Add Acronym Support for Fuzzy Search

Flow.Launcher.Infrastructure/PinyinAlphabet.cs

@@ -1,5 +1,6 @@
 using System;
 using System.Collections.Concurrent;
+using System.Collections.Generic;
 using System.Linq;
 using System.Text;
 using JetBrains.Annotations;
@@ -8,22 +9,117 @@
 
 namespace Flow.Launcher.Infrastructure
 {
+    public class TranslationMapping
+    {
+        private bool constructed;
+
+        private List<int> originalIndexs = new List<int>();
+        private List<int> translatedIndexs = new List<int>();
+        private int translaedLength = 0;
+
+        public string key { get; private set; }
+
+        public void setKey(string key)
+        {
+            this.key = key;
+        }
+
+        public void AddNewIndex(int originalIndex, int translatedIndex, int length)
+        {
+            if (constructed)
+                throw new InvalidOperationException("Mapping shouldn't be changed after constructed");
+
+            originalIndexs.Add(originalIndex);
+            translatedIndexs.Add(translatedIndex);
+            translatedIndexs.Add(translatedIndex + length);
+            translaedLength += length - 1;
+        }
+
+        public int MapToOriginalIndex(int translatedIndex)
+        {
+            if (translatedIndex > translatedIndexs.Last())
+                return translatedIndex - translaedLength - 1;
+
+            int lowerBound = 0;
+            int upperBound = originalIndexs.Count - 1;
+
+            int count = 0;
+
+            // Corner case handle
+            if (translatedIndex < translatedIndexs[0])
+                return translatedIndex;
+            if (translatedIndex > translatedIndexs.Last())
+            {
+                int indexDef = 0;
+                for (int k = 0; k < originalIndexs.Count; k++)
+                {
+                    indexDef += translatedIndexs[k * 2 + 1] - translatedIndexs[k * 2];
+                }
+
+                return translatedIndex - indexDef - 1;
+            }
+
+            // Binary Search with Range
+            for (int i = originalIndexs.Count / 2;; count++)
+            {
+                if (translatedIndex < translatedIndexs[i * 2])
+                {
+                    // move to lower middle
+                    upperBound = i;
+                    i = (i + lowerBound) / 2;
+                }
+                else if (translatedIndex > translatedIndexs[i * 2 + 1] - 1)
+                {
+                    lowerBound = i;
+                    // move to upper middle
+                    // due to floor of integer division, move one up on corner case
+                    i = (i + upperBound + 1) / 2;
+                }
+                else
+                    return originalIndexs[i];
+
+                if (upperBound - lowerBound <= 1 &&
+                    translatedIndex > translatedIndexs[lowerBound * 2 + 1] &&
+                    translatedIndex < translatedIndexs[upperBound * 2])
+                {
+                    int indexDef = 0;
+
+                    for (int j = 0; j < upperBound; j++)
+                    {
+                        indexDef += translatedIndexs[j * 2 + 1] - translatedIndexs[j * 2];
+                    }
+
+                    return translatedIndex - indexDef - 1;
+                }
+            }
+        }
+
+        public void endConstruct()
+        {
+            if (constructed)
+                throw new InvalidOperationException("Mapping has already been constructed");
+            constructed = true;
+        }
+    }
+
     public interface IAlphabet
     {
-        string Translate(string stringToTranslate);
+        public (string translation, TranslationMapping map) Translate(string stringToTranslate);
     }
 
     public class PinyinAlphabet : IAlphabet
     {
-        private ConcurrentDictionary<string, string> _pinyinCache = new ConcurrentDictionary<string, string>();
+        private ConcurrentDictionary<string, (string translation, TranslationMapping map)> _pinyinCache =
+            new ConcurrentDictionary<string, (string translation, TranslationMapping map)>();
+
         private Settings _settings;
 
         public void Initialize([NotNull] Settings settings)
         {
             _settings = settings ?? throw new ArgumentNullException(nameof(settings));
         }
 
-        public string Translate(string content)
+        public (string translation, TranslationMapping map) Translate(string content)
         {
             if (_settings.ShouldUsePinyin)
             {
@@ -34,21 +130,15 @@ public string Translate(string content)
                         var resultList = WordsHelper.GetPinyinList(content);
 
                         StringBuilder resultBuilder = new StringBuilder();
-
-                        for (int i = 0; i < resultList.Length; i++)
-                        {
-                            if (content[i] >= 0x3400 && content[i] <= 0x9FD5)
-                                resultBuilder.Append(resultList[i].First());
-                        }
-
-                        resultBuilder.Append(' ');
+                        TranslationMapping map = new TranslationMapping();
 
                         bool pre = false;
 
                         for (int i = 0; i < resultList.Length; i++)
                         {
                             if (content[i] >= 0x3400 && content[i] <= 0x9FD5)
                             {
+                                map.AddNewIndex(i, resultBuilder.Length, resultList[i].Length + 1);
                                 resultBuilder.Append(' ');
                                 resultBuilder.Append(resultList[i]);
                                 pre = true;
@@ -60,15 +150,21 @@ public string Translate(string content)
                                     pre = false;
                                     resultBuilder.Append(' ');
                                 }
+
                                 resultBuilder.Append(resultList[i]);
                             }
                         }
 
-                        return _pinyinCache[content] = resultBuilder.ToString();
+                        map.endConstruct();
+
+                        var key = resultBuilder.ToString();
+                        map.setKey(key);
+
+                        return _pinyinCache[content] = (key, map);
                     }
                     else
                     {
-                        return content;
+                        return (content, null);
                     }
                 }
                 else
@@ -78,7 +174,7 @@ public string Translate(string content)
             }
             else
             {
-                return content;
+                return (content, null);
             }
         }
     }