public static (string sentence, string?highlighter) Highlight(this IMorphologicalAnalyzer <IpadicEntry> analyzer, string haystack, string needle)
{
var needleMorphemes = analyzer
.ParseToEntries(needle)
.Where(e => e.IsRegular)
.ToList();
var haystackMorphemes = analyzer
.ParseToEntries(haystack)
.Where(e => e.IsRegular)
.ToList();
if (haystackMorphemes.Count == 0 || needleMorphemes.Count == 0)
{
return(haystack, null);
}
var values = new List <int>(haystackMorphemes.Count);
for (int i = 0; i < haystackMorphemes.Count; ++i)
{
var count = Enumerable
.Zip(haystackMorphemes.Skip(i), needleMorphemes)
.Count(pair => pair.First.DictionaryForm == pair.Second.DictionaryForm);
values.Add(count);
}
var start = EnumerableExt.MaxBy(values.Indexed(), p => p.element).index;
var highlighter = GetHighlighterFor(haystack);
var haystackStrings = haystackMorphemes.Select(m => m.SurfaceForm).Materialize();
var strings = haystackStrings
.Take(start)
.Append(highlighter)
.Concat(haystackStrings.Skip(start).Take(values[start]))
.Append(highlighter)
.Concat(haystackStrings.Skip(start + values[start]));
return(string.Concat(strings), highlighter);
}
