More string comparisons

src/Engine/Unicode.cpp

@@ -27,6 +27,7 @@
 #endif
 #define WIN32_LEAN_AND_MEAN
 #include <windows.h>
+#include <shlwapi.h>
 #else
 #include <cassert>
 #endif
@@ -249,13 +250,49 @@ bool naturalCompare(const std::string &a, const std::string &b)
 	else
 #endif
 	{
-		// sorry unix users you get ASCII sort
-		std::string::const_iterator i, j;
-		for (i = a.begin(), j = b.begin(); i != a.end() && j != b.end() && std::tolower(*i, utf8) == std::tolower(*j, utf8); ++i, ++j);
-		return (i != a.end() && j != b.end() && std::tolower(*i, utf8) < tolower(*j, utf8));
+		// fallback to lexographical sort
+		return caseCompare(a, b);
 	}
 }
 
+/**
+ * Compares two UTF-8 strings ignoring case.
+ * @param a String A.
+ * @param b String B.
+ * @return String A comes before String B.
+ */
+bool caseCompare(const std::string &a, const std::string &b)
+{
+#ifdef _WIN32
+	std::wstring wa = convMbToWc(a, CP_UTF8);
+	std::wstring wb = convMbToWc(b, CP_UTF8);
+	return (StrCmpIW(wa.c_str(), wb.c_str()) < 0);
+#else
+	return (std::use_facet< std::collate<char> >(utf8).compare(&a[0], &a[a.size()], &b[0], &b[b.size()]) < 0);
+#endif
+}
+
+/**
+ * Searches for a substring in another string ignoring case.
+ * @param haystack String to search.
+ * @param needle String to find.
+ * @return True if the needle is in the haystack.
+ */
+bool caseFind(const std::string &haystack, const std::string &needle)
+{
+#ifdef _WIN32
+	std::wstring wa = convMbToWc(haystack, CP_UTF8);
+	std::wstring wb = convMbToWc(needle, CP_UTF8);
+	return (StrStrIW(wa.c_str(), wb.c_str()) != NULL);
+#else
+	std::wstring wa = convMbToWc(haystack, 0);
+	std::wstring wb = convMbToWc(needle, 0);
+	std::use_facet< std::ctype<wchar_t> >(utf8).toupper(&wa[0], &wb[wb.size()]);
+	std::use_facet< std::ctype<wchar_t> >(utf8).toupper(&wb[0], &wb[wb.size()]);
+	return (wa.find(wb) != std::wstring::npos);
+#endif
+}
+
 /**
  * Uppercases a UTF-8 string, modified in place.
  * Used for case-insensitive comparisons.
@@ -276,6 +313,26 @@ void upperCase(std::string &s)
 #endif
 }
 
+/**
+ * Lowercases a UTF-8 string, modified in place.
+ * Used for case-insensitive comparisons.
+ * @param s Source string.
+ */
+void lowerCase(std::string &s)
+{
+	if (s.empty())
+		return;
+#ifdef _WIN32
+	std::wstring ws = convMbToWc(s, CP_UTF8);
+	CharLowerW(&ws[0]);
+	s = convWcToMb(ws, CP_UTF8);
+#else
+	std::wstring ws = convMbToWc(s, 0);
+	std::use_facet< std::ctype<wchar_t> >(utf8).tolower(&ws[0], &ws[ws.size()]);
+	s = convWcToMb(ws, 0);
+#endif
+}
+
 /**
  * Replaces every instance of a substring.
  * @param str The string to modify.

src/Engine/Unicode.h

@@ -68,8 +68,14 @@ namespace Unicode
 
 	/// Compares two strings by natural order.
 	bool naturalCompare(const std::string &a, const std::string &b);
+	/// Compares two strings case-insensitive.
+	bool caseCompare(const std::string &a, const std::string &b);
+	/// Find a string in another case-insensitive.
+	bool caseFind(const std::string &haystack, const std::string &needle);
 	/// Uppercases a string in place.
 	void upperCase(std::string &s);
+	/// Lowercases a string in place.
+	void upperCase(std::string &s);
 	/// Replaces a substring.
 	void replace(std::string &str, const std::string &find, const std::string &replace);
 	/// Formats an integer value as number with separators.