<?php

class EInvalidConfig extends Exception
{
}

class ConfigurationValidator
{
	public function validateConfig()
	{
		self::checkMode();
		self::checkDefaultLocale();
		self::checkCurrencyFormat();
		self::checkFirstDayOfWeek();
		self::checkEntryPage();
		self::checkMealplanFirstDayOfWeek();
		self::checkAutoNightModeRange();
	}


	private function checkMode()
	{
		$allowedModes = ["production", "dev", "demo", "prerelease"];
		if (!in_array(GROCY_MODE, $allowedModes))
		{
			throw new EInvalidConfig('Invalid mode "' . GROCY_MODE . '" set, only ' . implode(", ", $allowedModes) . " allowed");
		}
	}

	private function checkDefaultLocale()
	{
		if (!file_exists(__DIR__ . "/../localization/" . GROCY_DEFAULT_LOCALE))
		{
			throw new EInvalidConfig('Invalid locale "'. GROCY_DEFAULT_LOCALE . '" set, locale needs to exist in folder localization');
		}
	}

	private function checkFirstDayOfWeek()
	{
		if (!(GROCY_CALENDAR_FIRST_DAY_OF_WEEK == "" ||
			(is_numeric(GROCY_CALENDAR_FIRST_DAY_OF_WEEK) && GROCY_CALENDAR_FIRST_DAY_OF_WEEK >= 0 && GROCY_CALENDAR_FIRST_DAY_OF_WEEK <= 6)))
		{
			throw new EInvalidConfig('Invalid value for CALENDAR_FIRST_DAY_OF_WEEK');
		}
	}

	private function checkCurrencyFormat()
	{
		if (!(preg_match("/^([A-z]){3}$/", GROCY_CURRENCY)))
		{
			throw new EInvalidConfig('CURRENCY is not in ISO 4217 format (three letter code)');
		}
	}

	private function checkEntryPage()
	{
		$allowedPages = ["stock", "shoppinglist", "recipes", "chores", "tasks", "batteries", "equipment", "calendar", "mealplan"];
		if (!in_array(GROCY_ENTRY_PAGE, $allowedPages))
		{
			throw new EInvalidConfig('Invalid entry page "' . GROCY_ENTRY_PAGE . '" set, only ' . implode(", ", $allowedPages) . " allowed");
		}
	}

	private function checkMealplanFirstDayOfWeek()
	{
		if (!(GROCY_MEAL_PLAN_FIRST_DAY_OF_WEEK == "" ||
			(is_numeric(GROCY_MEAL_PLAN_FIRST_DAY_OF_WEEK) &&GROCY_MEAL_PLAN_FIRST_DAY_OF_WEEK >= 0 && GROCY_MEAL_PLAN_FIRST_DAY_OF_WEEK <= 6)))
		{
			throw new EInvalidConfig('Invalid value for MEAL_PLAN_FIRST_DAY_OF_WEEK');
		}
	}


	private function checkAutoNightModeRange()
	{
		global $GROCY_DEFAULT_USER_SETTINGS;
		if (!(preg_match("/^(?:2[0-3]|[01][0-9]):[0-5][0-9]$/", $GROCY_DEFAULT_USER_SETTINGS["auto_night_mode_time_range_from"])))
		{
			throw new EInvalidConfig('auto_night_mode_time_range_from is not in HH:mm format ('.$GROCY_DEFAULT_USER_SETTINGS["auto_night_mode_time_range_from"].')');
		}
		if (!(preg_match("/^(?:2[0-3]|[01][0-9]):[0-5][0-9]$/", $GROCY_DEFAULT_USER_SETTINGS["auto_night_mode_time_range_to"])))
		{
			throw new EInvalidConfig('auto_night_mode_time_range_to is not in HH:mm format ('.$GROCY_DEFAULT_USER_SETTINGS["auto_night_mode_time_range_to"].')');
		}
	}

}