/*
	the long waited for swap~-object that does a byte swap
	of course, we unfortunately have to quantize the float-signal to 16bit (to get bytes)

	1110:forum::für::umläute:1999
  */

#include "zexy.h"
#ifdef NT
#pragma warning( disable : 4244 )
#pragma warning( disable : 4305 )
#endif

/* ------------------------ swap~ ----------------------------- */
#define FLOAT2SHORT 32768.
#define SHORT2FLOAT 1./32768.

static t_class *swap_class;

typedef struct _swap
{
    t_object x_obj;
	int swapper;
} t_swap;

static void swap_float(t_swap *x, t_floatarg f)
{
	x->swapper = (f != 0);
}

static void swap_bang(t_swap *x)
{
	x->swapper ^= 1;
}

static t_int *swap_perform(t_int *w)
{
	t_swap	*x = (t_swap *)(w[1]);
    t_float *in = (t_float *)(w[2]);
    t_float *out = (t_float *)(w[3]);
    int n = (int)(w[4]);


	if (x->swapper) 
		while (n--) {
			short dummy = FLOAT2SHORT * *in++;
			*out++ = SHORT2FLOAT * (short)( ((dummy & 0xFF) << 8) | ((dummy & 0xFF00) >> 8) );
		}
	else while (n--) *out++ = *in++;

	return (w+5);
}

static void swap_dsp(t_swap *x, t_signal **sp)
{
    dsp_add(swap_perform, 4, x, sp[0]->s_vec, sp[1]->s_vec, sp[0]->s_n);
}

static void helper(void)
{
	post("\n%c swap~-object for byteswapping a signal", HEARTSYMBOL);
	post("<1/0>  : turn the swapper on/off\n"
		"'bang' : toggle the swapper on/off\n"
		"'help' : view this\n"
		"signal~");
	post("outlet : signal~");
}

static void *swap_new()
{
    t_swap *x = (t_swap *)pd_new(swap_class);
    outlet_new(&x->x_obj, gensym("signal"));
	x->swapper = 1;
    return (x);
}

void z_swap_setup(void)
{
    swap_class = class_new(gensym("swap~"), (t_newmethod)swap_new, 0,
    	sizeof(t_swap), 0, A_DEFFLOAT, 0);
    class_addmethod(swap_class, nullfn, gensym("signal"), 0);
    class_addmethod(swap_class, (t_method)swap_dsp, gensym("dsp"), 0);

	class_addfloat(swap_class, swap_float);
	class_addbang(swap_class, swap_bang);

    class_addmethod(swap_class, (t_method)helper, gensym("help"), 0);
	class_sethelpsymbol(swap_class, gensym("zexy/swap~"));
}