Add to_search_normalized to search for characters with accents

library/MiscUtils.cpp

@@ -128,6 +128,45 @@ std::string toLower(const std::string &str)
     return rv;
 }
 
+static const char *normalized_table[256] = {
+        //.0  .1    .2    .3    .4    .5    .6    .7    .8    .9    .A    .B    .C    .D    .E    .F
+        NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, // 0.
+        NULL, NULL, NULL, NULL, NULL, "S", NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, // 1.
+        NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, // 2.
+        NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, // 3.
+        NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, // 4.
+        NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, // 5.
+        NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, // 6.
+        NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, // 7.
+        "C", "u", "e", "a", "a", "a", "a", "c", "e", "e", "e", "i", "i", "i", "A", "A", // 8.
+        "E", "ae", "Ae", "o", "o", "o", "u", "u", "y", "O", "U", "c", "L", "Y", NULL, "f", // 9.
+        "a", "i", "o", "u", "n", "N", "a", "o", NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, // A.
+        NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, // B.
+        NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, // C.
+        NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, // D.
+        NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, // E.
+        NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, // F.
+};
+
+std::string to_search_normalized(const std::string &str)
+{
+    std::stringbuf result;
+    for (char c : str)
+    {
+        const char *mapped = normalized_table[(uint8_t)c];
+        if (mapped == NULL)
+            result.sputc(tolower(c));
+        else
+            while (*mapped != '\0')
+            {
+                result.sputc(tolower(c));
+                ++mapped;
+            }
+    }
+
+    return result.str();
+}
+
 bool word_wrap(std::vector<std::string> *out, const std::string &str, size_t line_length)
 {
     out->clear();

library/include/MiscUtils.h

@@ -366,6 +366,7 @@ DFHACK_EXPORT std::string join_strings(const std::string &separator, const std::
 
 DFHACK_EXPORT std::string toUpper(const std::string &str);
 DFHACK_EXPORT std::string toLower(const std::string &str);
+DFHACK_EXPORT std::string to_search_normalized(const std::string &str);
 
 DFHACK_EXPORT bool word_wrap(std::vector<std::string> *out,
                              const std::string &str,

plugins/search.cpp

@@ -396,7 +396,7 @@ protected:
 
         clear_viewscreen_vectors();
 
-        string search_string_l = toLower(search_string);
+        string search_string_l = to_search_normalized(search_string);
         for (size_t i = 0; i < saved_list1.size(); i++ )
         {
             if (force_in_search(i))
@@ -409,7 +409,7 @@ protected:
                 continue;
 
             T element = saved_list1[i];
-            string desc = toLower(get_element_description(element));
+            string desc = to_search_normalized(get_element_description(element));
             if (desc.find(search_string_l) != string::npos)
             {
                 add_to_filtered_list(i);