module ModelSerializer

# File lib/serializer/model_serializer.rb, line 27
def self.clear_serializer_cache id_or_ids
  if !id_or_ids.is_a?(Array)
    id_or_ids = [id_or_ids]
  end
  id_or_ids.each do |object_id|
    self::SERIALIZER_QUERY_KEYS_CACHE.each do |query_name|
      cache_key = "#{self.name}_____#{query_name}___#{object_id}"
      puts "(class) CLEARING SERIALIZER CACHE: #{cache_key}" if Rails.env.development?
      Rails.cache.delete(cache_key)
    end
  end
end

# File lib/serializer/model_serializer.rb, line 3
def self.included klass
  # START CLASS EVAL
  klass.class_eval do

    # Rails 5 has autoloading issues with modules. They will show as not defined, when available.
    if Rails.env.development?
      begin
        "#{klass.name}Serializer".constantize
      rescue NameError => e
      end
    end
    
    if self.const_defined?("#{klass.name}Serializer")
      serializer_klass = "#{klass.name}Serializer".constantize
      serializer_query_names = serializer_klass.public_instance_methods
      if klass.superclass.const_defined?("SERIALIZER_QUERY_KEYS_CACHE")
        self.const_set('SERIALIZER_QUERY_KEYS_CACHE', (serializer_query_names + klass.superclass::SERIALIZER_QUERY_KEYS_CACHE).uniq)
      else
        self.const_set('SERIALIZER_QUERY_KEYS_CACHE', serializer_query_names)
      end
      # Inject class methods, will have access to those queries on the class.
      klass.send(:extend, serializer_klass)

      # Class method to clear the cache of objects without having to instantiate them.
      def self.clear_serializer_cache id_or_ids
        if !id_or_ids.is_a?(Array)
          id_or_ids = [id_or_ids]
        end
        id_or_ids.each do |object_id|
          self::SERIALIZER_QUERY_KEYS_CACHE.each do |query_name|
            cache_key = "#{self.name}_____#{query_name}___#{object_id}"
            puts "(class) CLEARING SERIALIZER CACHE: #{cache_key}" if Rails.env.development?
            Rails.cache.delete(cache_key)
          end
        end
      end

      # no need to define it if inheriting class has defined it OR has been manually overridden.
      # CLASS METHODS
      klass.send(:define_singleton_method, :serializer) do |opts = {}|  
        query = opts[:json_query_override].present? ? self.send(opts[:json_query_override], opts) : serializer_query(opts)
        if Serializer.configuration.enable_includes && query[:include].present? && !opts[:skip_eager_loading]
          includes(generate_includes_from_json_query(query)).as_json(query)
        else
          # Have to use 'all' gets stack level too deep otherwise. Not sure why.
          all.as_json(query)
        end
      end

      klass.send(:define_singleton_method, :generate_includes_from_json_query) do |options = {}, klass = nil|  
        query_filter = {}
        klass = self if klass.nil?
        if options[:include].present? && !options[:skip_eager_loading]
          options[:include].each do |include_key, include_hash|
            next if include_hash[:skip_eager_loading] == true
            # Will 'next' if there is a scope that takes arguments, an instance-dependent scope.
            # Can't eager load when assocation has a instance condition for it's associative scope.
            # Might not be a real assocation
            next if klass.reflect_on_association(include_key).nil?
            next if klass.reflect_on_association(include_key).scope&.arity&.nonzero?
            query_filter[include_key] = {}
            next if include_hash.none?
            query_filter[include_key] = generate_includes_from_json_query(include_hash, klass.reflect_on_association(include_key).klass)
          end
        end
        # Does not include data, just eager-loads. Useful when methods need assocations, but you don't need association data.
        if options[:eager_include].present?
          options[:eager_include].each do |include_key|
            # Will 'next' if there is a scope that takes arguments, an instance-dependent scope.
            # Can't eager load when assocation has a instance condition for it's associative scope.
            # Might not be a real assocation
            next if klass.reflect_on_association(include_key).nil?
            next if klass.reflect_on_association(include_key).scope&.arity&.nonzero?
            query_filter[include_key] ||= {}
          end
        end
        return query_filter
      end

      klass.send(:define_singleton_method, :as_json_associations_alias_fix) do |options, data, opts = {}|  
        if data
          # Depth is almost purely for debugging purposes
          opts[:depth] ||= 0
          if options[:include].present?
            options[:include].each do |include_key, include_hash|
              # The includes doesn't have to have a hash attached. Skip it if it doesn't.
              next if include_hash.nil?
              data_key = include_key.to_s
              if include_hash[:as].present?
                if include_hash[:as].to_s == include_key.to_s
                  raise "Serializer: Cannot alias json query association to have the same as the original key; as: #{include_hash[:as].to_s}; original_key: #{include_key.to_s} on self: #{name}"
                end
                alias_name = include_hash[:as]
                data[alias_name.to_s] = data[include_key.to_s]
                data.delete(include_key.to_s)
                data_key = alias_name.to_s
              end
              # At this point, the data could be an array of objects, with no as_json options.
              if !data[data_key].is_a?(Array)
                data[data_key] = as_json_associations_alias_fix(include_hash, data[data_key], {depth: opts[:depth] + 1})
              else
                data[data_key].each_with_index do |value,i|
                  data[data_key][i] = as_json_associations_alias_fix(include_hash, value, {depth: opts[:depth] + 1})
                end
              end
            end
          end
        end
        return data
      end

      # no need to define it if inheriting class has defined it OR has been manually overridden.
      # INSTANCE Methods


      klass.send(:define_method, :as_json) do |options = {}|
        # We don't need to run this custom `as_json` multiple times, if defined on inherited class.
        if options[:ran_serialization]
          return super(options)
        end
        options[:ran_serialization] = true
        # Not caching records that don't have IDs.
        if !Serializer.configuration.disable_model_caching && self.id && options[:cache_key].present? && !(options.key?(:cache_for) && options[:cache_for].nil?)
          cache_key = "#{self.class.name}_____#{options[:cache_key]}___#{self.id}"
          if Rails.cache.exist?(cache_key)
            Rails.logger.info "Serializer: Cache reading #{cache_key}" if Serializer.configuration.debug
            return Rails.cache.read(cache_key)
          else
            data = super(options)
            data = self.class.as_json_associations_alias_fix(options, data)
            begin
              Rails.logger.info "Serializer: Caching #{cache_key} for #{(options[:cache_for] || Serializer.configuration.default_cache_time)} minutes." if Serializer.configuration.debug
              Rails.cache.write(cache_key, data, expires_in: (options[:cache_for] || Serializer.configuration.default_cache_time).minute)
            rescue Exception => e
              Rails.logger.error "Serializer: Internal Server Error on #{self.class}#as_json ID: #{self.id} for cache key: #{cache_key}"
              Rails.logger.error e.class
              Rails.logger.error e.message
              Rails.logger.error e.backtrace
            end
            return data
          end
        else
          if Serializer.configuration.debug && !Serializer.configuration.disable_model_caching && self.id && options[:cache_key].present? && options.key?(:cache_for) && options[:cache_for].nil?
            Rails.logger.info "Serializer: Caching #{cache_key} NOT caching due to `cache_for: nil`"
          end
          data = super(options)
          data = self.class.as_json_associations_alias_fix(options, data)
          return data
        end
      end

      if !klass.method_defined?(:serializer)
        klass.send(:define_method, :serializer) do |opts = {}|
          query = opts[:json_query_override].present? ? self.class.send(opts[:json_query_override], opts) : self.class.serializer_query(opts)
          if Serializer.configuration.enable_includes && query[:include].present? && self.class.column_names.include?('id') && self.id.present? && !opts[:skip_eager_loading] && self.respond_to?(:persisted?) && self.persisted?
            # It's an extra SQL call, but most likely worth it to pre-load associations
            self.class.includes(self.class.generate_includes_from_json_query(query)).find(self.id).as_json(query)
          else
            as_json(query)
          end
        end
      end

      # # SHOULD NOT BE OVERRIDDEN.
      klass.send(:define_method, :clear_serializer_cache) do
        if self.class.const_defined?("SERIALIZER_QUERY_KEYS_CACHE")
          self.class::SERIALIZER_QUERY_KEYS_CACHE.each do |query_name|
            cache_key = "#{self.class.name}_____#{query_name}___#{self.id}"
            Rails.logger.info "Serializer: CLEARING CACHE KEY: #{cache_key}" if Serializer.configuration.debug
            Rails.cache.delete(cache_key)
          end
          return true
        else
          # if Serializer.configuration.debug
            Rails.logger.error(
              """
                ERROR. COULD NOT CLEAR SERIALIZER CACHE FOR: Class #{self.class.name}
                Serializer: Class #{self.class.name} may not have the serializer module #{self.class.name}Serializer defined.
                Nor was it defined on an inheriting class.
              """
            )
          # end
          return nil
        end
      end

      serializer_query_names.each do |query_name|
        serializer_name = query_name[/(?<name>.+)_query/, :name]
        if serializer_name.nil?
          Rails.logger.error "Serializer: #{serializer_klass.name} method #{query_name} does not end in '(.+)_query', as is expected of serializers" if Serializer.configuration.debug
          next
        end
        if serializer_name == 'serializer'
          # No longer necessary to add here. We've added them above.
          # klass.send(:define_method, serializer_name) do |opts = {}|
          #   super({json_query_override: query_name}.merge(opts))
          # end
          # klass.send(:define_singleton_method, serializer_name) do |opts = {}|
          #   super({json_query_override: query_name}.merge(opts))
          # end
        else
          klass.send(:define_method, serializer_name) do |opts = {}|    
            serializer({json_query_override: query_name}.merge(opts))
          end
          klass.send(:define_singleton_method, serializer_name) do |opts = {}|    
            serializer({json_query_override: query_name}.merge(opts))
          end
        end
      end
    end
  end
  # END CLASS EVAL
end