fetch_puzzle

#!/usr/bin/env ruby
require 'open3'
require 'httparty'

raise "Missing day" unless ARGV[0] =~ /[0-9]+/
day = ARGV[0]
raise "Missing session" unless ARGV[1] =~ /[a-z0-9]+/
session = ARGV[1]
# query previous year puzzle if we are not in december yet
year = ARGV[2] || (Time.now.year - (Time.now.month < 12 ? 1 : 0)).to_s

headers = {
  "Host": "adventofcode.com",
  "User-Agent": "Mozilla/5.0 (X11; Linux x86_64; rv:133.0) Gecko/20100101 Firefox/133.0",
  "Accept": "text/html,application/xhtml+xml,application/xml;q=0.9,*/*;q=0.8",
  "Accept-Language": "en-US,en;q=0.5",
  "Accept-Encoding": "gzip, deflate, br, zstd",
  "Referer": "https://adventofcode.com/",
  "Connection": "keep-alive",
  "Cookie": "session=#{session}",
  "Upgrade-Insecure-Requests": "1",
  "Sec-Fetch-Dest": "document",
  "Sec-Fetch-Mode": "navigate",
  "Sec-Fetch-Site": "same-origin",
  "Sec-Fetch-User": "?1",
  "Priority": "u=0, i",
}

# attempt to read puzzle
url = "https://adventofcode.com/#{year}/day/#{day}"
response = HTTParty.get(url, headers: headers)
raise response unless response.code == 200
begin
  stdin, stdout, stderr, wait_thr = Open3.popen3("pandoc --from html --to markdown_strict")
  stdin.write response.body
  stdin.close
  # Read and print output from the Ruby file
  puts stdout.read
end