/* ScummVM - Graphic Adventure Engine
 *
 * ScummVM is the legal property of its developers, whose names
 * are too numerous to list here. Please refer to the COPYRIGHT
 * file distributed with this source distribution.
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License
 * as published by the Free Software Foundation; either version 2
 * of the License, or (at your option) any later version.

 * 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.  See the
 * GNU General Public License for more details.

 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
 *
 * $URL$
 * $Id$
 *
 */

/* Sound engine */
#ifndef SCI_SFX_CORE_H
#define SCI_SFX_CORE_H

#include "common/error.h"
#include "sci/sfx/songlib.h"
#include "sci/resource.h"

namespace Sci {

class SongIterator;
struct fade_params_t;

#define SFX_TICKS_PER_SEC 60 /* MIDI ticks per second */


#define SFX_STATE_FLAG_MULTIPLAY (1 << 0) /* More than one song playable
** simultaneously ? */
#define SFX_STATE_FLAG_NOSOUND	 (1 << 1) /* Completely disable sound playing */

class SfxState {
public:	// FIXME, make private
	SongIterator *_it; /**< The song iterator at the heart of things */
	uint _flags; /**< SFX_STATE_FLAG_* */
	songlib_t _songlib; /**< Song library */
	song_t *_song; /**< Active song, or start of active song chain */
	bool _suspended; /**< Whether we are suspended */
	ResourceSync *_soundSync; /**< Used by kDoSync for speech syncing in CD talkie games */
	AudioResource *_audioResource; /**< Used for audio resources in CD talkie games */

public:
	SfxState();
	~SfxState();

	/***********/
	/* General */
	/***********/

	/* Initializes the sound engine
	** Parameters: (ResourceManager *) resmgr: Resource manager for initialization
	**             (int) flags: SFX_STATE_FLAG_*
	*/
	void sfx_init(ResourceManager *resmgr, int flags);

	/** Deinitializes the sound subsystem. */
	void sfx_exit();

	/* Suspends/unsuspends the sound sybsystem
	** Parameters: (int) suspend: Whether to suspend (non-null) or to unsuspend
	*/
	void sfx_suspend(bool suspend);

	/* Polls the sound server for cues etc.
	** Returns   : (int) 0 if the cue queue is empty, SI_LOOP, SI_CUE, or SI_FINISHED otherwise
	**             (song_handle_t) *handle: The affected handle
	**             (int) *cue: The sound cue number (if SI_CUE), or the loop number (if SI_LOOP)
	*/
	int sfx_poll(song_handle_t *handle, int *cue);

	/* Polls the sound server for cues etc.
	** Parameters: (song_handle_t) handle: The handle to poll
	** Returns   : (int) 0 if the cue queue is empty, SI_LOOP, SI_CUE, or SI_FINISHED otherwise
	**             (int) *cue: The sound cue number (if SI_CUE), or the loop number (if SI_LOOP)
	*/
	int sfx_poll_specific(song_handle_t handle, int *cue);

	/* Determines the current global volume settings
	** Returns   : (int) The global volume, between 0 (silent) and 127 (max. volume)
	*/
	int sfx_get_volume();

	/* Determines the current global volume settings
	** Parameters: (int) volume: The new global volume, between 0 and 127 (see above)
	*/
	void sfx_set_volume(int volume);

	/* Stops all songs currently playing, purges song library
	*/
	void sfx_all_stop();


	/*****************/
	/*  Song basics  */
	/*****************/

	/* Adds a song to the internal sound library
	** Parameters: (SongIterator *) it: The iterator describing the song
	**             (int) priority: Initial song priority (higher <-> more important)
	**             (song_handle_t) handle: The handle to associate with the song
	*/
	void sfx_add_song(SongIterator *it, int priority, song_handle_t handle, int resnum);


	/* Deletes a song and its associated song iterator from the song queue
	** Parameters: (song_handle_t) handle: The song to remove
	*/
	void sfx_remove_song(song_handle_t handle);


	/**********************/
	/* Song modifications */
	/**********************/


	/* Sets the song status, i.e. whether it is playing, suspended, or stopped.
	** Parameters: (song_handle_t) handle: Handle of the song to modify
	**             (int) status: The song status the song should assume
	** WAITING and PLAYING are set implicitly and essentially describe the same state
	** as far as this function is concerned.
	*/
	void sfx_song_set_status(song_handle_t handle, int status);

	/* Sets the new song priority
	** Parameters: (song_handle_t) handle: The handle to modify
	**             (int) priority: The priority to set
	*/
	void sfx_song_renice(song_handle_t handle, int priority);

	/* Sets the number of loops for the specified song
	** Parameters: (song_handle_t) handle: The song handle to reference
	**             (int) loops: Number of loops to set
	*/
	void sfx_song_set_loops(song_handle_t handle, int loops);

	/* Sets the number of loops for the specified song
	** Parameters: (song_handle_t) handle: The song handle to reference
	**             (int) hold: Number of loops to setn
	*/
	void sfx_song_set_hold(song_handle_t handle, int hold);

	/* Instructs a song to be faded out
	** Parameters: (song_handle_t) handle: The song handle to reference
	**             (fade_params_t *) fade_setup: The precise fade-out configuration to use
	*/
	void sfx_song_set_fade(song_handle_t handle, fade_params_t *fade_setup);


	// Previously undocumented:
	Common::Error sfx_send_midi(song_handle_t handle, int channel,
		int command, int arg1, int arg2);

protected:
	void freezeTime();
	void thawTime();

	bool isPlaying(song_t *song);
	void setSongStatus(song_t *song, int status);
	void updateSingleSong();
	void updateMultiSong();
	void update();
};


} // End of namespace Sci

#endif // SCI_SFX_CORE_H