# Formats output to a bold, green text
def puts(*) # Formats output
  print("\e[1m\e[32m") # formats text to bold, green
  super
  print("\e[22m\e[0m") # clear format
end

# Outputs error message and exits program with failure(1)
def fail(message) 
  Kernel.puts "\e[1m\e[31m#{message}\e[22m\e[0m" # bold, red
  exit false
end

puts '$ git fetch --all'
system 'git fetch --all'

default_branch = 'master'
current_branch = `git rev-parse --abbrev-ref HEAD`.strip
input_branch = ARGV[0]
target_branch = input_branch || default_branch

if input_branch
  `git show-ref #{input_branch}`
  fail('Input Branch not found') if $?.exitstatus == 1
end

puts "Finding Diff migrations between" \
  "\n\tCurrent -> #{current_branch}" \
  "\n\tTarget  -> #{target_branch}"

migrations = `git diff #{target_branch} --name-status | egrep db/migrate`

migrations = migrations.split("\n").map{ |str| str.delete_prefix("A\tdb/migrate/") }

if migrations.any?
  puts
  migrations.each { |migration| puts "  #{migration}" }
  puts

  puts 'Rollbacking "LIFO"...'

  migrations.reverse.each do |migration|
    version = migration.gsub(/[^\d]/, '')
    
    `bundle exec rake db:migrate:down VERSION=#{version}`
    puts "#{version} Down."
  end
  
  puts 'Rollback Done.'

  `git restore db/schema.rb`
else
  puts 'No migrations to rollback.'
end

puts "Checking out to #{target_branch}..."

puts "$ git checkout #{target_branch}"
`git checkout #{target_branch}`

fail('Checkout failed. Please check error message above.') if $?.exitstatus == 1

puts "Done."