/////////////////////////////////////////////////////////////////////
// DemoXml.cpp - Demo how to use XmlDocument to perist Widgets     //
//                                                                 //
// Jim Fawcett, CSE687 - Object Oriented Design, Spring 2017       //
/////////////////////////////////////////////////////////////////////

#include "DemoXml.h"
#include "../Convert/Convert.h"
#include "../XmlDocument/XmlDocument/XmlDocument.h"
#include "../XmlDocument/XmlElement/XmlElement.h"
#include "StrHelper.h"

using namespace XmlProcessing;
using SPtr = std::shared_ptr<AbstractXmlElement>;

//----< persist Widget object to XML string >------------------------

std::string widgetToXml(const Widget& widget)
{
  XmlDocument doc;
  
  SPtr pRoot = makeTaggedElement("widget");
  doc.docElement() = pRoot;

  // make Property<string> name element and add to root
  SPtr pNameElem = makeTaggedElement("name");
  pRoot->addChild(pNameElem);
  SPtr pTextNode = makeTextElement(widget.name);
  pNameElem->addChild(pTextNode);
  
  // make Property<double> pi element and add to root
  SPtr pPiElem = makeTaggedElement("pi");
  pRoot->addChild(pPiElem);
  std::string body = Convert<double>::toString(widget.pi);
  pTextNode = makeTextElement(body);
  pPiElem->addChild(pTextNode);

  return doc.toString();
}

//----< deserialize Widget object from XML string >------------------
/*
 * - XML returned from doc.toString() is indented.
 *   We need to trim text node values to remove indenting chars,
 *   e.g., newlines and spaces.
 * - That functionality is provided in StrHelper.h
 *
 */
Widget widgetFromXml(const std::string& xml)
{
  Widget widget;
  
  XmlDocument doc(xml, XmlDocument::str);

  std::vector<SPtr> desc = doc.descendents("name").select();
  std::string name_value = desc[0]->children()[0]->value();
  widget.name = trim(name_value);
  desc = doc.descendents("pi").select();
  std::string pi_value = desc[0]->children()[0]->value();
  pi_value = trim(pi_value);
  widget.pi = Convert<double>::fromString(pi_value);

  return widget;
}

int main()
{
  Widget widget;
  widget.name = "jim";

  std::string xml = widgetToXml(widget);
  std::cout << "\n  Widget Xml:" << xml;
  std::cout << "\n";

  std::cout << "\n  new Widget instantiated from XML";
  Widget newWidget = widgetFromXml(xml);
  std::cout << "\n  widget.name = " << newWidget.name;
  std::cout << "\n  widget.pi =   " << newWidget.pi;

  std::cout << "\n\n";
}