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

require 'rubocop'

file = ARGV[0]

unless file
  warn('Error: missing file, please supply one')
  abort
end

# Taken from https://github.com/rubocop/rubocop/blob/v0.93.1/lib/rubocop/result_cache.rb#L159-L171
def file_checksum(file, config_store)
  digester = Digest::SHA1.new
  mode = File.stat(file).mode

  puts "mode of #{file} is #{mode}"
  puts "signature of #{file} is #{config_store.for_file(file).signature}"
  puts "config is:"
  puts config_store.for_file(file).to_h

  digester.update(
    "#{file}#{mode}#{config_store.for_file(file).signature}"
  )
  digester.file(file)
  digester.hexdigest
rescue Errno::ENOENT
  # Spurious files that come and go should not cause a crash, at least not
  # here.
  '_'
end

config_store = RuboCop::ConfigStore.new
checksum = file_checksum(file, config_store)
puts "File checksum for #{file} is #{checksum}"