/*
 * Copyright (c) 2012-2013 Remko Tronçon
 * Licensed under the GNU General Public License v3.
 * See Documentation/Licenses/GPLv3.txt for more information.
 */

#include <Swiften/IDN/LibIDNConverter.h>

extern "C" {
	#include <stringprep.h>
	#include <idna.h>
}

#include <vector>
#include <cassert>
#include <cstdlib>
#include <Swiften/Base/ByteArray.h>
#include <Swiften/Base/SafeAllocator.h>
#include <boost/shared_ptr.hpp>

using namespace Swift;

namespace {
	static const int MAX_STRINGPREP_SIZE = 1024;

	const Stringprep_profile* getLibIDNProfile(IDNConverter::StringPrepProfile profile) {
		switch(profile) {
			case IDNConverter::NamePrep: return stringprep_nameprep;
			case IDNConverter::XMPPNodePrep: return stringprep_xmpp_nodeprep;
			case IDNConverter::XMPPResourcePrep: return stringprep_xmpp_resourceprep;
			case IDNConverter::SASLPrep: return stringprep_saslprep;
		}
		assert(false);
		return 0;
	}

	template<typename StringType, typename ContainerType>
	ContainerType getStringPreparedInternal(const StringType& s, IDNConverter::StringPrepProfile profile) {
		ContainerType input(s.begin(), s.end());
		input.resize(MAX_STRINGPREP_SIZE);
		if (stringprep(&input[0], MAX_STRINGPREP_SIZE, static_cast<Stringprep_profile_flags>(0), getLibIDNProfile(profile)) == 0) {
			return input;
		}
		else {
			return ContainerType();
		}
	}
}

namespace Swift {

std::string LibIDNConverter::getStringPrepared(const std::string& s, StringPrepProfile profile) {
	std::vector<char> preparedData = getStringPreparedInternal< std::string, std::vector<char> >(s, profile);
	if (preparedData.empty()) {
		throw std::exception();
	}
	return std::string(vecptr(preparedData));
}

SafeByteArray LibIDNConverter::getStringPrepared(const SafeByteArray& s, StringPrepProfile profile) {
	std::vector<char, SafeAllocator<char> > preparedData = getStringPreparedInternal<SafeByteArray, std::vector<char, SafeAllocator<char> > >(s, profile);
	if (preparedData.empty()) {
		throw std::exception();
	}
	return createSafeByteArray(reinterpret_cast<const char*>(vecptr(preparedData)));
}

std::string LibIDNConverter::getIDNAEncoded(const std::string& domain) {
	char* output;
	if (idna_to_ascii_8z(domain.c_str(), &output, 0) == IDNA_SUCCESS) {
		std::string result(output);
		free(output);
		return result;
	}
	else {
		return domain;
	}
}

}