#ifndef _command__hpp__included__
#define _command__hpp__included__

#include <stdexcept>
#include <string>


class window;

/**
 * A command.
 */
class command
{
public:
/**
 * Register a new command.
 *
 * parameter cmd: The command to register.
 * throws std::bad_alloc: Not enough memory.
 */
	command(const std::string& cmd) throw(std::bad_alloc);

/**
 * Deregister a command.
 */
	virtual ~command() throw();

/**
 * Invoke a command.
 *
 * parameter arguments: Arguments to command.
 * parameter window: Handle to graphics system.
 * throws std::bad_alloc: Not enough memory.
 * throws std::runtime_error: Command execution failed.
 */
	virtual void invoke(const std::string& arguments, window* win) throw(std::bad_alloc, std::runtime_error) = 0;

/**
 * Look up and invoke a command. The command will undergo alias expansion and recursion checking.
 *
 * parameter cmd: Command to exeucte.
 * parameter window: Handle to graphics system.
 */
	static void invokeC(const std::string& cmd, window* win) throw();

/**
 * Get short help for command.
 */
	virtual std::string get_short_help() throw(std::bad_alloc);

/**
 * Get long help for command.
 */
	virtual std::string get_long_help() throw(std::bad_alloc);
private:
	command(const command&);
	command& operator=(const command&);
	std::string commandname;
};

/**
 * Splits string to fields on ' ' and '\t', with multiple whitespace collapsed into one.
 */
class tokensplitter
{
public:
/**
 * Create a new splitter.
 *
 * parameter _line: The line to start splitting.
 * throws std::bad_alloc: Not enough memory.
 */
	tokensplitter(const std::string& _line) throw(std::bad_alloc);
/**
 * Is there more coming?
 *
 * returns: True if there is more, false otherwise.
 * throws std::bad_alloc: Not enough memory.
 */
	operator bool() throw();
/**
 * Get the next token.
 *
 * returns: The next token from line. If there is no more tokens, returns "".
 * throws std::bad_alloc: Not enough memory.
 */
	operator std::string() throw(std::bad_alloc);
/**
 * Get all that is remaining.
 *
 * returns: All remaining parts of line as-is.
 * throws std::bad_alloc: Not enough memory.
 */
	std::string tail() throw(std::bad_alloc);
private:
	std::string line;
	size_t position;
};


#endif