aoc-2020-day4

p1.hs

{-# LANGUAGE OverloadedStrings #-}

module Main where

import qualified Data.Text.IO as TIO
import qualified Data.Text as T

passportTexts = T.splitOn "\n\n"

required =
  [ "byr:",
    "iyr:",
    "eyr:",
    "hgt:",
    "hcl:",
    "ecl:",
    "pid:"
  ]

isValid p = all (`T.isInfixOf` p) required

main = do
  text <- TIO.readFile "./d4.txt"
  print $ length $ filter isValid $ passportTexts text

p2.hs

{-# LANGUAGE OverloadedStrings #-}

module Main where

import qualified Data.Text.IO as TIO
import qualified Data.Text as T
import qualified Text.Read as TR
import qualified Data.Char as C

required =
  [
    "byr:",
    "iyr:",
    "eyr:",
    "hgt:",
    "hcl:",
    "ecl:",
    "pid:"
  ]

isValid p = all (`T.isInfixOf` p) required

passportTexts =
  map (T.split (`elem` ['\n', ' '])) .
  filter isValid .
  T.splitOn "\n\n"

validateIntBetween s e = (== (Just True)) . fmap (\v -> s <= v && v <= e) . TR.readMaybe . T.unpack

isValidField fld =
  case T.splitAt 4 $ T.strip fld of
    ("byr:", v) -> validateIntBetween 1920 2002 v
    ("iyr:", v) -> validateIntBetween 2010 2020 v
    ("eyr:", v) -> validateIntBetween 2020 2030 v
    ("hgt:", v) ->
      case (T.dropEnd 2 v, T.takeEnd 2 v) of
        (n, "cm") -> validateIntBetween 150 193 n
        (n, "in") -> validateIntBetween 59 76 n
        _ -> False
    ("hcl:", v) ->
      T.take 1 v == "#" && (T.length v, T.length (T.filter (`elem` ("0123456789abcdef"::String)) (T.drop 1 v))) == (7, 6)
    ("ecl:", v) -> v `elem` (T.splitOn " " "amb blu brn gry grn hzl oth")
    ("pid:", v) -> (T.length v, T.length (T.filter C.isDigit v)) == (9, 9)
    _ -> True

main = do
  text <- TIO.readFile "./d4.txt"
  print $ length $ filter (all isValidField) $ passportTexts text

p2.js

const Joi = require('joi');

const validateHeight = (value, helpers) => {
    if (!value.constructor || value.constructor !== String || !(value.endsWith('in') || value.endsWith('cm'))) {
        return helpers.error('Expected string ending in cm or in');
    }

    const v = value.slice(0, -2);

    let min = 150, max = 193;

    if (value.endsWith('in')) {
        min = 59;
        max = 76;
    }

    const { error } = Joi.number().integer().min(min).max(max).validate(v);

    if (error) {
        return helpers.error(error);
    }

    return value;
};

const gregYearStrBetween = (start, end) =>
    Joi.number()
      .integer()
      .min(start)
      .max(end)
      .required();

const schema = Joi.object({
    byr: gregYearStrBetween(1920, 2002),

    iyr: gregYearStrBetween(2010, 2020),

    eyr: gregYearStrBetween(2020, 2030),

    hgt: Joi.any()
        .custom(validateHeight, 'height')
        .required(),

    hcl: Joi.string()
        .pattern(/^#[0-9a-f]{6}$/)
        .required(),

    ecl: Joi.any()
        .allow('amb', 'blu', 'brn', 'gry', 'grn', 'hzl', 'oth')
        .only()
        .required(),

    pid: Joi.string()
        .pattern(/^[0-9]{9}$/)
        .required(),

    cid: Joi.any()
});

const passports = require('./d4.json');

console.log(passports.filter((p, i) => !schema.validate(p).error).length);

https://gist.github.com/mjgpy3/5912813d5b2e17ebf53b933205702683#file-p2-js-L20 had a horrible error to debug! If you don't call helpers.error just returning error makes the validator pass. I missed strong types there.