#ifndef _INCLUDE_SOURCEMOD_MODULE_INTERFACE_H_

#define _INCLUDE_SOURCEMOD_MODULE_INTERFACE_H_

#include <IShareSys.h>

#include <ILibrarySys.h>

namespace SourceMod

{

	class IExtensionInterface;

	/** 

	 * @brief Encapsulates an IExtension.

	 */

	class IExtension

	{

	public:

		/**

		 * @brief Returns whether or not the extension is properly loaded.

		 */

		virtual bool IsLoaded() =0;

		/**

		 * @brief Returns the extension's API interface

		 *

		 * @return			An IExtensionInterface pointer.

		 */

		virtual IExtensionInterface *GetAPI() =0;

		/**

		 * @brief Returns the filename of the extension, relative to the

		 * extension folder.

		 *

		 * @return			A string containing the extension file name.

		 */

		virtual const char *GetFilename() =0;

		/**

		 * @brief Returns the extension's identity token.

		 *

		 * @return			An IdentityToken_t pointer.

		 */

		virtual IdentityToken_t *GetIdentity() =0;

	};

	#define SMINTERFACE_EXTENSIONAPI_VERSION	1

	/**

	 * @brief The interface an extension must expose.

	 */

	class IExtensionInterface

	{

	public:

		/**

		 * @brief Called when the extension is loaded.

		 * 

		 * @param me		Pointer back to extension.

		 * @param sys		Pointer to interface sharing system of SourceMod.

		 * @param error		Error buffer to print back to, if any.

		 * @param err_max	Maximum size of error buffer.

		 * @param late		If this extension was loaded "late" (i.e. manually).

		 * @return			True if load should continue, false otherwise.

		 */

		virtual bool OnExtensionLoad(IExtension *me,

								  IShareSys *sys, 

								  char *error, 

								  size_t err_max, 

								  bool late) =0;

		/**

		 * @brief Called when the extension is about to be unloaded.

		 */

		virtual void OnExtensionUnload() =0;

		/**

		 * @brief Called when all extensions are loaded (loading cycle is done).

		 * If loaded late, this will be called right after OnExtensionLoad().

		 */

		virtual void OnExtensionsAllLoaded() =0;

		/**

		 * @brief Called when your pause state is about to change.

		 * 

		 * @param pause		True if pausing, false if unpausing.

		 */

		virtual void OnExtensionPauseChange(bool pause) =0;

		virtual unsigned int GetExtensionVersion()

		{

			return SMINTERFACE_EXTENSIONAPI_VERSION;

		}

		/**

		 * @brief Returns true if the extension is Metamod-dependent.

		 */

		virtual bool IsMetamodExtension() =0;

	public:

		virtual const char *GetExtensionName() =0;

		virtual const char *GetExtensionURL() =0;

		virtual const char *GetExtensionTag() =0;

		virtual const char *GetExtensionAuthor() =0;

		virtual const char *GetExtensionVerString() =0;

		virtual const char *GetExtensionDescription() =0;

		virtual const char *GetExtensionDateString() =0;

	};

	#define SMINTERFACE_EXTENSIONMANAGER_NAME			"IExtensionManager"

	#define SMINTERFACE_EXTENSIONMANAGER_VERSION		1

	enum ExtensionLifetime

	{

		ExtLifetime_Forever,			//Extension will never be unloaded automatically

		ExtLifetime_Map,				//Extension will be unloaded at the end of the map

	};

	class IExtensionManager : public SMInterface

	{

	public:

		virtual const char *GetInterfaceName()

		{

			return SMINTERFACE_EXTENSIONMANAGER_NAME;

		}

		virtual unsigned int GetInterfaceVersion()

		{

			return SMINTERFACE_EXTENSIONMANAGER_VERSION;

		}

	public:

		/**

		 * @brief Loads a extension into the extension system.

		 *

		 * @param path		Path to extension file, relative to the extensions folder.

		 * @param lifetime	Lifetime of the extension.

		 * @param error		Error buffer.

		 * @param err_max	Maximum error buffer length.

		 * @return			New IExtension on success, NULL on failure.

		 */

		virtual IExtension *LoadExtension(const char *path, 

									ExtensionLifetime lifetime, 

									char *error,

									size_t err_max) =0;

		/**

		 * @brief Returns the number of plugins that will be unloaded when this

		 * module is unloaded.

		 *

		 * @param pExt		IExtension pointer.

		 * @param optional	Optional pointer to be filled with # of plugins that 

		 *					are dependent, but will continue safely.  NOT YET USED.

		 * @return			Total number of dependent plugins.

		 */

		virtual unsigned int NumberOfPluginDependents(IExtension *pExt, unsigned int *optional) =0;

		/**

		 * @brief Returns whether or not the extension can be unloaded.

		 *

		 * @param pExt		IExtension pointer.

		 * @return			True if unloading is possible, false otherwise.

		 */

		virtual bool IsExtensionUnloadable(IExtension *pExtension) =0;

		/**

		 * @brief Attempts to unload a module.

		 *

		 * @param pExt		IExtension pointer.

		 * @return			True if successful, false otherwise.

		 */

		virtual bool UnloadExtension(IExtension *pExt) =0;

	};

};

#endif //_INCLUDE_SOURCEMOD_MODULE_INTERFACE_H_