module Crystal  
  class ModelHelper
    attr_accessor :template, :model_name, :model, :options, :form_helper
    
    def initialize template, form_helper, model_name, model, options
      self.template, self.form_helper, self.model_name, self.model, self.options = template, form_helper, model_name, model, options
    end

      
    # 
    # Helpers
    # 
    def check_box name, options = {}      
      render_attribute name, options do |fname, value, o|
        form_helper.check_box_tag fname, !!value, o
      end
    end
        
    def file_field name, options = {}
      render_attribute name, options do |fname, value, o|
        form_helper.file_field_tag fname, o
      end
    end
    
    def hidden_field name, options = {}
      render_attribute name, options do |fname, value, o|
        form_helper.hidden_field_tag fname, value, o
      end
    end
    
    def password_field name, options = {}
      render_attribute name, options do |fname, value, o|
        form_helper.password_field_tag fname, nil, o
      end
    end
    
    def radio_button name, options = {}
      render_attribute name, options do |fname, value, o|
        form_helper.radio_button_tag fname, !!value, o
      end
    end
    
    def submit value, options = {}
      form_helper.submit_tag value, options
    end
    
    def text_field name, options = {}
      render_attribute name, options do |fname, value, o|
        form_helper.text_field_tag fname, value, o
      end
    end
    
    def text_area name, options = {}
      render_attribute name, options do |fname, value, o|
        form_helper.text_area_tag fname, value, o
      end
    end
    
    def error_messages
      merrors = errors['base']      
      form_helper.error_messages merrors.to_a unless merrors.blank?
    end
    
    
    protected
      def method_missing m, *args, &b
        form_helper.send m, *args, &b
      end
    
      def render_attribute name, options, &block
        name = name.to_s
        ferrors = errors_for(name)
        
        if form_helper.respond_to? :field_with_errors
          field_html = block.call field_name_for(name), value_of(name), options
          unless ferrors.blank?
            form_helper.field_with_errors name, ferrors, options, field_html
          else
            field_html
          end
        else
          options['errors'] = ferrors          
          block.call field_name_for(name), value_of(name), options
        end
      end
    
      def errors
        unless @errors
          @errors = {}
          (
            (model.respond_to?(:errors) && model.errors) || 
            (model.respond_to?(:[]) && (model['errors'] || model[:errors])) || 
            {}
          ).each do |k, v|
            @errors[k.to_s] = v
          end          
        end
        @errors
      end
    
      def errors_for name
        errors[name].to_a
      end
    
      def field_name_for name
        "#{model_name}[#{name}]"
      end
    
      def value_of name      
        if model.respond_to? name 
          model.send name
        elsif model.respond_to? :[]
          model[name.to_s] || model[name.to_sym]
        else
          raise "Model not respond to :#{name} nor to :[]!"
        end
      end
  end
end