const fs = require("fs");

// PART 1
{
	const result = fs.readFileSync("day_1.txt")
		.toString()
		.split("\n")
		.map(line => line.split("").find(isFinite) + line.split("").findLast(isFinite))
		.map(Number)
		.filter(isFinite)
		.reduce((acc, val) => acc + val, 0);

	console.log(result);
}

// PART 2
const digits = ["one", "two", "three", "four", "five", "six", "seven", "eight", "nine"];

function isNumber(char, i, arr) {
	return isFinite(char) || digits.some(digit => arr.slice(i).join("").startsWith(digit));
}

function getNumber(line, index) {
	if (isFinite(line.charAt(index)))
		return line.charAt(index);

	for (let i = 0; i < digits.length; i++)
		if (line.slice(index).startsWith(digits[i])) return (i + 1).toString();
}

{

	const result = fs.readFileSync("day_1.txt")
		.toString()
		.split("\n")
		.map(line => getNumber(line, line.split("").findIndex(isNumber)) + getNumber(line, line.split("").findLastIndex(isNumber)))
		.map(Number)
		.filter(isFinite)
		.reduce((acc, val) => acc + val, 0);

	console.log(result);
}