Replace ilexicographical_compare, iequals usage with locale::to_lower

Using boost::locale::to_lower is less wrong than using the
boost::ilexicographical_compare and boost::iequals functions, as the
latter don't case fold non-ASCII UTF-8 characters.

src/api/game/game.cpp

@@ -29,6 +29,7 @@
 #include <thread>
 
 #include <boost/algorithm/string.hpp>
+#include <boost/locale.hpp>
 
 #include "api/api_database.h"
 #include "api/helpers/logging.h"
@@ -169,7 +170,8 @@ void Game::LoadPlugins(const std::vector<std::string>& plugins,
           logger->trace("Loading {}", pluginName);
         }
         const bool loadHeader =
-            boost::iequals(pluginName, masterFile_) || loadHeadersOnly;
+            loadHeadersOnly ||
+            boost::locale::to_lower(pluginName) == lowercasedMasterFilename_;
         try {
           cache_->AddPlugin(Plugin(
               Type(),  cache_, loadOrderHandler_, DataPath() / u8path(pluginName), loadHeader));
@@ -209,7 +211,7 @@ std::set<std::shared_ptr<const PluginInterface>> Game::GetLoadedPlugins()
 }
 
 void Game::IdentifyMainMasterFile(const std::string& masterFile) {
-  masterFile_ = masterFile;
+  lowercasedMasterFilename_ = boost::locale::to_lower(masterFile);
 }
 
 std::vector<std::string> Game::SortPlugins(

src/api/game/game.h

@@ -86,7 +86,7 @@ private:
   const GameType type_;
   const std::filesystem::path gamePath_;
 
-  std::string masterFile_;
+  std::string lowercasedMasterFilename_;
 };
 }
 #endif

src/api/metadata/file.cpp

@@ -24,7 +24,7 @@
 
 #include "loot/metadata/file.h"
 
-#include <boost/algorithm/string.hpp>
+#include <boost/locale.hpp>
 
 #include "api/metadata/yaml/file.h"
 
@@ -39,11 +39,11 @@ File::File(const std::string& name,
     ConditionalMetadata(condition) {}
 
 bool File::operator<(const File& rhs) const {
-  return boost::ilexicographical_compare(GetName(), rhs.GetName());
+  return boost::locale::to_lower(name_) < boost::locale::to_lower(rhs.name_);
 }
 
 bool File::operator==(const File& rhs) const {
-  return boost::iequals(GetName(), rhs.GetName());
+  return boost::locale::to_lower(name_) == boost::locale::to_lower(rhs.name_);
 }
 
 std::string File::GetName() const { return name_; }

src/api/metadata/plugin_metadata.cpp

@@ -276,8 +276,9 @@ bool PluginMetadata::IsRegexPlugin() const {
 }
 
 bool PluginMetadata::operator==(const PluginMetadata& rhs) const {
-  if (IsRegexPlugin() == rhs.IsRegexPlugin())
-    return boost::iequals(name_, rhs.GetName());
+  if (IsRegexPlugin() == rhs.IsRegexPlugin()) {
+    return GetLowercasedName() == rhs.GetLowercasedName();
+  }
 
   if (IsRegexPlugin())
     return regex_match(rhs.GetName(),
@@ -292,11 +293,7 @@ bool PluginMetadata::operator!=(const PluginMetadata& rhs) const {
 }
 
 bool PluginMetadata::operator==(const std::string& rhs) const {
-  if (IsRegexPlugin())
-    return regex_match(PluginMetadata(rhs).GetName(),
-                       regex(name_, regex::ECMAScript | regex::icase));
-  else
-    return boost::iequals(name_, PluginMetadata(rhs).GetName());
+  return *this == PluginMetadata(rhs);
 }
 
 bool PluginMetadata::operator!=(const std::string& rhs) const {

src/api/plugin.cpp

@@ -263,7 +263,7 @@ uintmax_t Plugin::GetFileSize(std::filesystem::path pluginPath) {
 }
 
 bool Plugin::operator<(const Plugin& rhs) const {
-  return boost::ilexicographical_compare(name_, rhs.name_);
+  return GetLowercasedName() < rhs.GetLowercasedName();
 }
 
 bool Plugin::IsActive() const { return isActive_; }

src/api/sorting/plugin_sorter.cpp

@@ -275,9 +275,10 @@ void PluginSorter::AddPluginVertices(Game& game) {
 
 bool PluginSorter::GetVertexByName(const std::string& name,
                                    vertex_t& vertexOut) const {
+  auto lowercasedName = boost::locale::to_lower(name);
   for (const auto& vertex :
        boost::make_iterator_range(boost::vertices(graph_))) {
-    if (boost::iequals(graph_[vertex].GetName(), name)) {
+    if (graph_[vertex].GetLowercasedName() == lowercasedName) {
       vertexOut = vertex;
       return true;
     }