/*
  file: SpeechReclib.c
  author: Michael J. Norton
  date:  07/06/2000   oreillynet.com
  
  C source file contains the exported entries for initializing the 
  Apple Speech Recognition Manager.
  
  Requirements: Carbon SDK (available from www.apple.com Apple Developer Connection
*/
#include <CarbonEvents.h>
#include <Gestalt.h>
#include <SpeechRecognition.h>
#include <string.h>

#include "SpeechRecLib.h"




/* 
 * constants 
 */
const int          kBadSRMVersion = 100; 
const unsigned int kMinSRVersion = 0x00000150;   /* Minimum SR Version supported */


/* 
 * protected globals 
 */
SRRecognitionSystem objSRsystem     = NULL;     /* Object->SRRecognitionSystem */
SRRecognizer        objSRrecognizer = NULL;     /* Object->SRRecognizer */
SRLanguageModel     objSRtlm   = NULL;          /* Object->SRLanguageModel */


/* 
 * protected function entries 
 */
 
/*static pascal OSStatus SpeechEventHandler(AppleEvent *appleEvt, AppleEvent* reply, long refcon);*/
OSErr ProcessRecognitionResult (SRLanguageModel resultLM, SRRecognizer recognizer);
pascal OSErr MyHandleSpeechDone(AppleEvent *theAEevt, AppleEvent *reply, long refcon);

/*
 * Exported Entries to Initialize the Speech Recogniton Module 
 */


/* Speech Recognition Manager object constructor

    +----------------+       +---------------------+
    | SRSpeechObject |---+---| SRRecognitionSystem |  < objSRsystem >
    +----------------+   |   +---------------------+
                         |   +--------------+
                         +---| SRRecognizer |         < objSRrecognizer >
                             +--------------+
*/
OSStatus InitSpeech (void)
{

  OSStatus err;
  long  currVersion;
  short feedback = kSRHasFeedbackHasListenModes;
  
  /* check for valid Speech Recognition Manager */
  err = Gestalt(gestaltSpeechRecognitionVersion, &currVersion);
  if (!err)
  {
    if (currVersion < kMinSRVersion)
       return kBadSRMVersion;
  }
  
  /* instantiate the SR system object 
     
     +----------------+       +---------------------+
     | SRSpeechObject |---+---| SRRecognitionSystem |  < objSRsystem >
     +----------------+       +---------------------+
     
  */
     
  err = SROpenRecognitionSystem( &objSRsystem, kSRDefaultRecognitionSystemID);
     
  /* use standard feedback window and listening modes */
  if (!err)
    err = SRSetProperty(objSRsystem, kSRFeedbackAndListeningModes, &feedback, sizeof(feedback));  
  
 
  /* instantiate a Speech recognizer object
    +----------------+       +---------------------+
    | SRSpeechObject |---+---| SRRecognitionSystem |  < objSRsystem >
    +----------------+   |   +---------------------+
                         |   +--------------+
                         +---| SRRecognizer |         < objSRrecognizer >
                             +--------------+  
  
   */
  if (!err)
    err = SRNewRecognizer(objSRsystem, &objSRrecognizer, kSRDefaultSpeechSource);
    
  
  return err;
}

OSStatus CloseSpeech (void)
{

  OSStatus err = noErr;
  
  /* release the top language model 
  
    +----------------+       +---------------------+
    | SRSpeechObject |---+---| SRRecognitionSystem |   < objSRsystem >
    +----------------+   |   +---------------------+
                         |   +--------------+
                         +---| SRRecognizer |          < objSRrecognizer >
                             +--------------+  
                             +-----------------+   
                             | SRLanguageModel |->NULL < objSRtlm >
                             +-----------------+
  */
  if (objSRtlm)
  {
    err = SRReleaseObject(objSRtlm);
    objSRtlm = NULL;
  }
  
  /* release the recognizer object 
  
    +----------------+       +---------------------+
    | SRSpeechObject |---+---| SRRecognitionSystem |   < objSRsystem >
    +----------------+       +---------------------+
                             +--------------+
                             | SRRecognizer |->NULL    < objSRrecognizer *** >
                             +--------------+  
  */
  if (objSRrecognizer)
  {
    err = SRStopListening(objSRrecognizer);
    err = SRReleaseObject(objSRrecognizer);
    objSRrecognizer = NULL;
  }
  
  /* close the recognition system object
  
    +----------------+       +---------------------+
    | SRSpeechObject |       | SRRecognitionSystem |->NULL   < objSRsystem >
    +----------------+       +---------------------+

   */
  if (objSRsystem)
  {
    err = SRCloseRecognitionSystem(objSRsystem);
    objSRsystem = NULL;
  }
  
  return err;
}

OSStatus InitLanguageModel (const char kLangModelName[], const char *kRecWordList[], long topRefCon, long listRefcon)
{
  OSStatus err = noErr;
  
  /* initialize the language model 
    +----------------+       +---------------------+
    | SRSpeechObject |---+---| SRRecognitionSystem |       < objSRsystem >
    +----------------+   |   +---------------------+
                         |   +--------------+
                         +---| SRRecognizer |              < objSRrecognizer >
                         |   +--------------+  
                         |   +-----------------+   
                         +---| SRLanguageModel |-><Top LM> < objSRtlm >
                             +-----------------+ 
  
  */
  
  /* set the Top Languge Model */
  err = SRNewLanguageModel( objSRsystem, &objSRtlm, kLangModelName, strlen(kLangModelName) );
  /* assign the reference constant to this model. We will need it later when we process results */
  err = SRSetProperty( objSRtlm, kSRRefCon, &topRefCon, sizeof(topRefCon) );
  
  /* initialize the utterance list */
  if (!err)
  {
    char **currentStr = (char **) kRecWordList;
    
    while (*currentStr && !err) 
    {
      err = SRAddText(objSRtlm, *currentStr, strlen(*currentStr), listRefcon++);
      ++currentStr;
    }
  }
  return err;
}

OSStatus EnableSpeechModel (void)
{
  OSStatus err = noErr;
  
  /* attach the language model to the recognizer */
  err = SRSetLanguageModel(objSRrecognizer, objSRtlm);
  
  /* tell the recognizer to start listening */
  if (!err)
    err = SRStartListening(objSRrecognizer);
    
  return err;
}