/*
 * Copyright (c) 2010 Remko Tronçon
 * Licensed under the GNU General Public License v3.
 * See Documentation/Licenses/GPLv3.txt for more information.
 */

#include <Swiften/StringCodecs/Hexify.h>

#include <sstream>
#include <iomanip>
#include <boost/numeric/conversion/cast.hpp>

#include <string>
#include <Swiften/Base/ByteArray.h>

#pragma clang diagnostic ignored "-Wconversion"

namespace Swift {

std::string Hexify::hexify(unsigned char byte) {
	std::ostringstream result;
	result << std::hex << std::setw(2) << std::setfill('0') << boost::numeric_cast<unsigned int>(byte);
	return std::string(result.str());
}

std::string Hexify::hexify(const ByteArray& data) {
	std::ostringstream result;
	result << std::hex;

	for (unsigned int i = 0; i < data.size(); ++i) {
		result << std::setw(2) << std::setfill('0') << boost::numeric_cast<unsigned int>(static_cast<unsigned char>(data[i]));
	}
	return std::string(result.str());
}


static const unsigned char map[256] = {
	255, 255, 255, 255, 255, 255, 255, 255,
	255, 255, 255, 255, 255, 255, 255, 255,
	255, 255, 255, 255, 255, 255, 255, 255, 
	255, 255, 255, 255, 255, 255, 255, 255,
	255, 255, 255, 255, 255, 255, 255, 255,
	255, 255, 255, 255, 255, 255, 255, 255,
	0,   1,   2,   3,   4,   5,   6,   7,
	8,   9,   255, 255, 255, 255, 255, 255,
	255, 10,  11,  12,  13,  14,  15,  255,
	255, 255, 255, 255, 255, 255, 255, 255,
	255, 255, 255, 255, 255, 255, 255, 255,
	255, 255, 255, 255, 255, 255, 255, 255,
	255, 10,  11,  12,  13,  14,  15,  255,
	255, 255, 255, 255, 255, 255, 255, 255,
	255, 255, 255, 255, 255, 255, 255, 255,
	255, 255, 255, 255, 255, 255, 255, 255
};

ByteArray Hexify::unhexify(const std::string& in) {
	if (in.size() % 2) {
		return ByteArray();
	}

	ByteArray result(in.size() / 2);
	for (size_t pos = 0; pos < in.size() - 1; pos += 2) {
		unsigned char a = map[static_cast<size_t>(in[pos])];
		unsigned char b = map[static_cast<size_t>(in[pos+1])];
		if (a == 255 || b == 255) {
			return ByteArray();
		}
		result[pos/2] = (a<<4) | b;
	}
	return result;
}

}