/**
 *  @file
 *  @author     2012-2013 Stefan Radomski (stefan.radomski@cs.tu-darmstadt.de)
 *  @copyright  Simplified BSD
 *
 *  @cond
 *  This program is free software: you can redistribute it and/or modify
 *  it under the terms of the FreeBSD license as published by the FreeBSD
 *  project.
 *
 *  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.
 *
 *  You should have received a copy of the FreeBSD license along with this
 *  program. If not, see <http://www.opensource.org/licenses/bsd-license>.
 *  @endcond
 */

#include <uscxml/Common.h>
#include "uscxml/UUID.h"
#include "uscxml/DOMUtils.h"
#include <uscxml/Convenience.h>
#include <glog/logging.h>
#include <SAX/helpers/InputSourceResolver.hpp>

namespace uscxml {


bool DOMUtils::attributeIsTrue(const::std::string& value) {
	return (iequals(value, "on") ||
	        iequals(value, "true") ||
	        iequals(value, "1") ||
	        iequals(value, "yes"));
}

std::string DOMUtils::xPathForNode(const Arabica::DOM::Node<std::string>& node, const std::string& ns) {
	std::string xPath;
	std::string nsPrefix;

	if (ns.size() > 0) {
		nsPrefix = ns + ":";
	}

	if (!node || node.getNodeType() != Arabica::DOM::Node_base::ELEMENT_NODE)
		return xPath;

	Arabica::DOM::Node<std::string> curr = node;
	while(curr) {
		switch (curr.getNodeType()) {
		case Arabica::DOM::Node_base::ELEMENT_NODE: {
			Arabica::DOM::Element<std::string> elem = Arabica::DOM::Element<std::string>(curr);
			if (HAS_ATTR(elem, "id") && !UUID::isUUID(ATTR(elem, "id"))) {
				// we assume ids to be unique and return immediately
				if (ns == "*") {
					xPath.insert(0, "//*[local-name() = \"" + TAGNAME(elem) + "\"][@id=\"" + ATTR(elem, "id") + "\"]");
				} else {
					xPath.insert(0, "//" + nsPrefix + TAGNAME(elem) + "[@id=\"" + ATTR(elem, "id") + "\"]");
				}
				return xPath;
			} else {
				// check previous siblings to count our index
				Arabica::DOM::Node<std::string> sibling = curr.getPreviousSibling();
				int index = 1; // xpath indices start at 1
				while(sibling) {
					if (sibling.getNodeType() == Arabica::DOM::Node_base::ELEMENT_NODE) {
						if (iequals(TAGNAME_CAST(sibling), TAGNAME(elem))) {
							index++;
						}
					}
					sibling = sibling.getPreviousSibling();
				}
				if (ns == "*") {
					xPath.insert(0, "/*[local-name() = \"" + TAGNAME(elem) + "\"][" + toStr(index) + "]");
				} else {
					xPath.insert(0, "/" + nsPrefix + TAGNAME(elem) + "[" + toStr(index) + "]");
				}
			}
			break;
		}
		case Arabica::DOM::Node_base::DOCUMENT_NODE:
			return xPath;
		default:
			LOG(ERROR) << "Only nodes of type element supported for now";
			return "";
			break;
		}
		curr = curr.getParentNode();
	}
	return xPath;
}

std::list<Arabica::DOM::Node<std::string> > DOMUtils::getElementsByType(const Arabica::DOM::Node<std::string>& root, Arabica::DOM::Node_base::Type type) {
	std::list<Arabica::DOM::Node<std::string> > result;
	std::list<Arabica::DOM::Node<std::string> > stack;
	std::list<Arabica::DOM::Node<std::string> >::iterator stackIter;

	if (!root)
		return result;

	stack.push_back(root);
	while(stack.size() > 0) {
//		for(stackIter = stack.begin(); stackIter != stack.end(); stackIter++) {
//			std::cout << stackIter->getNodeType() << " " << stackIter->getLocalName() << " " << stackIter->getNodeValue() << std::endl;
//		}
//		std::cout << std::endl;

		Arabica::DOM::Node<std::string> currNode = stack.back();
		if (currNode.hasChildNodes()) {
			stack.push_back(currNode.getFirstChild());
			continue;
		}

		// roll back stack and pop everyone without next sibling
		do {
			currNode = stack.back();
			if (currNode.getNodeType() == type)
				result.push_back(currNode);
			stack.pop_back();
			if (currNode.getNextSibling()) {
				stack.push_back(currNode.getNextSibling());
				break;
			}
		} while(stack.size() > 0);
	}
	return result;
}

NameSpacingParser NameSpacingParser::fromXML(const std::string& xml) {
	std::stringstream* ss = new std::stringstream();
	(*ss) << xml;
	// we need an auto_ptr for arabica to assume ownership
	std::auto_ptr<std::istream> ssPtr(ss);
	Arabica::SAX::InputSource<std::string> inputSource;
	inputSource.setByteStream(ssPtr);
	return fromInputSource(inputSource);
}

NameSpacingParser NameSpacingParser::fromInputSource(Arabica::SAX::InputSource<std::string>& source) {
	NameSpacingParser parser;
	if(!parser.parse(source) || !parser.getDocument().hasChildNodes()) {
		if(parser._errorHandler.errorsReported()) {
//			LOG(ERROR) << "could not parse input:";
//			LOG(ERROR) << parser._errorHandler.errors() << std::endl;
		} else {
			Arabica::SAX::InputSourceResolver resolver(source, Arabica::default_string_adaptor<std::string>());
			if (!resolver.resolve()) {
				LOG(ERROR) << source.getSystemId() << ": no such file";
			}
		}
	}
	return parser;
}

NameSpacingParser::NameSpacingParser() {
	setErrorHandler(_errorHandler);
}

void NameSpacingParser::startPrefixMapping(const std::string& prefix, const std::string& uri) {
	nameSpace.insert(std::make_pair(uri, prefix));
}

}