# Based on discussion in https://github.com/rails/rails/pull/23712#issuecomment-184977238,
# the JSON API media type will have its own format/renderer.
#
# > We recommend the media type be registered on its own as jsonapi
# when a jsonapi Renderer and deserializer (Http::Parameters::DEFAULT_PARSERS) are added.
#
# Usage:
#
# ActiveSupport.on_load(:action_controller) do
#   require 'active_model_serializers/register_jsonapi_renderer'
# end
#
# And then in controllers, use `render jsonapi: model` rather than `render json: model, adapter: :json_api`.
#
# For example, in a controller action, we can:
# respond_to do |format|
#   format.jsonapi { render jsonapi: model }
# end
#
# or
#
# render jsonapi: model
#
# No wrapper format needed as it does not apply (i.e. no `wrap_parameters format: [jsonapi]`)

module ActiveModelSerializers::Jsonapi
  MEDIA_TYPE = 'application/vnd.api+json'.freeze
  HEADERS = {
    response: { 'CONTENT_TYPE'.freeze => MEDIA_TYPE },
    request:  { 'ACCEPT'.freeze => MEDIA_TYPE }
  }.freeze
  module ControllerSupport
    def serialize_jsonapi(json, options)
      options[:adapter] = :json_api
      options.fetch(:serialization_context) { options[:serialization_context] = ActiveModelSerializers::SerializationContext.new(request) }
      get_serializer(json, options)
    end
  end
end

# actionpack/lib/action_dispatch/http/mime_types.rb
Mime::Type.register ActiveModelSerializers::Jsonapi::MEDIA_TYPE, :jsonapi

parsers = Rails::VERSION::MAJOR >= 5 ? ActionDispatch::Http::Parameters : ActionDispatch::ParamsParser
media_type = Mime::Type.lookup(ActiveModelSerializers::Jsonapi::MEDIA_TYPE)

# Proposal: should actually deserialize the JSON API params
# to the hash format expected by `ActiveModel::Serializers::JSON`
# actionpack/lib/action_dispatch/http/parameters.rb
parsers::DEFAULT_PARSERS[media_type] = lambda do |body|
  data = JSON.parse(body)
  data = { :_json => data } unless data.is_a?(Hash)
  data.with_indifferent_access
end

# ref https://github.com/rails/rails/pull/21496
ActionController::Renderers.add :jsonapi do |json, options|
  json = serialize_jsonapi(json, options).to_json(options) unless json.is_a?(String)
  self.content_type ||= media_type
  self.response_body = json
end

ActiveSupport.on_load(:action_controller) do
  include ActiveModelSerializers::Jsonapi::ControllerSupport
end