# frozen_string_literal: true

module Katalyst
  module Tables
    module Collection
      module Type
        class Value < ActiveModel::Type::Value
          using Helpers::Extensions

          attr_reader :scope

          def initialize(scope: nil, filter: true)
            super()

            @scope = scope
            @filterable = filter
          end

          def filterable?
            @filterable
          end

          def filter?(attribute, value)
            return false unless filterable?

            if attribute.came_from_user?
              attribute.value_before_type_cast.present?
            else
              value.present?
            end
          end

          def filter(scope, attribute)
            value = filter_value(attribute)

            return scope unless filter?(attribute, value)

            scope, model, column = model_and_column_for(scope, attribute)
            condition = filter_condition(model, column, value)

            scope.merge(condition)
          end

          def examples_for(scope, attribute)
            scope, model, column = model_and_column_for(scope, attribute)

            return unless model.attribute_types.has_key?(column)

            column = model.arel_table[column]

            filter(scope, attribute)
              .group(column)
              .distinct
              .limit(10)
              .reorder(column => :asc)
              .pluck(column)
              .map { |v| serialize(v) }
          end

          private

          def filter_value(attribute)
            attribute.value
          end

          def filter_condition(model, column, value)
            if value.nil?
              model.none
            elsif scope
              model.public_send(scope, value)
            else
              model.where(column => value)
            end
          end

          def model_and_column_for(scope, attribute)
            if attribute.name.include?(".")
              table, column = attribute.name.split(".")
              [scope.joins(table.to_sym), scope.model.reflections[table].klass, column]
            else
              [scope, scope.model, attribute.name]
            end
          end
        end
      end
    end
  end
end