Improve startup time

src/core/utils.cpp

@@ -5,12 +5,34 @@
  */
 
 #include "utils.h"
+#include <cctype>
 
 namespace mirai
 {
 bool isDate(const std::string &dateStr)
 {
-	std::regex regex("[0-9]{4}-[0-9]{2}-[0-9]{2}");
-	return std::regex_match(dateStr, regex);
+	// std regex are really slow
+	/*std::regex regex("[0-9]{4}-[0-9]{2}-[0-9]{2}");*/
+	/*return std::regex_match(dateStr, regex);*/
+
+	// Quick hand made check instead of regex until I rework date to use timestamp or std::chrono
+	if (dateStr.length() != 10) {
+		return false;
+	}
+
+	if (dateStr[4] != '-' || dateStr[7] != '-') {
+		return false;
+	}
+
+	for (int i = 0; i < dateStr.length(); ++i) {
+		if (i == 4 || i == 7) {
+			// These are the '-' characters
+			continue;
+		}
+		if (!isdigit(dateStr[i])) {
+			return false;
+		}
+	}
+	return true;
 }
 } // namespace mirai