PSpeaker.cxx

//==============================================================================
// File:        PSpeaker.cxx
//
// Copyright (c) 2017, Phil Harvey, Queen's University
//==============================================================================
#include <stdio.h>
#include <stdlib.h>
#include "PSpeaker.h"
#include "PListener.h"

const int   kListInc    = 10;

PSpeaker::PSpeaker()
{
    mListeners = NULL;
    mNumListeners = 0;
    mMaxListeners = 0;
}


PSpeaker::~PSpeaker()
{
    Speak(kMessageSpeakerDying, this);
    
    while (mNumListeners) {
        RemoveListener(*mListeners);
    }
    delete [] mListeners;
}


void PSpeaker::AddListener(PListener *aListener) 
{
    int i;
    
    // don't add a listener twice
    for (i=0; i<mNumListeners; ++i) {
        if (aListener == mListeners[i]) return;
    }
    /* add listener to this speaker's list */
    if (mNumListeners >= mMaxListeners) {
        PListener **tmp = new PListener*[mMaxListeners + kListInc];
        if (!tmp) {
            fprintf(stderr,"Out of memory in PSpeaker::AddListener\n");
            exit(1);
        }
        for (i=0; i<mNumListeners; ++i) tmp[i] = mListeners[i];
        delete [] mListeners;
        mListeners = tmp;
        mMaxListeners += kListInc;
    }
    mListeners[mNumListeners++] = aListener;
    
    /* add this speaker to listener's list */
    aListener->AddSpeaker(this);
}

void PSpeaker::RemoveListener(PListener *aListener)
{
    for (int i=0; i<mNumListeners; ++i) {
        if (aListener == mListeners[i]) {
            for (int j=i+1; j<mNumListeners; ++j) {
                mListeners[j-1] = mListeners[j];
            }
            --mNumListeners;
        }
    }
    
    /* remove this speaker from the listener's list */
    aListener->RemoveSpeaker(this);
}

void PSpeaker::Speak(int message, void *dataPt)
{
    for (int i=0; i<mNumListeners; ++i) {
        if (!mListeners[i]->IsIgnoring()) {
            mListeners[i]->Listen(message, dataPt);
        }
    }
}