module Bootsnap::CompileCache::YAML

def init!
  require('yaml')
  require('msgpack')
  # MessagePack serializes symbols as strings by default.
  # We want them to roundtrip cleanly, so we use a custom factory.
  # see: https://github.com/msgpack/msgpack-ruby/pull/122
  factory = MessagePack::Factory.new
  factory.register_type(0x00, Symbol)
  self.msgpack_factory = factory
  self.supported_options = []
  params = ::YAML.method(:load).parameters
  if params.include?([:key, :symbolize_names])
    self.supported_options << :symbolize_names
  end
  if params.include?([:key, :freeze])
    if factory.load(factory.dump('yaml'), freeze: true).frozen?
      self.supported_options << :freeze
    end
  end
  self.supported_options.freeze
end

def input_to_output(data, kwargs)
  ::YAML.load(data, **(kwargs || {}))
end

def input_to_storage(contents, _, kwargs)
  raise(Uncompilable) if contents.index("!ruby/object")
  obj = ::YAML.load(contents, **(kwargs || {}))
  msgpack_factory.dump(obj)
rescue NoMethodError, RangeError
  # if the object included things that we can't serialize, fall back to
  # Marshal. It's a bit slower, but can encode anything yaml can.
  # NoMethodError is unexpected types; RangeError is Bignums
  Marshal.dump(obj)
end

def install!(cache_dir)
  self.cache_dir = cache_dir
  init!
  ::YAML.singleton_class.prepend(Patch)
end

def storage_to_output(data, kwargs)
  # This could have a meaning in messagepack, and we're being a little lazy
  # about it. -- but a leading 0x04 would indicate the contents of the YAML
  # is a positive integer, which is rare, to say the least.
  if data[0] == 0x04.chr && data[1] == 0x08.chr
    Marshal.load(data)
  else
    msgpack_factory.load(data, **(kwargs || {}))
  end
end