//
// Copyright:     Copyright 2003 Craig Stuart Sapp
// Programmer:    Craig Stuart Sapp <craig@ccrma.stanford.edu>
// Creation Date: Sun Feb  9 10:51:25 PST 2003
// Last Modified: Sun Feb  9 10:54:37 PST 2003
// Filename:      polyflip.c
// Web Address:   http://peabody.sapp.org/class/dmp2/lab/flip/polyflip.c
// Syntax:        C; Max4/MSP2 External Object; CodeWarrior 6.0
// OS:	          Mac OS 9; PPC
//
// Description:   Flips the key number and duration of MIDI notes.
//

#include "ext.h"

typedef struct {
   t_object max_data;        // Max/MSP data, MUST come first in struct
   long     keymap[127];     // note mappings 
   long     velin;           // current 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     (void);
void    InputKeyNumber    (MyObject* mo, long value);
void    InputVelocity     (MyObject* mo, long value);
long    midilimit         (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_NOTHING);
   addint ((method)InputKeyNumber);      // inlet 1
   addinx ((method)InputVelocity,  1);   // inlet 2
}



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

void* create_object(void) {
   int i;
   MyObject* mo = (MyObject*)newobject(object_data);
   mo->velin = 0;
   for (i=0; i<128; i++) {
      mo->keymap[i] = 0;
   }
   mo->outputVelocity  = intout(mo);    // outlet 2
   mo->outputKeyNumber = intout(mo);    // outlet 1
   intin(mo, 1);                        // 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) {
      outlet_int(mo->outputVelocity, mo->velin);
      outlet_int(mo->outputKeyNumber, mo->keymap[value]);
   } else {
      outlet_int(mo->outputVelocity, value);
      outlet_int(mo->outputKeyNumber, mo->velin);
      mo->keymap[value] = midilimit(mo->velin);
   }
}



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

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


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


//////////////////////////////
//
// midilimit -- limit a number to the range from 0 to 127.
//    if the input is less than 0, return 0.  
//    if the input is greater than 127, return 127.  
//

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