//
// Modified By:   Craig Stuart Sapp <craig@ccrma.stanford.edu>
// Creation Date: Fri Feb 28 18:41:42 PST 2003
// Last Modified: Sun Mar  9 12:16:33 PST 2003
// Filename:      floatmetro.c
// Source:        David Zicarelli: Writing External Objects for Max
//                4.0 and MSP 2.0, revision 11 (2001), pages 55-56
// Web Address:   http://peabody.sapp.org/class/dmp2/lab/floatmetro/floatmetro.c
// Syntax:        C; Max4/MSP2 External Object; CodeWarrior 6.0
// OS:            Mac OS 9; PPC
//
// Description:   Demonstration of event scheduling with a floating
//                point number input into the metro object.
//

#include "ext.h"

typedef struct {
   t_object max_data;  // must always be the first field; used by Max
   void*    clock;     // clock data structure pointer
   float    duration;  // duration between output bangs
   void*    output;    // pointer to outlet, need one for each outlet
} MyObject;

void* object_data;     // pointer to data for object (created in setup());

// function declarations:
void   main            (void);
void*  create_object   (float defaultDuration);
void   destroy_object  (MyObject *mo);
void   InputBang       (MyObject* mo);
void   InputInt        (MyObject* mo, long value);
void   InputDuration   (MyObject* mo, float value);
void   ClockTick       (MyObject *mo);
void   MessageStop     (MyObject *mo);
void   MessageStart    (MyObject *mo);


//////////////////////////////////////////////////////////////////////////
//
// Initialization functions:
//

void main(void) {
   setup((t_messlist**)&object_data, (method)create_object, 
         (method)destroy_object, (short)sizeof(MyObject), NULL, 
         A_DEFFLOAT, A_NOTHING);

   addbang((method)InputBang);
   addint((method)InputInt);
   addftx((method)InputDuration, 1);
   addmess((method)MessageStop, "stop", A_NOTHING);
   addmess((method)MessageStart, "start", A_NOTHING);
}



//////////////////////////////
//
// create_object -- 
//

void* create_object(float defaultInterval) {
   MyObject *mo = (MyObject*)newobject(object_data);
   mo->clock    = clock_new(mo, (method)ClockTick);
   if (defaultInterval < 20.0) {
      defaultInterval = 100.0;
   }
   mo->duration = defaultInterval;
   mo->output   = bangout(mo);
   floatin(mo, 1);
   return mo;
}



//////////////////////////////
//
// destroy_object -- what to do when the object is deleted from the patch.
//     In this case, you must free the clock object.
//

void destroy_object(MyObject *mo) {
   freeobject((t_object*)mo->clock);
}



//////////////////////////////////////////////////////////////////////////
//
// Behavior functions:
//


//////////////////////////////
//
// InputInt -- turn on the metronome when a non-zero positive value is
//      received, or turn it off when a zero or a negative value is received.
//

void InputInt(MyObject* mo, long value) {
   if (value > 0) {
      MessageStart(mo);
   } else {
      MessageStop(mo);
   }
}



//////////////////////////////
//
// InputBang -- What to do when a bang message arrives into the object:
//     if a bang is received from the object input, then send out a bang.
//

void InputBang(MyObject* mo) {
   MessageStart(mo);
}



//////////////////////////////
//
// InputDuration --
//

void InputDuration(MyObject* mo, float value) {
   if (value < 1.0) {
      value = 1.0;
   }
   mo->duration = value; 

}



//////////////////////////////
//
// ClockTick -- what to do when the event scheduler is ready.
//

void ClockTick(MyObject *mo) {
   clock_fdelay(mo->clock, mo->duration);  // schedule another metronome tick
   outlet_bang(mo->output);                // send out a bang message
}



//////////////////////////////
//
// MessageStop -- what to do when a "stop" message arrives
//

void MessageStop(MyObject *mo) {
   clock_unset(mo->clock);
}



//////////////////////////////
//
// MessageStart -- what to do when a "start" message arrives
//

void MessageStart(MyObject *mo) {
   clock_fdelay(mo->clock, 0.0);
}