()
|
||
|
return t, nil
|
||
|
}
|
||
|
|
||
|
// minimizeTags mimics the behavior of the ICU 51 C implementation.
|
||
|
func minimizeTags(t Tag) (Tag, error) {
|
||
|
if t.equalTags(Und) {
|
||
|
return t, nil
|
||
|
}
|
||
|
max, err := addTags(t)
|
||
|
if err != nil {
|
||
|
return t, err
|
||
|
}
|
||
|
for _, id := range [...]Tag{
|
||
|
{LangID: t.LangID},
|
||
|
{LangID: t.LangID, RegionID: t.RegionID},
|
||
|
{LangID: t.LangID, ScriptID: t.ScriptID},
|
||
|
} {
|
||
|
if x, err := addTags(id); err == nil && max.equalTags(x) {
|
||
|
t.setTagsFrom(id)
|
||
|
break
|
||
|
}
|
||
|
}
|
||
|
return t, nil
|
||
|
}
|