Jupiter-Bot/Bot/Generic_Command.h

/**
 * Copyright (C) 2015 Justin James.
 *
 * This license must be preserved.
 * Any applications, libraries, or code which make any use of any
 * component of this program must not be commercial, unless explicit
 * permission is granted from the original author. The use of this
 * program for non-profit purposes is permitted.
 *
 * 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.
 *
 * In the event that this license restricts you from making desired use of this program, contact the original author.
 * Written by Justin James <justin.aj@hotmail.com>
 */

#if !defined _GENERIC_COMMAND_H_HEADER
#define _GENERIC_COMMAND_H_HEADER

/**
* @file Generic_Command.h
* @brief Provides an extendable command system.
*/

#include "Jupiter/Command.h"
#include "Jupiter/String.h"
#include "Jupiter_Bot.h"

class GenericCommand;

/** DLL Linkage Nagging */
#if defined _MSC_VER
#pragma warning(push)
#pragma warning(disable: 4251)
#endif

/** Generic command list */
JUPITER_BOT_API extern Jupiter::ArrayList<GenericCommand> *genericCommands;

/**
* @brief Provides the base for generic commands.
*/
class JUPITER_BOT_API GenericCommand : public Jupiter::Command
{
public:
	/** Enumerated class to guide output in generic command interpreters */
	enum class DisplayType
	{
		PublicSuccess,
		PrivateSuccess,
		PublicError,
		PrivateError,
	};

	/** Data entry returned by trigger() */
	struct JUPITER_BOT_API ResponseLine
	{
		Jupiter::StringS response;
		GenericCommand::DisplayType type;
		ResponseLine *next = nullptr;

		/**
		* @brief Sets the response and type of the ResponseLine.
		*
		* @param in_response Value to set response to.
		* @param in_type Value to set type to.
		* @return This.
		*/
		ResponseLine *set(const Jupiter::ReadableString &response, GenericCommand::DisplayType type);
		ResponseLine() = default;
		ResponseLine(const Jupiter::ReadableString &response, GenericCommand::DisplayType type);
	};

	/**
	* @brief Called when the command is to be executed.
	*
	* @param input Parameters passed to the command by the user.
	*/
	virtual ResponseLine *trigger(const Jupiter::ReadableString &input) = 0;

	/**
	* @brief Default constructor for the generic command class.
	*/
	GenericCommand();

	/**
	* @brief Destructor for the generic command class.
	*/
	~GenericCommand();
};

/**
* @brief Fetches a generic command based on its trigger.
*
* @param trigger Trigger of the command to fetch.
* @return A generic command if it exists, nullptr otherwise.
*/
JUPITER_BOT_API extern GenericCommand *getGenericCommand(const Jupiter::ReadableString &trigger);

/** Generic Command Macros */

/** Defines the core of a generic command's declaration. This should be included in every generic command. */
#define BASE_GENERIC_COMMAND(CLASS) \
	public: \
	CLASS(); \
	GenericCommand::ResponseLine *trigger(const Jupiter::ReadableString &parameters); \
	const Jupiter::ReadableString &getHelp(const Jupiter::ReadableString &parameters); \
	static CLASS instance;

/** Expands to become the entire declaration for a generic command. In most cases, this will be sufficient. */
#define GENERIC_GENERIC_COMMAND(CLASS) \
class CLASS : public GenericCommand { \
	BASE_GENERIC_COMMAND(CLASS) \
};

/** Instantiates a generic command. */
#define GENERIC_COMMAND_INIT(CLASS) \
	CLASS CLASS :: instance = CLASS (); \
	CLASS & CLASS ## _instance = CLASS :: instance;

/** Re-enable warnings */
#if defined _MSC_VER
#pragma warning(pop)
#endif

#endif // _GENERIC_COMMAND_H_HEADER