module Ransack::Helpers::FormHelper

def extract_search_and_routing_proxy(search)
  return [search[1], search[0]] if search.is_a?(Array)
  [search, nil]
end

def html_option_for(option, search)
  return option.to_s if option.present?
  "#{search.klass.to_s.underscore}_search"
end

def options_for(record)
  record.map { |r| parse_record(r) }
end

def parse_record(object)
  return object.klass if object.is_a?(Ransack::Search)
  object
end

def search_form_for(record, options = {}, &proc)
  if record.is_a? Ransack::Search
    search = record
    options[:url] ||= polymorphic_path(
      search.klass, format: options.delete(:format)
      )
  elsif record.is_a?(Array) &&
  (search = record.detect { |o| o.is_a?(Ransack::Search) })
    options[:url] ||= polymorphic_path(
      options_for(record), format: options.delete(:format)
      )
  else
    raise ArgumentError,
    'No Ransack::Search object was provided to search_form_for!'
  end
  options[:html] ||= {}
  html_options = {
    class:  html_option_for(options[:class], search),
    id:     html_option_for(options[:id], search),
    method: :get
  }
  options[:as] ||= Ransack.options[:search_key]
  options[:html].reverse_merge!(html_options)
  options[:builder] ||= FormBuilder
  form_for(record, options, &proc)
end

def sort_link(search_object, attribute, *args, &block)
  search, routing_proxy = extract_search_and_routing_proxy(search_object)
  unless Search === search
    raise TypeError, 'First argument must be a Ransack::Search!'
  end
  args[args.first.is_a?(Array) ? 1 : 0, 0] = capture(&block) if block_given?
  s = SortLink.new(search, attribute, args, params, &block)
  link_to(s.name, url(routing_proxy, s.url_options), s.html_options(args))
end

def sort_url(search_object, attribute, *args)
  search, routing_proxy = extract_search_and_routing_proxy(search_object)
  unless Search === search
    raise TypeError, 'First argument must be a Ransack::Search!'
  end
  s = SortLink.new(search, attribute, args, params)
  url(routing_proxy, s.url_options)
end

def url(routing_proxy, options_for_url)
  if routing_proxy && respond_to?(routing_proxy)
    send(routing_proxy).url_for(options_for_url)
  else
    url_for(options_for_url)
  end
end