module ApiMe

# File lib/api_me.rb, line 128
def create
  @object = build_resource
  authorize_resource @object
  create_resource!

  render status: :created, json: @object, root: singular_root_key, serializer: serializer_klass
end

# File lib/api_me.rb, line 149
def destroy
  @object = find_resource
  authorize_resource @object
  destroy_resource!

  head :no_content
end

# File lib/api_me.rb, line 136
def edit
  render_errors(['edit endpoint not supported'], :not_found)
end

# File lib/api_me.rb, line 76
def index
  @policy_scope = policy_scope(resource_scope)
  @filter_scope = filter_scope(@policy_scope)
  @sorted_scope = sort_scope(@filter_scope)
  @pagination_object = paginate_scope(@sorted_scope, page_params)

  respond_to do |format|
    format.csv do
      @csv_includes_scope = csv_includes_scope(@sorted_scope)
      response.headers['Content-Type'] = 'text/csv'
      response.headers['Cache-Control'] = 'no-cache'
      # Hack to work around https://github.com/rack/rack/issues/1619
      response.headers['Last-Modified'] = Time.current.httpdate
      # Disable gzip in nginx
      response.headers['X-Accel-Buffering'] = 'no'
      response.headers['Content-Disposition'] = "attachment; filename=\"#{csv_filename}\""

      ::ApiMe::CsvStreamWriter.generate(response.stream) do |csv|
        # headers
        csv << csv_headers
        @csv_includes_scope.find_each do |object|
          csv << object.try('to_csv')
        end
      end
    ensure
      response.stream.close
    end
    format.all do
      render(
        json: @pagination_object.results,
        root: collection_root_key,
        each_serializer: serializer_klass,
        meta: {
          page: @pagination_object.page_meta,
          sort: sorting_meta(@filter_scope)
        }
      )
    end
  end
end

# File lib/api_me.rb, line 124
def new
  render_errors(['new endpoint not supported'], :not_found)
end

# File lib/api_me.rb, line 117
def show
  @object = find_resource
  authorize_resource @object

  render json: @object, root: singular_root_key, serializer: serializer_klass
end

# File lib/api_me.rb, line 140
def update
  @object = find_resource
  @object.assign_attributes(object_params)
  authorize_resource @object
  update_resource!

  render status: :ok, json: @object, root: singular_root_key, serializer: serializer_klass
end

# File lib/api_me.rb, line 288
def authorize_resource(resource)
  authorize resource
end

# File lib/api_me.rb, line 272
def build_resource
  @build_resource ||= model_klass.new(object_params)
end

# File lib/api_me.rb, line 175
def collection_root_key
  model_klass.name.pluralize.underscore
end

# File lib/api_me.rb, line 276
def create_resource!
  @object.save!
end

# File lib/api_me.rb, line 159
def csv_filename
  "#{model_klass.name.dasherize}-#{Time.zone.now.to_date.to_s(:default)}.csv"
end

# File lib/api_me.rb, line 163
def csv_headers
  model_klass.respond_to?('csv_headers') ? model_klass.csv_headers : []
end

# File lib/api_me.rb, line 167
def csv_includes_scope(scope)
  scope
end

# File lib/api_me.rb, line 284
def destroy_resource!
  @object.destroy!
end

# File lib/api_me.rb, line 218
def filter_klass
  self.class.filter_klass
end

# File lib/api_me.rb, line 264
def filter_params
  params[:filters]
end

# File lib/api_me.rb, line 230
def filter_scope(scope)
  filter_klass.new(
    scope: scope,
    filters: filters_hash
  ).results
end

# File lib/api_me.rb, line 259
def filters_hash
  ids_filter_hash = params[:ids] ? { ids: params[:ids] } : {}
  (filter_params || {}).merge(ids_filter_hash)
end

# File lib/api_me.rb, line 268
def find_resource
  @find_resource ||= model_klass.find_by!(id: params[:id])
end

# File lib/api_me.rb, line 195
def handle_active_record_errors(active_record_error)
  Rails.logger.debug "ERROR: #{active_record_error}"
  render_errors(active_record_error.record.errors.messages)
end

# File lib/api_me.rb, line 210
def model_klass
  self.class.model_klass
end

# File lib/api_me.rb, line 179
def object_params
  params.require(params_klass_symbol).permit(*policy(@object || model_klass).permitted_attributes)
end

# File lib/api_me.rb, line 183
def page_params
  params[:page]
end

# File lib/api_me.rb, line 251
def paginate_scope(scope, params)
  ApiMe::Pagination.new(scope: scope, page_params: params)
end

# File lib/api_me.rb, line 255
def params_klass_symbol
  model_klass.name.demodulize.underscore.to_sym
end

# File lib/api_me.rb, line 191
def render_errors(errors, status = :unprocessable_entity)
  render(json: { errors: errors }, status: status)
end

# File lib/api_me.rb, line 206
def resource_not_found
  head :not_found
end

# File lib/api_me.rb, line 226
def resource_scope
  model_klass.all
end

# File lib/api_me.rb, line 214
def serializer_klass
  self.class.serializer_klass
end

# File lib/api_me.rb, line 171
def singular_root_key
  model_klass.name.singularize.underscore
end

# File lib/api_me.rb, line 222
def sort_klass
  ApiMe::Sorting
end

# File lib/api_me.rb, line 187
def sort_params
  params[:sort]
end

# File lib/api_me.rb, line 244
def sort_scope(scope, sortable_params = sort_params)
  sort_klass.new(
    scope: scope,
    sort_params: sortable_params
  ).results
end

# File lib/api_me.rb, line 237
def sorting_meta(scope, sortable_params = sort_params)
  sort_klass.new(
    scope: scope,
    sort_params: sortable_params
  ).sort_meta
end

# File lib/api_me.rb, line 280
def update_resource!
  @object.save!
end

# File lib/api_me.rb, line 201
def user_not_authorized
  payload = { message: "User is not allowed to access #{params[:action]} on this resource" }
  render json: payload, status: :forbidden
end