#include "EXTERN.h"
#include "perl.h"
#include "XSUB.h"
#include "ppport.h"

#ifndef SDL_PERL_DEFINES_H
#include "defines.h"
#endif

#include <SDL.h>

#ifdef HAVE_SDL_MIXER
#include <SDL_mixer.h>

#define MAX_EFFECTS 31

PerlInterpreter *context = NULL;
int registered_effects   = 0;

void** effects = NULL;
void** effects_done = NULL;

char* effect_func_cb = NULL;
char* effect_func_done_cb = NULL;

void effect_func(int chan, void *stream, int len, void *udata)
{
	ENTER_TLS_CONTEXT;
	{
		dSP;                                       /* initialize stack pointer          */
		int i;
		Sint16 *buf = (Sint16 *)stream;

		len /= 2;            /* 2 bytes ber sample */

		ENTER;                                     /* everything created after here     */
		SAVETMPS;                                  /* ...is a temporary variable.       */

		PUSHMARK(SP);                              /* remember the stack pointer        */
		XPUSHs(sv_2mortal(newSViv(chan)));
		XPUSHs(sv_2mortal(newSViv(len)));
		XPUSHs(sv_2mortal(newSVsv(udata))); /* push something onto the stack     */
		for(i = 0; i < len; i++)
			XPUSHs(sv_2mortal(newSViv(buf[i])));

		PUTBACK;                                   /* make local stack pointer global   */

		/*if(cb != (SV*)NULL) */
		{
			int count = call_pv(effect_func_cb, G_ARRAY); /* call the function                 */
			SPAGAIN;                               /* refresh stack pointer             */

			if(count == len + 1)
				*(SV *)udata = *(newSVsv(POPs));

			if(count)
			{
				memset(buf, 0, len * 2); /* clear the buffer */

				for(i = len - 1; i >= 0; i--)
					buf[i] = POPi;
			}

			PUTBACK;
		}

		FREETMPS;                                  /* free that return value            */
		LEAVE;                                     /* ...and the XPUSHed "mortal" args. */
	}
	LEAVE_TLS_CONTEXT;
}

void effect_pm_func(void *udata, Uint8 *stream, int len)
{
	effect_func(-2, (void *)stream, len, udata);
}

void effect_done(int chan, void *udata)
{
	ENTER_TLS_CONTEXT;
	{
		dSP;     /* initialize stack pointer          */
		PUSHMARK(SP);                              /* remember the stack pointer        */
		call_pv(effect_func_done_cb, G_DISCARD|G_VOID);   /* call the function                 */
	}
	LEAVE_TLS_CONTEXT;
}

#endif

MODULE = SDL::Mixer::Effects 	PACKAGE = SDL::Mixer::Effects    PREFIX = mixeff_

#ifdef HAVE_SDL_MIXER

#ifdef USE_THREADS

int
mixeff_register(channel, func, done, arg)
	int channel
	char *func
	char *done
	SV *arg
	CODE:
		if(effects == NULL)
			effects = safemalloc(MAX_EFFECTS* sizeof(void*));
		if(effects_done == NULL)
			effects_done = safemalloc(MAX_EFFECTS* sizeof(void*));

		GET_TLS_CONTEXT;

		effect_func_cb      = func;
		effect_func_done_cb = done;
		if(registered_effects <= MAX_EFFECTS )
		{
			effects[registered_effects]      = (void *)&effect_func;
			effects_done[registered_effects] = (void *)&effect_done;
			if(0 != Mix_RegisterEffect(channel, effects[registered_effects], effects_done[registered_effects], arg))
			{
				/*warn( "Registered %d %p %p", registered_effects, effects[registered_effects], effects_done[registered_effects]); */
				RETVAL = registered_effects;
				registered_effects++;
			}
			else
			{
				warn( "Maximum effects allowed is 32 " );
				RETVAL = -1;
			}
		}
		else
			RETVAL = -1;
	OUTPUT:
		RETVAL

#else

int
mixeff_register(channel, func, done, arg)
	int channel
	char *func
	char *done
	SV *arg
	CODE:
		warn("Perl need to be compiled with 'useithreads' for SDL::Mixer::Effects::register( channel, func, done, arg )");
		XSRETURN_UNDEF;
	OUTPUT:
		RETVAL

#endif

int
mixeff_unregister( channel, func )
	int channel
	int func
	PREINIT:
		int check;
	CODE:
		if( func <= registered_effects)
		{
			check = Mix_UnregisterEffect(channel, effects[func]);
			if( check == 0 )
				warn ("Error unregistering: %s", Mix_GetError() );
		}
		else
		{
			warn (" Invalid effect id %d, currently %d effects registered", func, registered_effects);
			check = 0;
		}
		RETVAL = check;
	OUTPUT:
		RETVAL

int
mixeff_unregister_all( channel )
	int channel
	CODE:
		RETVAL = Mix_UnregisterAllEffects(channel);
	OUTPUT:
		RETVAL

int
mixeff_set_panning( channel, left, right )
	int channel
	int left
	int right
	CODE:
		RETVAL = Mix_SetPanning(channel, left, right);
	OUTPUT:
		RETVAL

int
mixeff_set_position( channel, angle, distance )
	int channel
	Sint16 angle
	Uint8 distance
	CODE:
		RETVAL = Mix_SetPosition(channel, angle, distance);
	OUTPUT:
		RETVAL

int
mixeff_set_distance( channel, distance )
	int channel
	Uint8 distance
	CODE:
		RETVAL = Mix_SetDistance(channel, distance);
	OUTPUT:
		RETVAL

int
mixeff_set_reverse_stereo( channel, flip )
	int channel
	Uint8 flip
	CODE:
		RETVAL = Mix_SetReverseStereo(channel, flip);
	OUTPUT:
		RETVAL

#ifdef USE_THREADS

void
mixeff_set_post_mix(func = NULL, arg = NULL)
	SV *func
	SV *arg
	CODE:
		GET_TLS_CONTEXT;
		if(func != (SV *)NULL)
			Mix_SetPostMix(&effect_pm_func, arg);
		else
			Mix_SetPostMix(NULL, NULL);

#else

void
mixeff_set_post_mix(func = NULL, arg = NULL)
	SV *func
	SV *arg
	CODE:
		warn("Perl need to be compiled with 'useithreads' for SDL::Mixer::Effects::set_post_mix( func, arg )");

#endif

#endif