#!/usr/bin/env ruby
# frozen_string_literal: true

require "json"
require "open-uri"
require "optparse"
require "tmpdir"

# Options
ARGV.push("--help") if ARGV.empty?

OptionParser.new do |opt|
  opt.banner = <<~BANNER
    Run `brew` `audit` and `style` checks locally, from a pull request URL.
    Useful when online CI is broken.

    Usage:
      #{File.basename($PROGRAM_NAME)} <pr url>

    Options:
  BANNER

  opt.on("-h", "--help", "Show this help.") do
    puts opt
    exit 0
  end
end.parse!

pr_url = ARGV[0]

unless %r{^https://github.com/Homebrew/homebrew-cask.*}.match?(pr_url)
  abort "URL is not from an official Homebrew Cask tap"
end

pr_api = pr_url.sub(%r{^https://github.com/([^/]+)/([^/]+)/pull/([^/]+).*},
                    'https://api.github.com/repos/\1/\2/pulls/\3/files')
pr_json = JSON.parse(URI(pr_api).read)

abort "PR needs to have a single file" if pr_json.count != 1

file_raw_url = pr_json[0]["raw_url"].gsub("%2F", "/")
file_name = File.basename(file_raw_url)
local_file = File.join(Dir.mktmpdir, file_name)

File.write(local_file, URI(file_raw_url).read)
abort "Audit failed" unless system("brew", "audit", "--new", local_file)
abort "Style check failed" unless system("brew", "style", local_file)
