/// <summary>
/// Register language tag
/// </summary>
/// <param name="languageTag"></param>
/// <exception cref="ArgumentNullException"></exception>
public void RegisterTag(LanguageTag languageTag)
{
if (languageTag == null)
{
throw new ArgumentNullException(nameof(languageTag));
}
var hashcode = languageTag.GetHashCode();
// ReSharper disable once InconsistentlySynchronizedField
if (_items.Any(x => x.HashCodeCached == hashcode))
{
return;
}
lock (_cacheLockObj) {
if (_items.Any(x => x.HashCodeCached == hashcode))
{
return;
}
//this will update all item's priority
_items.Add(new FallbackItem(languageTag));
}
}
/// <summary>
/// 获得 LanguageTag 的完整度级别，该级别用于 Add 方法对同语言标记做优先级自动优化排列时的参考
/// 级别从 0 到 4，数字越小，优先级越高
/// LanguageTag 完整性越高，优先级越高——优先命中高优先级的，最低的 Language only 作为兜底候选项
/// l 0
/// l-r 1
/// l-s 2
/// l-s-r 3
/// l-s-r-p 4
/// </summary>
/// <param name="languageTag"></param>
/// <returns></returns>
private static int GetFullLevel(LanguageTag languageTag)
{
if (languageTag == null)
{
return(-1);
}
if (!languageTag.Language.IsSet())
{
return(-1);
}
if (languageTag.Language.IsSet() && languageTag.Script.IsSet() && languageTag.Region.IsSet() && languageTag.PrivateUse.IsSet())
{
return(4);
}
if (languageTag.Language.IsSet() && languageTag.Script.IsSet() && languageTag.Region.IsSet())
{
return(3);
}
if (languageTag.Language.IsSet() && languageTag.Script.IsSet())
{
return(2);
}
if (languageTag.Language.IsSet() && languageTag.Region.IsSet())
{
return(1);
}
return(0);
}
/// <summary>
/// Get suitable tags
/// </summary>
/// <param name="languageTag"></param>
/// <returns></returns>
public IEnumerable <LanguageTag> GetSuitableTags(LanguageTag languageTag)
{
if (_cachedResults.TryGetValue(languageTag.GetHashCode(), out var results))
{
return(results.Select(s => s.Value));
}
if (!_items.Any())
{
return(Enumerable.Empty <LanguageTag>());
}
results = new List <FallbackItem>();
var orderedItems = _items.OrderByDescending(o => o.Priority).ToList();
var skipHashCodes = new List <int>();
//step.1 filter all results by this order: ExactMatch, DefaultRegion, ScriptMatch and LanguageMatch
foreach (var level in _matchLevels)
{
results.AddRange(Filter(orderedItems, languageTag, level, skipHashCodes));
}
//step.2 add all results which priority less than the min of the result that got from step.1
results.AddRange(Filter(orderedItems, results.Min(m => m.Priority), skipHashCodes));
//step.3 add default language tag (in this case, the most less priority) if need.
AddMostLessPriorityIfNeed(results, skipHashCodes);
//step.4 clear skipped hashcode cache
skipHashCodes.Clear();
return(Remember(languageTag, results));
}
/// <summary>
/// Has cached result
/// </summary>
/// <param name="languageTag"></param>
/// <returns></returns>
public bool HashCachedResult(LanguageTag languageTag)
{
if (languageTag == null)
{
return(false);
}
return(_cachedResults.ContainsKey(languageTag.GetHashCode()));
}
/// <summary>
/// Contains
/// </summary>
/// <param name="languageTag"></param>
/// <returns></returns>
public bool Contains(LanguageTag languageTag)
{
if (languageTag == null)
{
return(false);
}
return(_items.ContainsGlobalKey(languageTag.GlobalKey));
}
internal LanguageTag(string originalLanguageTag, string language, string script, string region, string privateUse, LanguageTag parent, CultureInfo cultureInfo)
{
OriginalLanguageTag = originalLanguageTag;
LowerCaseLanguageTag = originalLanguageTag.ToLowerInvariant();
Language = language;
Script = script;
Region = region;
PrivateUse = privateUse;
Parent = parent;
CultureInfo = cultureInfo;
NativeNameTitleCase = CultureInfo != null?CultureInfo.TextInfo.ToTitleCase(CultureInfo.NativeName) : "OriginalLangTag";
GlobalKey = $"po:{OriginalLanguageTag}".ToLowerInvariant();
Alias = OriginalLanguageTag;
}
private IEnumerable <LanguageTag> Remember(LanguageTag left, List <FallbackItem> filteredItems)
{
lock (_cacheLockObj) {
var hashcode = left.GetHashCode();
if (_cachedResults.ContainsKey(hashcode))
{
_cachedResults[hashcode] = filteredItems;
}
else
{
_cachedResults.Add(hashcode, filteredItems);
}
}
return(filteredItems.Select(s => s.Value));
}
private IEnumerable <FallbackItem> Filter(List <FallbackItem> orderedItems, LanguageTag languageTag, MatchLevel matchLevel, List <int> skipHashCodes)
{
foreach (var item in orderedItems)
{
if (skipHashCodes.Contains(item.HashCodeCached))
{
continue;
}
var score = LanguageTagMatcher.Match(languageTag, item.Value, matchLevel);
if (score > 0)
{
skipHashCodes.Add(item.HashCodeCached);
yield return(item);
}
}
}
public LanguageTag Build()
{
//Load any parent
UpdateParent();
//Update culture info
UpdateCultureInfo();
var tag = new LanguageTag(OriginalLanguageTag, Language, Script, Region, PrivateUse, Parent, CultureInfo);
//Update alias
if (!string.IsNullOrWhiteSpace(Alias))
{
tag.UpdateAlias(Alias);
}
return(tag);
}
/// <summary>
/// Convert <see cref="LanguageTag"/> to <see cref="Locale"/>.
/// </summary>
/// <param name="languageTag"></param>
/// <returns></returns>
public static Locale AsLocale(this LanguageTag languageTag)
{
if (languageTag == null)
{
languageTag = LanguageTag.Current;
}
if (languageTag.Region.IsSet())
{
if (EnumsNET.Enums.TryParse(
$"{languageTag.Language}_{languageTag.Region.ToUpperInvariant()}",
true,
out Locale locale1))
{
return(locale1);
}
}
return(EnumsNET.Enums.TryParse(languageTag.Language, true, out Locale locale2)
? locale2
: LanguageTag.DefaultLocale);
}
/// <summary>
/// Looks up in the passed collection of supported AppLanguages the language that is best matched
/// to this langtag. I.e. the written AppLanguage that a user understanding this langtag
/// will most-likely understand.
/// </summary>
/// <param name="leftLanguageTag"></param>
/// <param name="rightLanguageTags"></param>
/// <param name="matchedTag"></param>
/// <param name="matchLevel"></param>
/// <returns>Selected CultureInfoEx instance from the AppLanguages collection or null if there was no match.</returns>
public static int Match(LanguageTag leftLanguageTag, LanguageTag[] rightLanguageTags, out LanguageTag matchedTag, MatchLevel matchLevel = MatchLevel.LanguageMatch)
{
int matchedScore = 0;
matchedTag = null;
foreach (LanguageTag rightLanguageTag in rightLanguageTags)
{
int score = Match(leftLanguageTag, rightLanguageTag, matchLevel);
if (score > matchedScore)
{
matchedScore = score;
matchedTag = rightLanguageTag;
if (matchedScore == 100)
{
// Can't beat an exact match.
break;
}
}
}
return(matchedScore);
}
/// <summary>
/// Performs 'language matching' between lang described by this (A)
/// and language decibed by i_rhs (B). Essentially, returns an assessment of
/// how well a speaker of A will understand B.
/// The key points are as follows:
/// · The Script is almost as relevant as the language itself; that is, if
/// you speak a language but do not understand the script, you cannot
/// read that language. Thus a mismatch in Script should score low.
/// · The Region is less relevant than Script to understanding of language.
/// The one exception to this is where the Region has traditionally been
/// used to also indicate the Script. E.g.
/// zh-CH -> Chinese (Simplified) i.e. zh-Hans
/// zh-TW -> Chinese (Traditional) i.e. zh-Hant
/// In these cases we normalize all legacy langtags to their new values
/// before matching. E.g. zh-CH is normalized to zh-Hans.
/// «LX113»
/// </summary>
/// <param name="leftLanguageTag"></param>
/// <param name="rightLanguageTag"></param>
/// <param name="matchLevel"></param>
/// <returns>
/// Returns a score on to what extent the two languages match. The value ranges from
/// 100 (exact match) down to 0 (fundamental language tag mismatch), with values
/// in between which may be used to compare quality of a match, larger the value
/// meaning better quality.
/// </returns>
/// <remarks>
/// Matching values:
/// RHS
/// this lang lang+script lang+region lang+script+region
/// ----------------------------------------------------------------------------------
/// lang | A D C D
/// lang+script | D A D B
/// lang+region | C D A D
/// lang+script+region | D B D A
///
/// NB: For the purposes of the logic above, lang incorporates Language + PrivateUse subtags.
///
/// A. Exact match (100)
/// All three subtags match.
/// B. Unbalanced Region Mismatch (99) [zh, zh-HK] [zh-Hans, zh-Hans-HK]
/// Language and Script match;
/// one side has Region set while the other doesn't.
/// Here there is the possibility that due to defaults Region matches.
/// C. Balanced Region Mismatch (98) [zh-IK, zh-HK] [zh-Hans-IK, zh-Hans-HK]
/// Language and Script match;
/// both sides have Region set but to different values.
/// Here there is NO possibility that Region matches.
/// D. Unbalanced Script Mismatch (97) [zh-HK, zh-Hant-HK]
/// Language matches, Region may match;
/// one side has Script set while the other doesn't.
/// Here there is the possibility that due to defaults Script matches.
/// E. Balanced Script Mismatch (96)
/// Language matches, Region may match;
/// both sides have Script set but to different values.
/// Here there is NO possibility that Script matches.
/// F. Language Mismatch (0)
/// Language doesn't match.
/// </remarks>
/// <seealso href="http://msdn.microsoft.com/en-us/library/windows/apps/jj673578.aspx"/>
public static int Match(LanguageTag leftLanguageTag, LanguageTag rightLanguageTag, MatchLevel matchLevel = MatchLevel.LanguageMatch)
{
if (leftLanguageTag == null)
{
throw new ArgumentNullException(nameof(leftLanguageTag));
}
if (rightLanguageTag == null)
{
throw new ArgumentNullException(nameof(rightLanguageTag));
}
if (leftLanguageTag.Language.IsNullOrEmpty() || rightLanguageTag.Language.IsNullOrEmpty())
{
return(0);
}
//Init
bool[] init(string l, string r) => new[] { 0 == string.Compare(l, r, StringComparison.OrdinalIgnoreCase), l.IsNotNullNorEmpty(), r.IsNotNullNorEmpty() };
var L = init(leftLanguageTag.Language, rightLanguageTag.Language);
var S = init(leftLanguageTag.Script, rightLanguageTag.Script);
var R = init(leftLanguageTag.Region, rightLanguageTag.Region);
var P = init(leftLanguageTag.PrivateUse, rightLanguageTag.PrivateUse);
// Language incorporates Language + PrivateUse subtags for our logic here.
L[0] = L[0] && P[0];
L[1] = L[1] || P[1];
L[2] = L[2] || P[2];
// Logic.
int score = 100;
// F.
if (!L[0])
{
return(0);
}
// A.
if (S[0] && R[0] && P[0])
{
return(score);
}
--score;
if (matchLevel != MatchLevel.ExactMatch)
{
// B.
if (S[0] && !R[0] && R[1] != R[2])
{
return(score);
}
--score;
if (matchLevel != MatchLevel.DefaultRegion)
{
// C.
if (S[0] && !R[0] && R[1] == R[2])
{
return(score);
}
--score;
if (matchLevel != MatchLevel.ScriptMatch)
{
// D.
if (!S[0] && S[1] != S[2])
{
return(score);
}
--score;
// E.
if (!S[0] && S[1] == S[2])
{
return(score);
}
}
//--score;
}
}
// F.
return(0);
}
/// <summary>
/// Match
/// </summary>
/// <param name="appLanguages"></param>
/// <param name="matchedTag"></param>
/// <param name="matchLevel"></param>
/// <returns></returns>
public int Match(LanguageTag[] appLanguages, out LanguageTag matchedTag, MatchLevel matchLevel = MatchLevel.LanguageMatch)
{
return(LanguageTagMatcher.Match(this, appLanguages, out matchedTag, matchLevel));
}
// [IEquatable<LanguageTag>]
/// <summary>
/// Equals
/// </summary>
/// <param name="other"></param>
/// <returns></returns>
public bool Equals(LanguageTag other)
{
return(0 == string.CompareOrdinal(LowerCaseLanguageTag, other.LowerCaseLanguageTag));
}
// [IComparable<LanguageTag>]
/// <summary>
/// CompareTo
/// </summary>
/// <param name="other"></param>
/// <returns></returns>
public int CompareTo(LanguageTag other)
{
return(string.CompareOrdinal(LowerCaseLanguageTag, other.LowerCaseLanguageTag));
}
/// <summary>
/// Match
/// </summary>
/// <param name="appLanguage"></param>
/// <param name="matchLevel"></param>
/// <returns></returns>
public int Match(LanguageTag appLanguage, MatchLevel matchLevel = MatchLevel.LanguageMatch)
{
return(LanguageTagMatcher.Match(this, appLanguage, matchLevel));
}
/// <summary>
/// Create a new instance for <see cref="FallbackItem"/>
/// </summary>
/// <param name="languageTag"></param>
public FallbackItem(LanguageTag languageTag)
{
Value = languageTag ?? throw new ArgumentNullException(nameof(languageTag));
HashCodeCached = Value.GetHashCode();
FullLevel = GetFullLevel(Value);
}
