// Type definition
type GeneratorOptions = {
	charsQty?: number;
	isUppercase?: boolean;
	haveString?: boolean;
	haveNumbers?: boolean;
	haveSymbols?: boolean;
};

/**
 * Prepare an array or numbers based on ASCII table
 * @param low minimum value
 * @param high maximum value
 * @returns array of numbers
 */
const lowToHigh = (low: number, high: number): number[] => {
	const array: number[] = [];
	for (let i = low; i <= high; i++) {
		array.push(i);
	}

	return array;
};

const lowercaseCharactersCode = lowToHigh(97, 122);
const uppercaseCharactersCode = lowToHigh(65, 90);
const numberCharactersCode = lowToHigh(48, 57);
const symbolsCharactersCode = lowToHigh(33, 47)
	.concat(lowToHigh(58, 64))
	.concat(lowToHigh(123, 126))
	.concat(lowToHigh(91, 96));

/**
 * Get named params (object) and loop through it and apply conditionals
 * @param charsQty      string length
 * @param isUppercase   boolean param should include uppercase?
 * @param haveNumbers   boolean param should include numbers?
 * @param haveSymbols   boolean param should include special chars?
 * @returns string with password ready characteristics
 */
export const generator = (
	{
		charsQty = 10,
		isUppercase = false,
		haveString = true,
		haveNumbers = false,
		haveSymbols = false,
	}: GeneratorOptions = {
		charsQty: 10,
		isUppercase: false,
		haveString: true,
		haveNumbers: false,
		haveSymbols: false,
	}
): string => {
	let charactersCode: number[] = [];

	if (haveString)
		charactersCode = charactersCode.concat(lowercaseCharactersCode);
	if (isUppercase)
		charactersCode = charactersCode.concat(uppercaseCharactersCode);
	if (haveNumbers) charactersCode = charactersCode.concat(numberCharactersCode);
	if (haveSymbols)
		charactersCode = charactersCode.concat(symbolsCharactersCode);

	const password: string[] = [];
	if (charactersCode.length === 0) {
		return '';
	}
	for (let i = 0; i < charsQty; i++) {
		const char = Math.floor(Math.random() * charactersCode.length);
		password.push(String.fromCharCode(charactersCode[char]));
	}
	return password.join('');
};