module LaserLemon
  module SearchParty
    module Request
      def self.included(base)
        base.cattr_accessor :search_parameter_models
        base.search_parameter_models = {}
        
        base.cattr_accessor :search_parameter_finders
        base.search_parameter_finders = {}
        base.search_parameter_finders.default = :find_by_id
        
        base.cattr_accessor :search_parameter_patterns
        base.search_parameter_patterns = []
      end
      
      def search_parameters
        @search_parameters ||= parse_hash(query_parameters)
      end
      
      private
      
      def parse_hash(hash)
        hash.symbolize_keys.inject({}) do |new_hash, (key, value)|
          parsed_value = case value
          when Hash then parse_hash(value)
          when Array then value.map{|v| parse_value(v) }
          else parse_value(v)
          end
          new_value = if model_name = self.class.search_parameter_models[key]
            model = model_name.to_s.classify.constantize
            finder = self.class.search_parameter_finders[key]
            new_values = [*parsed_value].map{|v| model.send(finder, v) }
            parsed_value.is_a?(Array) ? new_values.dup : new_values.first
          else
            parsed_value
          end
          new_hash.update(key => new_value)
        end.with_indifferent_access
      end
      
      def parse_value(value)
        if p = self.class.search_parameter_patterns.detect{|r,v| r.match(value) }
          (v = p.last).respond_to?(:call) ? v.call($~) : v
        else
          value
        end
      end
    end
    
    module Controller
      def self.included(base)
        base.attr_internal :search_params
        
        base.class_eval do
          alias_method_chain :assign_shortcuts, :search_party
        end
      end
      
      def assign_shortcuts_with_search_party(request, response)
        @_search_params = request.search_parameters
        assign_shortcuts_without_search_party(request, response)
      end
    end
    
    module View
      def self.included(base)
        base.delegate :search_params, :to => :controller
      end
    end
  end
end

ActionController::Request.send(:include, LaserLemon::SearchParty::Request)
ActionController::Base.send(:include, LaserLemon::SearchParty::Controller)
ActionView::Base.send(:include, LaserLemon::SearchParty::View)