/*************************************************************************
** XMLDocument.cpp                                                      **
**                                                                      **
** This file is part of dvisvgm -- the DVI to SVG converter             **
** Copyright (C) 2005-2013 Martin Gieseking <martin.gieseking@uos.de>   **
**                                                                      **
** This program 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 3 of       **
** the License, or (at your option) any later version.                  **
**                                                                      **
** This program 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 this program; if not, see <http://www.gnu.org/licenses/>. **
*************************************************************************/

#include "macros.h"
#include "XMLDocument.h"

using namespace std;

XMLDocument::XMLDocument (XMLElementNode *root)
	: _rootElement(root), _emitted(false)
{
}


XMLDocument::~XMLDocument () {
	clear();
}


void XMLDocument::clear () {
	delete _rootElement;
	_rootElement = 0;
	FORALL(_nodes, list<XMLNode*>::iterator, i)
		delete *i;
	_nodes.clear();
}


void XMLDocument::append (XMLNode *node) {
	if (!node)
		return;
	XMLElementNode *newRoot = dynamic_cast<XMLElementNode*>(node);
	if (newRoot) {             // there can only be one root element node in the document
		delete _rootElement;     // so if there is already one...
		_rootElement = newRoot;  // ...we replace it
	}
	else
		_nodes.push_back(node);
}


void XMLDocument::setRootNode (XMLElementNode *root) {
	delete _rootElement;
	_rootElement = root;
}


ostream& XMLDocument::write (ostream &os) const {
	if (_rootElement) { // no root element => no output
		os << "<?xml version='1.0'?>\n";
		FORALL(_nodes, list<XMLNode*>::const_iterator, i)
			(*i)->write(os);
		_rootElement->write(os);
	}
	return os;
}

/** Writes a part of the XML document to the given output stream and removes
 *  the completely written nodes. The output stops when a stop node is reached
 *  (this node won't be printed at all). If a node was only partly emitted, i.e.
 *  its child was the stop node, a further call of emit will continue the output.
 *  @param[in] os stream to which the output is written
 *  @param[in] stopElement node where emitting stops (if 0 the whole tree will be emitted)
 *  @return true if node was completely emitted */
bool XMLDocument::emit (ostream& os, XMLNode *stopNode) {
	if (_rootElement) {  // no root element => no output
		if (!_emitted) {
			os << "<?xml version='1.0' encoding='ISO-8859-1'?>\n";
			_emitted = true;
		}
		FORALL(_nodes, list<XMLNode*>::iterator, i) {
			if ((*i)->emit(os, stopNode)) {
				list<XMLNode*>::iterator it = i++;  // prevent i from being invalidated...
				_nodes.erase(it);              // ... by erase
				--i;  // @@ what happens if i points to first child?
			}
			else
				return false;
		}
		return _rootElement->emit(os, stopNode);
	}
	return true;
}