module Spree
  module ProductScopes
    extend ActiveSupport::Concern

    included do
      cattr_accessor :search_scopes do
        []
      end

      def self.add_search_scope(name, &block)
        singleton_class.send(:define_method, name.to_sym, &block)
        search_scopes << name.to_sym
      end

      def self.simple_scopes
        [
          :ascend_by_updated_at,
          :descend_by_updated_at,
          :ascend_by_name,
          :descend_by_name
        ]
      end

      def self.add_simple_scopes(scopes)
        scopes.each do |name|
          # We should not define price scopes here, as they require something slightly different
          next if name.to_s.include?('master_price')

          parts = name.to_s.match(/(.*)_by_(.*)/)
          scope(name.to_s, -> { order(Arel.sql("#{Product.quoted_table_name}.#{parts[2]} #{parts[1] == 'ascend' ? 'ASC' : 'DESC'}")) })
        end
      end

      def self.property_conditions(property)
        properties = Property.table_name
        case property
        when String   then { "#{properties}.name" => property }
        when Property then { "#{properties}.id" => property.id }
        else { "#{properties}.id" => property.to_i }
        end
      end

      add_simple_scopes simple_scopes

      add_search_scope :ascend_by_master_price do
        order("#{price_table_name}.amount ASC")
      end

      add_search_scope :descend_by_master_price do
        order("#{price_table_name}.amount DESC")
      end

      add_search_scope :price_between do |low, high|
        where(Price.table_name => { amount: low..high })
      end

      add_search_scope :master_price_lte do |price|
        where("#{price_table_name}.amount <= ?", price)
      end

      add_search_scope :master_price_gte do |price|
        where("#{price_table_name}.amount >= ?", price)
      end

      # This scope selects products in taxon AND all its descendants
      # If you need products only within one taxon use
      #
      #   Spree::Product.joins(:taxons).where(Taxon.table_name => { id: taxon.id })
      #
      # If you're using count on the result of this scope, you must use the
      # `:distinct` option as well:
      #
      #   Spree::Product.in_taxon(taxon).count(distinct: true)
      #
      # This is so that the count query is distinct'd:
      #
      #   SELECT COUNT(DISTINCT "spree_products"."id") ...
      #
      #   vs.
      #
      #   SELECT COUNT(*) ...
      add_search_scope :in_taxon do |taxon|
        includes(:classifications).
          where('spree_products_taxons.taxon_id' => taxon.cached_self_and_descendants_ids).
          order('spree_products_taxons.position ASC')
      end

      # This scope selects products in all taxons AND all its descendants
      # If you need products only within one taxon use
      #
      #   Spree::Product.taxons_id_eq([x,y])
      add_search_scope :in_taxons do |*taxons|
        taxons = get_taxons(taxons)
        taxons.first ? prepare_taxon_conditions(taxons) : where(nil)
      end

      add_search_scope :ascend_by_taxons_min_position do |taxon_ids|
        joins(:classifications).
          where(Classification.table_name => { taxon_id: taxon_ids }).
          select(
            [
              "#{Product.table_name}.*",
              "MIN(#{Classification.table_name}.position) AS min_position"
            ].join(', ')
          ).
          group(:id).
          order(min_position: :asc)
      end

      # a scope that finds all products having property specified by name, object or id
      add_search_scope :with_property do |property|
        joins(:properties).where(property_conditions(property))
      end

      # a simple test for product with a certain property-value pairing
      # note that it can test for properties with NULL values, but not for absent values
      add_search_scope :with_property_value do |property, value|
        joins(:properties).
          where("#{ProductProperty.table_name}.value = ?", value).
          where(property_conditions(property))
      end

      add_search_scope :with_property_values do |property_filter_param, property_values|
        joins(product_properties: :property).
          where(Property.table_name => { filter_param: property_filter_param }).
          where(ProductProperty.table_name => { filter_param: property_values.map(&:parameterize) })
      end

      add_search_scope :with_option do |option|
        option_types = OptionType.table_name
        conditions = case option
                     when String     then { "#{option_types}.name" => option }
                     when OptionType then { "#{option_types}.id" => option.id }
                     else { "#{option_types}.id" => option.to_i }
                     end

        joins(:option_types).where(conditions)
      end

      add_search_scope :with_option_value do |option, value|
        option_values = OptionValue.table_name
        option_type_id = case option
                         when String then OptionType.find_by(name: option) || option.to_i
                         when OptionType then option.id
                         else option.to_i
                         end

        conditions = "#{option_values}.name = ? AND #{option_values}.option_type_id = ?", value, option_type_id
        group('spree_products.id').joins(variants_including_master: :option_values).where(conditions)
      end

      # Finds all products which have either:
      # 1) have an option value with the name matching the one given
      # 2) have a product property with a value matching the one given
      add_search_scope :with do |value|
        includes(variants_including_master: :option_values).
          includes(:product_properties).
          where("#{OptionValue.table_name}.name = ? OR #{ProductProperty.table_name}.value = ?", value, value)
      end

      # Finds all products that have a name containing the given words.
      add_search_scope :in_name do |words|
        like_any([:name], prepare_words(words))
      end

      # Finds all products that have a name or meta_keywords containing the given words.
      add_search_scope :in_name_or_keywords do |words|
        like_any([:name, :meta_keywords], prepare_words(words))
      end

      # Finds all products that have a name, description, meta_description or meta_keywords containing the given keywords.
      add_search_scope :in_name_or_description do |words|
        like_any([:name, :description, :meta_description, :meta_keywords], prepare_words(words))
      end

      # Finds all products that have the ids matching the given collection of ids.
      # Alternatively, you could use find(collection_of_ids), but that would raise an exception if one product couldn't be found
      add_search_scope :with_ids do |*ids|
        where(id: ids)
      end

      # Sorts products from most popular (popularity is extracted from how many
      # times use has put product in cart, not completed orders)
      #
      # there is alternative faster and more elegant solution, it has small drawback though,
      # it doesn stack with other scopes :/
      #
      # joins: "LEFT OUTER JOIN (SELECT line_items.variant_id as vid, COUNT(*) as cnt FROM line_items GROUP BY line_items.variant_id) AS popularity_count ON variants.id = vid",
      # order: 'COALESCE(cnt, 0) DESC'
      add_search_scope :descend_by_popularity do
        joins(:master).
          order(%Q{
             COALESCE((
               SELECT
                 COUNT(#{LineItem.quoted_table_name}.id)
               FROM
                 #{LineItem.quoted_table_name}
               JOIN
                 #{Variant.quoted_table_name} AS popular_variants
               ON
                 popular_variants.id = #{LineItem.quoted_table_name}.variant_id
               WHERE
                 popular_variants.product_id = #{Product.quoted_table_name}.id
             ), 0) DESC
          })
      end

      add_search_scope :not_deleted do
        where("#{Product.quoted_table_name}.deleted_at IS NULL or #{Product.quoted_table_name}.deleted_at >= ?", Time.zone.now)
      end

      def self.not_discontinued(only_not_discontinued = true)
        if only_not_discontinued != '0' && only_not_discontinued
          where("#{Product.quoted_table_name}.discontinue_on IS NULL or #{Product.quoted_table_name}.discontinue_on >= ?", Time.zone.now)
        else
          all
        end
      end
      search_scopes << :not_discontinued

      def self.with_currency(currency)
        joins(variants_including_master: :prices).
          where(Price.table_name => { currency: currency.upcase }).
          where.not(Price.table_name => { amount: nil }).
          distinct
      end
      search_scopes << :with_currency

      # Can't use add_search_scope for this as it needs a default argument
      def self.available(available_on = nil, currency = nil)
        available_on ||= Time.current

        scope = not_discontinued.where("#{Product.quoted_table_name}.available_on <= ?", available_on)

        unless Spree::Config.show_products_without_price
          currency ||= Spree::Config[:currency]
          scope = scope.with_currency(currency)
        end

        scope
      end
      search_scopes << :available

      def self.active(currency = nil)
        available(nil, currency)
      end
      search_scopes << :active

      def self.for_filters(currency, taxon: nil)
        scope = active(currency)
        scope = scope.in_taxon(taxon) if taxon.present?
        scope
      end
      search_scopes << :for_filters

      def self.for_user(user = nil)
        if user.try(:has_spree_role?, 'admin')
          with_deleted
        else
          not_deleted.not_discontinued.where("#{Product.quoted_table_name}.available_on <= ?", Time.current)
        end
      end

      add_search_scope :taxons_name_eq do |name|
        group('spree_products.id').joins(:taxons).where(Taxon.arel_table[:name].eq(name))
      end

      def self.price_table_name
        Price.quoted_table_name
      end
      private_class_method :price_table_name

      # specifically avoid having an order for taxon search (conflicts with main order)
      def self.prepare_taxon_conditions(taxons)
        ids = taxons.map(&:cached_self_and_descendants_ids).flatten.uniq
        joins(:classifications).where(Classification.table_name => { taxon_id: ids })
      end
      private_class_method :prepare_taxon_conditions

      # Produce an array of keywords for use in scopes.
      # Always return array with at least an empty string to avoid SQL errors
      def self.prepare_words(words)
        return [''] if words.blank?

        a = words.split(/[,\s]/).map(&:strip)
        a.any? ? a : ['']
      end
      private_class_method :prepare_words

      def self.get_taxons(*ids_or_records_or_names)
        taxons = Taxon.table_name
        ids_or_records_or_names.flatten.map do |t|
          case t
          when Integer then Taxon.find_by(id: t)
          when ApplicationRecord then t
          when String
            Taxon.find_by(name: t) ||
              Taxon.where("#{taxons}.permalink LIKE ? OR #{taxons}.permalink = ?", "%/#{t}/", "#{t}/").first
          end
        end.compact.flatten.uniq
      end
      private_class_method :get_taxons
    end
  end
end