//
// Copyright:     Copyright 2003 Craig Stuart Sapp
// Programmer:    Craig Stuart Sapp <craig@ccrma.stanford.edu>
// Creation Date: Thu Feb 13 18:37:54 PST 2003
// Last Modified: Sat Feb 15 13:28:17 PST 2003
// Filename:      snitch.c
// Web Address:   http://peabody.sapp.org/class/dmp2/lab/mirror/snitch.c
// Syntax:        C; Max4/MSP2 External Object; CodeWarrior 6.0
// OS:	          Mac OS 9; PPC
//
// Description:   Mirrors the notes according to the input mirror note.
//                The last note played is set to be the new mirror note.
//                The mirror note can be changed when there are
//                notes currently playing.  
//

#include "ext.h"

typedef struct {
   t_object max_data;        // Max/MSP data, MUST come first in struct
   long     states[128];     // note states for mirroring
   long     mirrornote;      // note number of the mirror 
   long     velin;           // temporary storage for input velocity
   void*    outputKeyNumber; // output the note number of the note
   void*    outputVelocity;  // output the duration of note in milliseconds
} MyObject;

void* object_data = NULL;

// function declarations:
void*   create_object     (long mirror);
void    InputKeyNumber    (MyObject* mo, long value);
void    InputVelocity     (MyObject* mo, long value);
void    InputMirror       (MyObject* mo, long value);


/////////////////////////////////////////////////////////////////////////
//
// Initialization functions
//

//////////////////////////////
//
// main -- called once when the object is created in a patcher window.
//

void main(void) {
   setup((t_messlist**)&object_data, (method)create_object,
         NULL, sizeof(MyObject), NULL, A_DEFLONG, A_NOTHING);
   addint ((method)InputKeyNumber);      // inlet 1
   addinx ((method)InputVelocity,  2);   // inlet 2
   addinx ((method)InputMirror,    1);   // inlet 3
}



//////////////////////////////
//
// create_object -- create the data storage for the mydiff object and
//     and setup input 1.
//

void* create_object(long initmirror) {
   MyObject* mo = (MyObject*)newobject(object_data);
   mo->mirror = initmirror;
   mo->velin  = 0;
   mo->outputVelocity  = intout(mo);    // outlet 2
   mo->outputKeyNumber = intout(mo);    // outlet 1
   intin(mo, 1);                        // inlet 3
   intin(mo, 2);                        // inlet 2
   return mo;
}


/////////////////////////////////////////////////////////////////////////
//
// Behavior functions
//


//////////////////////////////
//
// InputKeyNumber -- behavior of the object when a new number comes
//    in on inlet 1. 
//

void InputKeyNumber(MyObject* mo, long value) {
   value = midilimit(value);
   if (mo->velin == 0) {
      // turn off the last mirrored note for that key
      outlet_int(mo->outputVelocity, 0);
      outlet_int(mo->outputKeyNumber, mo->states[value]);
      mo->states[value] = 0;
   } else {
      if (mo->state[value] != 0) {
         // somehow a note was left on (perhaps non-MIDI keyboard)
         outlet_int(mo->outputVelocity, 0);
         outlet_int(mo->outputKeyNumber, mo->states[value]);
      }
      mo->states[value] = 2 * mo->mirrornote - value;
      outlet_int(mo->outputVelocity, mo->velin);
      outlet_int(mo->outputKeyNumber, mo->states[value]);
   }
   InputMirror(mo, value);
}



//////////////////////////////
//
// InputVelocity -- behavior of the object when a new number comes
//    in on inlet 2.  
//

void InputVelocity(MyObject* mo, long value) {
   mo->velin = value;
}



//////////////////////////////
//
// InputMirror -- input the mirror note.
//

void InputMirror(MyObject* mo, long value) {
   mo->mirrornote = value;
}



//////////////////////////////////////////////////////////////////////////
//
// Non-interface functions
//

//////////////////////////////
//
// midilimit -- limit data to the range from 0 to 127.
//

int midilimit(long value) {
   if (value < 0) return 0;
   if (value > 127) return 127;
   return value;
}