Creating a factorial hash of variants of a product to JS in Spree

product_variants.rb

def product_variants
  products = Spree::Taxon.find_by(name: 'Donations').products
  product_hash = {}

  variants = -> (product) do
    variant_hash = {}

    option_values = -> (option_type) do
      option_value_hash = {}

      option_type.option_values.each do |option_value|
        option_value_variants = option_value.variants.to_a.keep_if do |variant|
          variant.product.id == product.id
        end

        option_value_hash[option_value.name] = option_value_variants.map(&:gon_object)
      end

      option_value_hash
    end

    product.option_types.each_with_index do |option_type, index|
      variant_hash[option_type.name] = option_values.call(option_type)
    end

    variant_hash
  end
  
  products.each do |product|
    product_hash[product.id] = variants.call(product)
  end
  
  product_hash
end


# You would access these through a Rails-to-JS data window such as Gon.
# > gon
#   Object {variants: Object}

# You would be able to set your variants via `gon.variants = Spree::Product.product_variants` in your controller.
# This would give you this result in the console (assuming that you have 8 products.
# > gon.variants
#   Object {1: Object, 2: Object, 3: Object, 4: Object, 5: Object, 6: Object, 7: Object, 8: Object}

# We access the variants of a product through the ID of the product. This gives us a listing of all the option types.
# > gon.variants['1']
#   Object {goodie-options: Object, share-name: Object}

# After we have asked for the option types, we see a list of the option values
# > gon.variants['1']['goodie-options']
#   Object {yes: Array[2], no: Array[2]}

# Once inside of the option value, we see an array of objects which are variants
# > gon.variants['1']['goodie-options']['yes']
#   [Object, Object]

# And here's the variant:
# > gon.variants['1']['goodie-options']['yes'][0]
#   Object {sku: "123489", weight: 0, height: 0, width: 0, depth: 0…}

# There will need to be a comparison of the variants between the option values selected.