Add problem downloader

.gitignore

@@ -0,0 +1 @@
+tmp/

Gemfile

@@ -1,3 +1,5 @@
 source "https://rubygems.org"
 
+gem "nokogiri"
 gem "rspec"
+gem "watir"

Gemfile.lock

@@ -1,7 +1,18 @@
 GEM
   remote: https://rubygems.org/
   specs:
+    base64 (0.2.0)
     diff-lcs (1.5.1)
+    logger (1.6.2)
+    mini_portile2 (2.8.8)
+    nokogiri (1.17.1)
+      mini_portile2 (~> 2.8.2)
+      racc (~> 1.4)
+    nokogiri (1.17.1-arm64-darwin)
+      racc (~> 1.4)
+    racc (1.8.1)
+    regexp_parser (2.9.3)
+    rexml (3.3.9)
     rspec (3.13.0)
       rspec-core (~> 3.13.0)
       rspec-expectations (~> 3.13.0)
@@ -15,13 +26,26 @@ GEM
       diff-lcs (>= 1.2.0, < 2.0)
       rspec-support (~> 3.13.0)
     rspec-support (3.13.2)
+    rubyzip (2.3.2)
+    selenium-webdriver (4.27.0)
+      base64 (~> 0.2)
+      logger (~> 1.4)
+      rexml (~> 3.2, >= 3.2.5)
+      rubyzip (>= 1.2.2, < 3.0)
+      websocket (~> 1.0)
+    watir (7.3.0)
+      regexp_parser (>= 1.2, < 3)
+      selenium-webdriver (~> 4.2)
+    websocket (1.2.11)
 
 PLATFORMS
   arm64-darwin-24
   ruby
 
 DEPENDENCIES
+  nokogiri
   rspec
+  watir
 
 BUNDLED WITH
    2.5.23

download-problems

@@ -0,0 +1,65 @@
+#!/usr/bin/env ruby
+
+require "fileutils"
+require "html2markdown"
+require "nokogiri"
+require "watir"
+require "debug"
+
+browser = Watir::Browser.new(:chrome, headless: true)
+
+def login(browser)
+  browser.goto("https://adventofcode.com/auth/github")
+
+  browser.text_field(name: "login").set(ENV.fetch("GITHUB_USERNAME"))
+  browser.text_field(name: "password").set(ENV.fetch("GITHUB_PASSWORD"))
+  browser.button(name: "commit").click
+
+  code = browser.text.scan(/Enter the digits shown below to verify your identity.\n(\d+)/)
+
+  if browser.url.include?("two-factor")
+    puts "Complete 2FA on phone. Code: #{code}"
+
+    Watir::Wait.until(timeout: 120) do
+      !browser.url.include?("two-factor")
+    end
+  end
+
+  if browser.button(name: "authorize").exists?
+    browser.button(name: "authorize").click
+  end
+
+  final_url = browser.url
+  browser.goto(final_url)
+
+  session_cookies = browser.cookies.to_a
+  File.write("tmp/cookies.json", session_cookies.to_json)
+
+  browser.close
+end
+
+local = Dir
+  .entries(".")
+  .select { |entry| File.directory?(entry) && !entry.match?(/^\./) }
+
+browser.goto("https://adventofcode.com/")
+cookies = JSON.parse(File.read("tmp/cookies.json"))
+cookies.each { |cookie| browser.cookies.add(cookie["name"], cookie["value"], domain: cookie["domain"]) }
+pre_element = browser.element(tag_name: "pre", class: "calendar")
+doc = Nokogiri::HTML(pre_element.html)
+links = doc.css("a").map { |link| link["href"] }
+
+available = links.map { _1.scan(/day\/(\d+)/) }.flatten.map { "%02d" % _1 }
+
+missing = available - local
+
+if missing.any?
+  missing.each do |problem|
+    Dir.mkdir(problem)
+    browser.goto("https://adventofcode.com/2024/day/#{problem}/input")
+    File.write("#{problem}/input", browser.text)
+    FileUtils.copy("./template.rb", "./#{problem}/main.rb")
+  end
+else
+  puts "All problems are currently local"
+end

template.rb

@@ -1,7 +1,7 @@
 #!/usr/bin/env ruby
 
 problem = :fake
-#input = File.readlines("#{problem}.input", chomp: true)
+#input = File.readlines("input", chomp: true)
 input = DATA.read
 
 result = :solution