Convert StringMatcher class to static and move code from FuzzySearch

Wox.Infrastructure/StringMatcher.cs

@@ -1,20 +1,21 @@
 using System;
-using System.Collections.Generic;
 using System.Linq;
-using Wox.Infrastructure;
+using System.Text;
 using Wox.Infrastructure.Logger;
+using Wox.Infrastructure.UserSettings;
 
 namespace Wox.Infrastructure
 {
     public static class StringMatcher
     {
+        public static string UserSettingSearchPrecision { get; set; }
+
+        [Obsolete("This method is obsolete and should not be used. Please use the static function StringMatcher.FuzzySearch")]
         public static int Score(string source, string target)
         {
             if (!string.IsNullOrEmpty(source) && !string.IsNullOrEmpty(target))
             {
-                FuzzyMatcher matcher = FuzzyMatcher.Create(target);
-                var score = matcher.Evaluate(source).Score;
-                return score;
+                return FuzzySearch(target, source, new MatchOption()).Score;               
             }
             else
             {
@@ -22,6 +23,97 @@ namespace Wox.Infrastructure
             }
         }
 
+        [Obsolete("This method is obsolete and should not be used. Please use the static function StringMatcher.FuzzySearch")]
+        public static bool IsMatch(string source, string target)
+        {
+            return FuzzySearch(target, source, new MatchOption()).Score > 0;
+        }
+
+        public enum SearchPrecisionScore
+        {
+            Regular = 50,
+            Low = 20,
+            None = 0
+        }
+
+        /// <summary>
+        /// refer to https://github.com/mattyork/fuzzy
+        /// </summary>
+        public static MatchResult FuzzySearch(string query, string stringToCompare, MatchOption opt)
+        {
+            if (string.IsNullOrEmpty(stringToCompare) || string.IsNullOrEmpty(query)) return new MatchResult { Success = false };
+
+            query.Trim();
+
+            var len = stringToCompare.Length;
+            var compareString = opt.IgnoreCase ? stringToCompare.ToLower() : stringToCompare;
+            var pattern = opt.IgnoreCase ? query.ToLower() : query;
+
+            var sb = new StringBuilder(stringToCompare.Length + (query.Length * (opt.Prefix.Length + opt.Suffix.Length)));
+            var patternIdx = 0;
+            var firstMatchIndex = -1;
+            var lastMatchIndex = 0;
+            char ch;
+            for (var idx = 0; idx < len; idx++)
+            {
+                ch = stringToCompare[idx];
+                if (compareString[idx] == pattern[patternIdx])
+                {
+                    if (firstMatchIndex < 0)
+                        firstMatchIndex = idx;
+                    lastMatchIndex = idx + 1;
+
+                    sb.Append(opt.Prefix + ch + opt.Suffix);
+                    patternIdx += 1;
+                }
+                else
+                {
+                    sb.Append(ch);
+                }
+
+                // match success, append remain char
+                if (patternIdx == pattern.Length && (idx + 1) != compareString.Length)
+                {
+                    sb.Append(stringToCompare.Substring(idx + 1));
+                    break;
+                }
+            }
+
+            // return rendered string if we have a match for every char
+            if (patternIdx == pattern.Length)
+            {
+                return new MatchResult
+                {
+                    Success = true,
+                    Value = sb.ToString(),
+                    Score = CalScore(query, stringToCompare, firstMatchIndex, lastMatchIndex - firstMatchIndex)
+                };
+            }
+
+            return new MatchResult { Success = false };
+        }
+
+        private static int CalScore(string query, string stringToCompare, int firstIndex, int matchLen)
+        {
+            //a match found near the beginning of a string is scored more than a match found near the end
+            //a match is scored more if the characters in the patterns are closer to each other, while the score is lower if they are more spread out
+            var score = 100 * (query.Length + 1) / ((1 + firstIndex) + (matchLen + 1));
+            //a match with less characters assigning more weights
+            if (stringToCompare.Length - query.Length < 5)
+                score = score + 20;
+            else if (stringToCompare.Length - query.Length < 10)
+                score = score + 10;
+
+            return score;
+        }
+
+        public static bool IsPreciciseMatch(this MatchResult matchResult)
+        {            
+            var precisionScore = (SearchPrecisionScore)Enum.Parse(typeof(SearchPrecisionScore), 
+                                                                            UserSettingSearchPrecision ?? SearchPrecisionScore.Regular.ToString());
+            return matchResult.Score >= (int)precisionScore;
+        }
+
         public static int ScoreForPinyin(string source, string target)
         {
             if (!string.IsNullOrEmpty(source) && !string.IsNullOrEmpty(target))
@@ -34,12 +126,12 @@ namespace Wox.Infrastructure
                 
                 if (Alphabet.ContainsChinese(source))
                 {
-                    FuzzyMatcher matcher = FuzzyMatcher.Create(target);
-                    var combination = Alphabet.PinyinComination(source);
-                    var pinyinScore = combination.Select(pinyin => matcher.Evaluate(string.Join("", pinyin)).Score)
+                    var combination = Alphabet.PinyinComination(source);                    
+                    var pinyinScore = combination
+                        .Select(pinyin => FuzzySearch(target, string.Join("", pinyin), new MatchOption()).Score)
                         .Max();
-                    var acronymScore = combination.Select(Alphabet.Acronym)
-                        .Select(pinyin => matcher.Evaluate(pinyin).Score)
+                    var acronymScore = combination.Select(Alphabet.Acronym)                        
+                        .Select(pinyin => FuzzySearch(target, pinyin, new MatchOption()).Score)
                         .Max();
                     var score = Math.Max(pinyinScore, acronymScore);
                     return score;
@@ -53,11 +145,37 @@ namespace Wox.Infrastructure
             {
                 return 0;
             }
+        }        
+    }
+
+    public class MatchResult
+    {
+        public bool Success { get; set; }
+        public int Score { get; set; }
+        /// <summary>
+        /// hightlight string
+        /// </summary>
+        public string Value { get; set; }
+    }
+
+    public class MatchOption
+    {
+        public MatchOption()
+        {
+            Prefix = "";
+            Suffix = "";
+            IgnoreCase = true;
         }
 
-        public static bool IsMatch(string source, string target)
-        {
-            return Score(source, target) > 0;
-        }
+        /// <summary>
+        /// prefix of match char, use for hightlight
+        /// </summary>
+        public string Prefix { get; set; }
+        /// <summary>
+        /// suffix of match char, use for hightlight
+        /// </summary>
+        public string Suffix { get; set; }
+
+        public bool IgnoreCase { get; set; }
     }
 }