From 5cd7380d29ce0d7b35eeaa2ef51e9323695064be Mon Sep 17 00:00:00 2001
From: Anton Katunin <antulik@gmail.com>
Date: Tue, 9 Jul 2024 12:57:51 +1000
Subject: [PATCH] Nested attributes extension

---
 lib/active_interaction/extras.rb              |  1 +
 lib/active_interaction/extras/all.rb          |  1 +
 .../extras/nested_attributes.rb               | 76 +++++++++++++++++++
 .../extras/strong_params.rb                   | 51 ++++++++++---
 4 files changed, 118 insertions(+), 11 deletions(-)
 create mode 100644 lib/active_interaction/extras/nested_attributes.rb

diff --git a/lib/active_interaction/extras.rb b/lib/active_interaction/extras.rb
index 90356bf..2093c77 100644
--- a/lib/active_interaction/extras.rb
+++ b/lib/active_interaction/extras.rb
@@ -23,6 +23,7 @@ module Jobs
     autoload(:FilterAlias, "active_interaction/extras/filter_alias")
     autoload(:Halt, "active_interaction/extras/halt")
     autoload(:ModelFields, "active_interaction/extras/model_fields")
+    autoload(:NestedAttributes, "active_interaction/extras/nested_attributes")
     autoload(:RunCallback, "active_interaction/extras/run_callback")
     autoload(:StrongParams, "active_interaction/extras/strong_params")
     autoload(:Transaction, "active_interaction/extras/transaction")
diff --git a/lib/active_interaction/extras/all.rb b/lib/active_interaction/extras/all.rb
index bf67dfa..ca299e4 100644
--- a/lib/active_interaction/extras/all.rb
+++ b/lib/active_interaction/extras/all.rb
@@ -7,6 +7,7 @@ module ActiveInteraction::Extras::All
   include ActiveInteraction::Extras::FilterAlias
   include ActiveInteraction::Extras::Halt
   include ActiveInteraction::Extras::ModelFields
+  include ActiveInteraction::Extras::NestedAttributes
   include ActiveInteraction::Extras::RunCallback
   include ActiveInteraction::Extras::StrongParams
 
diff --git a/lib/active_interaction/extras/nested_attributes.rb b/lib/active_interaction/extras/nested_attributes.rb
new file mode 100644
index 0000000..edc6fbd
--- /dev/null
+++ b/lib/active_interaction/extras/nested_attributes.rb
@@ -0,0 +1,76 @@
+# inspired by store_model/nested_attributes.rb
+module ActiveInteraction::Extras::NestedAttributes
+  extend ActiveSupport::Concern
+
+  concern :InputsExtension do
+    def normalize(inputs)
+      @base.class.nested_attribute_options.each do |attribute, options|
+        alias_name = "#{attribute}_attributes"
+        next if !inputs.key?(alias_name) && !inputs.key?(alias_name.to_sym)
+
+        value = inputs[alias_name] || inputs[alias_name.to_sym]
+        value = @base.class.process_nested_collection(value, options)
+
+        inputs[attribute.to_s] = value
+      end
+
+      super
+    end
+  end
+
+  included do
+    ActiveInteraction::Inputs.prepend InputsExtension
+
+    class_attribute :nested_attribute_options, default: {}
+  end
+
+  class_methods do
+    def accepts_nested_attributes_for(*attributes)
+      options = attributes.extract_options!
+      options.reverse_merge!(allow_destroy: false, update_only: false)
+
+      attributes.each do |attribute|
+        nested_attribute_options[attribute] = options
+
+        case filters[attribute]
+        when ActiveInteraction::ArrayFilter
+          define_association_setter_for_many attribute, options
+        else
+          raise "Nested attributes are not supported for single object"
+        end
+      end
+    end
+
+    def define_association_setter_for_many(association, options)
+      define_method "#{association}_attributes=" do |attributes|
+        attributes = self.class.process_nested_collection(attributes, options)
+        send("#{association}=", attributes)
+      end
+    end
+
+    def process_nested_collection(attributes, options = nil)
+      attributes = attributes.values if attributes.is_a?(Hash)
+
+      if options&.dig(:allow_destroy)
+        attributes.reject! do |attribute|
+          ActiveRecord::Type::Boolean.new.cast(attribute.stringify_keys.dig("_destroy"))
+        end
+      end
+
+      attributes.reject! { |attribute| call_reject_if(attribute, options[:reject_if]) } if options&.dig(:reject_if)
+
+      attributes
+    end
+
+    def call_reject_if(attributes, callback)
+      callback = ActiveRecord::NestedAttributes::ClassMethods::REJECT_ALL_BLANK_PROC if callback == :all_blank
+
+      case callback
+      when Symbol
+        method(callback).arity.zero? ? send(callback) : send(callback, attributes)
+      when Proc
+        callback.call(attributes)
+      end
+    end
+  end
+end
diff --git a/lib/active_interaction/extras/strong_params.rb b/lib/active_interaction/extras/strong_params.rb
index e2130e3..81ebea1 100644
--- a/lib/active_interaction/extras/strong_params.rb
+++ b/lib/active_interaction/extras/strong_params.rb
@@ -29,18 +29,47 @@ def initialize(inputs = {})
 
   class_methods do
     def permitted_params
-      filters.map do |filter_name, filter|
-        next unless filter.options[:permit]
-
-        case filter
-        when ActiveInteraction::ArrayFilter
-          { filter_name => [] }
-        when ActiveInteraction::HashFilter, ActiveInteraction::ObjectFilter
-          { filter_name => {} }
-        else
-          filter_name
+      permissions = filters.map do |filter_name, filter|
+        [
+          permission_for_filter(filter, filter_name),
+          # (permission_for_filter(filter, filter.options[:as]) if filter.options[:as])
+        ]
+      end.flatten(1).compact
+
+      if respond_to?(:nested_attribute_options)
+        nested_attribute_options.each do |attribute, _|
+          permissions << {"#{attribute}_attributes": {}}
         end
-      end.compact
+      end
+
+      permissions
+    end
+
+    def permission_for_filter(filter, name = filter.name)
+      permit = filter.options[:permit]
+      return unless permit
+
+      case filter
+      when ActiveInteraction::ArrayFilter
+        value =
+          if permit == true
+            nested_type = filter.filters.values.first
+            case nested_type
+            when ActiveInteraction::HashFilter, ActiveInteraction::ObjectFilter
+              {}
+            else
+              []
+            end
+          else
+            permit
+          end
+
+        { name => value }
+      when ActiveInteraction::HashFilter, ActiveInteraction::ObjectFilter
+        { name => {} }
+      else
+        name
+      end
     end
   end
 end