module Semian::Adapter

def acquire_semian_resource(scope:, adapter:, &block)
  return yield if resource_already_acquired?
  semian_resource.acquire(scope: scope, adapter: adapter, resource: self) do
    mark_resource_as_acquired(&block)
  end
rescue ::Semian::OpenCircuitError => error
  last_error = semian_resource.circuit_breaker.last_error
  message = "#{error.message} caused by #{last_error.message}"
  last_error = nil unless last_error.is_a?(Exception) # Net::HTTPServerError is not an exception
  raise self.class::CircuitOpenError.new(semian_identifier, message), cause: last_error
rescue ::Semian::BaseError => error
  raise self.class::ResourceBusyError.new(semian_identifier, error.message)
rescue *resource_exceptions => error
  error.semian_identifier = semian_identifier if error.respond_to?(:semian_identifier=)
  raise
end

def clear_semian_resource
  @semian_resource = nil
end

def mark_resource_as_acquired
  previous = @resource_acquired
  @resource_acquired = true
  yield
ensure
  @resource_acquired = previous
end

def raw_semian_options
  raise NotImplementedError, "Semian adapters must implement a `raw_semian_options` method"
end

def resource_already_acquired?
  @resource_acquired
end

def resource_exceptions
  raise NotImplementedError, "Semian adapters must implement a `resource_exceptions` method"
end

def semian_identifier
  raise NotImplementedError, "Semian adapters must implement a `semian_identifier` method"
end

def semian_options
  return @semian_options if defined? @semian_options
  options = raw_semian_options
  @semian_options = options && options.map { |k, v| [k.to_sym, v] }.to_h
end

def semian_resource
  @semian_resource ||= case semian_options
  when false
    UnprotectedResource.new(semian_identifier)
  when nil
    Semian.logger.info("Semian is not configured for #{self.class.name}: #{semian_identifier}")
    UnprotectedResource.new(semian_identifier)
  else
    options = semian_options.dup
    options.delete(:name)
    options[:consumer] = self
    options[:exceptions] ||= []
    options[:exceptions] += resource_exceptions
    ::Semian.retrieve_or_register(semian_identifier, **options)
  end
end