#include "telnet_connection.h"
#include "commands.h"

#include <boost/bind.hpp>
#include <boost/algorithm/string.hpp>
#include <boost/spirit/include/qi.hpp>

#include <iostream>

namespace qi = boost::spirit::qi;

telnet::Connection::Connection(boost::asio::io_service& io_service) : socket(io_service) {
}

void telnet::Connection::handle_read(const boost::system::error_code& error, size_t bytes_transferred) {
	if(error) {
		return;
	}

	std::string line;
	std::istream is(&buf);
	std::getline(is, line);
	boost::trim(line);

	if(line == "exit") {
		return;
	}

	std::vector<std::string> args;

	// failed to parse or no arguments, i.e. empty line
	if(!parse_args(line, args) || !args.size()) {
		start();
		return;
	}

	std::vector<std::string> r;
	try {
		Commands cmd(socket.get_io_service(), args);
		r = cmd();
	} catch(CommandException& ce) {
		std::string s(ce.what());
		s += '\n';
		boost::asio::write(socket, boost::asio::buffer(s));
		start();
		return;
	}

	for(std::vector<std::string>::iterator it = r.begin(); it != r.end(); it++) {
		boost::asio::write(socket, boost::asio::buffer(*it + "\n"));
	}

	start();
}

/** Parse a given line and return a vector with its arguments.
 *  Arguments which are surrounded by "quotes" are interpreted as a single argument.
 */
bool telnet::Connection::parse_args(std::string& line, std::vector<std::string>& args) {
	std::string::const_iterator begin = line.begin(), end = line.end();

	return qi::parse(begin, end,
		// find "words in quotes"
		(('"' >> *(qi::char_ - '"') >> '"') |
		// single words
		*(qi::char_ - ' ')) %
		// skip spaces between arguments
		+qi::char_(' '), args);
}

void telnet::Connection::start() {
	boost::asio::async_read_until(socket, buf, "\n", boost::bind(&Connection::handle_read, shared_from_this(),
				boost::asio::placeholders::error, boost::asio::placeholders::bytes_transferred));
}