/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/***************************************************************************
 *            macro.cc
 *
 *  Fri Aug 31 13:40:17 CEST 2007
 *  Copyright 2007 Bent Bisballe Nyeng and Lars Bisballe Jensen
 *  deva@aasimon.org and elsenator@gmail.com
 ****************************************************************************/

/*
 *  This file is part of Pracro.
 *
 *  Pracro is free software; you can redistribute it and/or modify
 *  it under the terms of the GNU General Public License as published by
 *  the Free Software Foundation; either version 2 of the License, or
 *  (at your option) any later version.
 *
 *  Pracro is distributed in the hope that it will be useful,
 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *  GNU General Public License for more details.
 *
 *  You should have received a copy of the GNU General Public License
 *  along with Pracro; if not, write to the Free Software
 *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA.
 */
#include "macro.h"
#include "sendrecieve.h"
#include <QDomDocument>
#include <QApplication>

#define MACRO_EVENT_ID 65432

QLinkedList< MacroWindow * > macrowindows;

extern QString cpr;
extern QString user;
extern QString host;
extern quint16 port;

/**
 * Macro Event used to trigger the creation of a new macro
 */
class MacroEvent : public QEvent {
public:
  MacroEvent(QString course, QString macro) :
    QEvent((QEvent::Type)MACRO_EVENT_ID),
    macro(macro),
    course(course) {}
  QString macro;
  QString course;
};

/**
 * Macro Event Filter used to catch the Macro Events.
 */
class MacroEventFilter : public QObject {
protected:
  bool eventFilter( QObject *o, QEvent *e );
};

/**
 * The single global macro event filter.
 * It is created the first time new_macro is called.
 */
MacroEventFilter *macro_event_filter = NULL;

/**
 * This function sends a request to the praco server, and returns the
 * parsed answer.
 */
static QDomDocument xml_request(QString course, QString macro)
{
  // Create the xml request array
  QByteArray xml_array;
  printf("course: %s, macro: %s, cpr: %s, user: %s\n",
         course.toStdString().c_str(),
         macro.toStdString().c_str(),
         cpr.toStdString().c_str(),
         user.toStdString().c_str());
  xml_array.append("<?xml version=\"1.0\" encoding=\"UTF-8\"?>\n");
  xml_array.append("<pracro version=\"1.0\" cpr=\"" + cpr + "\" user=\"" + user + "\">\n");
  xml_array.append("  <request course=\"" + course + "\" macro=\"" + macro + "\"/>\n");
  xml_array.append("</pracro>");

  // Print to stdout for debug purposes
  char *test = xml_array.data();
  printf("%s\n", test);

  // Parse the XML document using setContent of QDomDocument
  QDomDocument xml_req;
  if (!xml_req.setContent(xml_array)) {
    printf("Error: Invalid XML found in request\n");
  }

  return xml_req;
}

/**
 * Create the new macro
 */
static void create_macro(QString course, QString macro)
{
  // Build the XML request
  QDomDocument xml_req = xml_request(course, macro);

  // Fetch the XML document
  SendRecieve xml_acquire(host, port);
  xml_acquire.makeConnection(&xml_req);
  QByteArray ba = xml_acquire.getResult();

  // Print to stdout, for debug purposes
  char *test = ba.data();
  printf("%s\n", test);

  // Parse the XML document using setContent of QDomDocument
  QDomDocument xml_doc;
  if (!xml_doc.setContent(ba)) {
    printf("ERROR: Invalid XML recieved!\n");
    fwrite(ba.data(), ba.size(), 1, stdout);
    return;
  }

  cleanup_macros();

  //
  // TODO: This is where the dependency checking should occur.
  //

  // Initiate the new macro window with the xml document and push
  //  it to the window list
  QDomNodeList courses = xml_doc.documentElement().childNodes();
  QDomNode coursenode = courses.at(0); // There can be only one!
  QDomNodeList macros = coursenode.childNodes();
  for(int j = 0; j < macros.count(); j++) {
    QDomNode macronode = macros.at(j);
    // Only create if the macro contains something.
    if(macronode.childNodes().count())
      macrowindows.push_back( new MacroWindow( macronode ) );
  }
}

bool MacroEventFilter::eventFilter( QObject *, QEvent *e )
{
  if ( e->type() == MACRO_EVENT_ID ) {
    MacroEvent *event = (MacroEvent*)e;
    create_macro(event->course, event->macro);
    return TRUE; // eat event
  } else {
    return FALSE;
  }
}

// Delete all closed windows from window list
void cleanup_macros()
{
  int dead = 0;
  int live = 0;

  QLinkedList< MacroWindow * >::iterator i = macrowindows.begin();
  while(i != macrowindows.end()) {
    if( (*i)->isClosed() ) {
      dead++;
      delete *i;
      i = macrowindows.erase(i);
    } else {
      live++;
      i++;
    }
  }
  printf("Found %d live ones and %d dead ones.\n", live, dead);
}

void new_macro(QString course, QString macro)
{
  if(macro_event_filter == NULL) {
    macro_event_filter = new MacroEventFilter();
    qApp->installEventFilter( macro_event_filter );
  }

  MacroEvent *event = new MacroEvent(course, macro);
  qApp->postEvent(qApp, event);
  qApp->processEvents(); // To prevent QT from closing when no windows are present
}