From 39832a3e7198a99d27da392eb2f68045c09edb17 Mon Sep 17 00:00:00 2001
From: ddbb07 <31517774-ddbb07@users.noreply.gitlab.com>
Date: Sat, 15 Nov 2025 23:59:31 +0100
Subject: [PATCH] Reimplement weightedSearch

---
 apps/openmw/mwgui/settingswindow.cpp | 50 +++++++++++-----------------
 1 file changed, 19 insertions(+), 31 deletions(-)

diff --git a/apps/openmw/mwgui/settingswindow.cpp b/apps/openmw/mwgui/settingswindow.cpp
index 0e13e4df49..8b7a6385be 100644
--- a/apps/openmw/mwgui/settingswindow.cpp
+++ b/apps/openmw/mwgui/settingswindow.cpp
@@ -2,7 +2,6 @@
 
 #include <array>
 #include <iomanip>
-#include <regex>
 
 #include <unicode/locid.h>
 
@@ -944,37 +943,26 @@ namespace MWGui
 
     namespace
     {
-        std::string escapeRegex(const std::string& str)
+        std::vector<std::string> splitString(const std::string& inputString)
         {
-            static const std::regex specialChars(R"r([\^\.\[\$\(\)\|\*\+\?\{])r", std::regex_constants::extended);
-            return std::regex_replace(str, specialChars, R"(\$&)");
+            std::istringstream stringStream(inputString);
+            return { std::istream_iterator<std::string>(stringStream), std::istream_iterator<std::string>() };
         }
-
-        std::regex wordSearch(const std::string& query)
+        double weightedSearch(std::string corpus, std::string patternString)
         {
-            static const std::regex wordsRegex(R"([^[:space:]]+)", std::regex_constants::extended);
-            auto wordsBegin = std::sregex_iterator(query.begin(), query.end(), wordsRegex);
-            auto wordsEnd = std::sregex_iterator();
-            std::string searchRegex("(");
-            for (auto it = wordsBegin; it != wordsEnd; ++it)
-            {
-                if (it != wordsBegin)
-                    searchRegex += '|';
-                searchRegex += escapeRegex(query.substr(it->position(), it->length()));
-            }
-            searchRegex += ')';
-            // query had only whitespace characters
-            if (searchRegex == "()")
-                searchRegex = "^(.*)$";
-            return std::regex(searchRegex, std::regex_constants::extended | std::regex_constants::icase);
-        }
+            if (patternString.empty() || patternString.find_first_not_of(" ") == std::string::npos)
+                return 1.0;
 
-        double weightedSearch(const std::regex& regex, const std::string& text)
-        {
-            std::smatch matches;
-            std::regex_search(text, matches, regex);
-            // need a signed value, so cast to double (not an integer type to guarantee no overflow)
-            return static_cast<double>(matches.size());
+            Misc::StringUtils::lowerCaseInPlace(corpus);
+            Misc::StringUtils::lowerCaseInPlace(patternString);
+
+            const std::vector<std::string> patternArray = splitString(patternString);
+
+            double numberOfMatches = 0.0;
+            for (const std::string& word : patternArray)
+                numberOfMatches += corpus.find(word) != std::string::npos ? 1.0 : 0.0;
+
+            return numberOfMatches;
         }
     }
 
@@ -997,14 +985,14 @@ namespace MWGui
             constexpr bool operator<(const WeightedPage& rhs) const { return tie() < rhs.tie(); }
         };
 
-        std::regex searchRegex = wordSearch(mScriptFilter->getCaption());
+        std::string searchPattern = mScriptFilter->getCaption();
         std::vector<WeightedPage> weightedPages;
         weightedPages.reserve(LuaUi::scriptSettingsPageCount());
         for (size_t i = 0; i < LuaUi::scriptSettingsPageCount(); ++i)
         {
             LuaUi::ScriptSettingsPage page = LuaUi::scriptSettingsPageAt(i);
-            double nameWeight = weightedSearch(searchRegex, page.mName);
-            double hintWeight = weightedSearch(searchRegex, page.mSearchHints);
+            double nameWeight = weightedSearch(page.mName, searchPattern);
+            double hintWeight = weightedSearch(page.mSearchHints, searchPattern);
             if ((nameWeight + hintWeight) > 0)
                 weightedPages.push_back({ i, page.mName, -nameWeight, -hintWeight });
         }