require 'volt/page/targets/base_section'

class DomSection < BaseSection
  def initialize(binding_name)
    @start_node = find_by_comment("$#{binding_name}")
    @end_node = find_by_comment("$/#{binding_name}")
  end
  
	def find_by_comment(text, in_node=`document`)
		node = nil

		%x{
			node = document.evaluate("//comment()[. = ' " + text + " ']", in_node, null, XPathResult.UNORDERED_NODE_ITERATOR_TYPE, null).iterateNext();
		}
		return node
	end

  def text=(value)
    %x{
      this.$range().deleteContents();
      this.$range().insertNode(document.createTextNode(#{value}));
    }
  end

  def remove
    range = self.range()

    %x{
      range.deleteContents();
    }
  end
  
  def remove_anchors    
    %x{
      this.start_node.parentNode.removeChild(this.start_node);
      this.end_node.parentNode.removeChild(this.end_node);
    }
    @start_node = nil
    @end_node = nil
  end
  
  def insert_anchor_before_end(binding_name)
    Element.find(@end_node).before("<!-- $#{binding_name} --><!-- $/#{binding_name} -->")
  end
  
  # Takes in an array of dom nodes and replaces the current content
  # with the new nodes
  def nodes=(nodes)
    range = self.range()

    %x{
      range.deleteContents();

      for (var i=nodes.length-1; i >= 0; i--) {
        var node = nodes[i];

        node.parentNode.removeChild(node);
        range.insertNode(node);
      }
    }
  end
  
	# Takes in our html and bindings, and rezero's the comment names, and the
	# bindings.  Returns an updated bindings hash
	def set_content_and_rezero_bindings(html, bindings)
		sub_nodes = nil
    temp_div = nil

    %x{
      temp_div = document.createElement('div');
      var doc = jQuery.parseHTML(html);
  
      for (var i=0;i < doc.length;i++) {
        temp_div.appendChild(doc[i]);
      }
    }

    new_bindings = {}
    # Loop through the bindings, and rezero.
    bindings.each_pair do |name,binding|
      new_name = @@binding_number

      if name.cur.is_a?(String)
        if name[0..1] == 'id'
        # Find by id
          %x{
            var node = temp_div.querySelector('#' + name);
            node.setAttribute('id', 'id' +new_name);
          }
          
          new_bindings["id#{new_name}"] = binding
        else
          # Assume a fixed id
          # TODO: We should raise an exception if this id is already on the page
          new_bindings[name] = binding
        end
      else
        # Change the comment ids
        start_comment = find_by_comment("$#{name}", temp_div)
        end_comment = find_by_comment("$/#{name}", temp_div)

        %x{
          start_comment.textContent = " $" + new_name + " ";
          end_comment.textContent = " $/" + new_name + " ";
        }

        new_bindings[new_name] = binding
      end


      @@binding_number += 1
    end


    children = nil
		%x{
		  children = temp_div.childNodes;
		}
    
    # Update the nodes
    self.nodes = children
    
    %x{
      temp_div = null;
    }

		return new_bindings
	end
  
  private
  
    def range
      return @range if @range

  		range = nil
  		%x{
  		  range = document.createRange();
  		  range.setStartAfter(this.start_node);
  		  range.setEndBefore(this.end_node);
  		}

      @range = range

  		return range
    end

end