class Jets::Builders::CodeSize

def self.check!
  new.check
end

def check
  return if within_lambda_limit?
  say "Over the Lambda size limit of #{LAMBDA_SIZE_LIMIT}MB".color(:red)
  say "Please reduce the size of your code."
  display_sizes
  exit 1
end

def compute_size(path)
  # -k option is required for macosx but not for linux
  out = `du -ks #{path}`
  out.split(' ').first.to_i # bytes
end

def display_sizes
  code_size = compute_size("#{stage_area}/code")
  opt_size = compute_size("#{stage_area}/opt")
  total_size = opt_size + code_size
  overlimit = (LAMBDA_SIZE_LIMIT * 1024 - total_size) * -1
  say "Sizes:"
  say "Code: #{megabytes(code_size)} - #{stage_area}/code"
  say "Gem Layer: #{megabytes(opt_size)} - #{stage_area}/opt"
  say "Total Package: #{megabytes(total_size)}"
  say "Over limit by: #{megabytes(overlimit)}"
  say "Sometimes blowing away the /tmp/jets cache will reduce the size: rm -rf /tmp/jets"
  # sh "du -kcsh #{stage_area}/*" unless ENV['TEST'] # uncomment to debug
end

def megabytes(bytes)
  n = bytes / 1024.0
  sprintf('%.1f', n) + 'MB'
end

def say(message)
  puts message unless ENV['TEST']
end

def total_size
  code_size = compute_size("#{stage_area}/code")
  opt_size = compute_size("#{stage_area}/opt")
  opt_size + code_size # total_size
end

def within_lambda_limit?
  total_size < LAMBDA_SIZE_LIMIT * 1024 # 120MB
end