#include "stdafx.h"
#include "Configuration.h"

#include <mutex>
#include <string>
#include <unordered_map>

static bool TryParseHHMM(const std::string& text, int& outMinutes)
{
	int hour = 0;
	int minute = 0;
	if (sscanf_s(text.c_str(), "%d:%d", &hour, &minute) != 2) return false;
	if (hour < 0 || hour >= 24) return false;
	if (minute < 0 || minute >= 60) return false;
	outMinutes = hour * 60 + minute;
	return true;
}

BOOL CConfiguration::getProductionShiftStartMinutes(int& dayStartMinutes, int& nightStartMinutes)
{
	struct CachedShift {
		BOOL ok = FALSE;
		int day = 0;
		int night = 0;
		bool inited = false;
	};

	static std::mutex s_mtx;
	static std::unordered_map<std::string, CachedShift> s_cache;

	const std::string filePath((LPCSTR)(LPCTSTR)m_strFilepath);
	{
		std::lock_guard<std::mutex> g(s_mtx);
		auto it = s_cache.find(filePath);
		if (it != s_cache.end() && it->second.inited) {
			dayStartMinutes = it->second.day;
			nightStartMinutes = it->second.night;
			return it->second.ok;
		}
	}

	char buf[64] = {};
	GetPrivateProfileStringA("Production", "DayShiftStart", "08:00", buf, (DWORD)sizeof(buf), m_strFilepath);
	std::string dayStr(buf);

	GetPrivateProfileStringA("Production", "NightShiftStart", "", buf, (DWORD)sizeof(buf), m_strFilepath);
	std::string nightStr(buf);

	const int kDefaultDay = 8 * 60;
	const int kDefaultNight = 20 * 60;

	bool okDay = TryParseHHMM(dayStr, dayStartMinutes);
	bool okNight = false;
	if (!nightStr.empty()) okNight = TryParseHHMM(nightStr, nightStartMinutes);

	if (!okDay) dayStartMinutes = kDefaultDay;
	if (!okNight) nightStartMinutes = (dayStartMinutes + 12 * 60) % (24 * 60);

	if (dayStartMinutes == nightStartMinutes) {
		dayStartMinutes = kDefaultDay;
		nightStartMinutes = kDefaultNight;
		{
			std::lock_guard<std::mutex> g(s_mtx);
			s_cache[filePath] = CachedShift{ FALSE, dayStartMinutes, nightStartMinutes, true };
		}
		return FALSE;
	}

	const BOOL ok = (okDay && (nightStr.empty() ? TRUE : okNight)) ? TRUE : FALSE;
	{
		std::lock_guard<std::mutex> g(s_mtx);
		s_cache[filePath] = CachedShift{ ok, dayStartMinutes, nightStartMinutes, true };
	}
	return ok;
}