/* Analog VU meter plugin for xmms
 *
 * Copyright (C) 2002 Pekka Harjamäki <analogvu@mcfish.org>
 *
 *  This program is free software; you can redistribute it and/or modify
 *  it under the terms of the GNU General Public License as published by
 *  the Free Software Foundation; either version 2 of the License, or
 *  (at your option) any later version.
 *
 *  This program is distributed in the hope that it will be useful,
 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *  GNU General Public License for more details.
 *
 *  You should have received a copy of the GNU General Public License
 *  along with this program; if not, write to the Free Software
 *  Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
 */

#include <gtk/gtk.h>
#include <gdk-pixbuf/gdk-pixbuf.h>

#include <math.h>
#include <stdio.h> 
#include <stdlib.h> 
#include <string.h> 
#include <sys/time.h>
#include <pthread.h>
 
#include <xmms/util.h>

#include "vumeter.h"

/*
 * Define external variables
 */

extern gint 		worker_running;
extern gint16 		shared_pcm_data[2][512];
extern GdkPixmap 	*doublebuf;
extern GtkWidget 	*area;
extern struct 		vumeter_cfg_info vumeter_cfg;
extern struct 		vumeter_skin_info vumeter_skin;

extern pthread_mutex_t 	pcm_data_lock;
extern float		left_needle_power[max_avarage_samples],
			right_needle_power[max_avarage_samples];

/****************************************
 * Worker thread
 ****************************************/

void *vumeter_worker(void *arg)
{
 long 	delay_value;
 int 	c, b=0; 
 float	max=32767.50,
 	db_min=(float)vumeter_skin.db_min_range,
 	channel_data[2]={0.0,0.0};
 struct timezone tz;
 struct timeval tv_cur,tv_past;

 // Set initial value
 gettimeofday(&tv_past,&tz);

 // Start thread loop
 while(worker_running>0)
 {
  do
  {
   // Test to see, if thread should shutdown
   if(worker_running==0) 
    pthread_exit(NULL);

   // Do we have new data packet waiting?
   if(worker_running==2)
   {
    // Reset values
    channel_data[0]=0.0;
    channel_data[1]=0.0;

    // Store value to make sure it does not change from now on..
    b=vumeter_cfg.av_samples;

    // Make sure, that data does not change
    if(pthread_mutex_trylock(&pcm_data_lock))
    {
     printf("Data race condition\n");
     pthread_mutex_lock(&pcm_data_lock);
    }

    // Process sound data
    for(c=0; c<512; c+=2)
    {
      channel_data[0]+=(float)(shared_pcm_data[0][c]*shared_pcm_data[0][c]);
      channel_data[1]+=(float)(shared_pcm_data[1][c]*shared_pcm_data[1][c]);
    }
    
    // Reset datapacket value
    if(worker_running==2) worker_running=1;

    // Release datalock
    pthread_mutex_unlock(&pcm_data_lock);

    // Calculate dBFS values for both channels using
    // avarage of 256 samples
    channel_data[0]=20*log10( sqrt(channel_data[0]/256.0) / max );
    channel_data[1]=20*log10( sqrt(channel_data[1]/256.0) / max );
  
    for(c=b; c>=1; c--)
    {
      left_needle_power[c]=left_needle_power[c-1];
     right_needle_power[c]=right_needle_power[c-1];
    }

    // Make sure, that value is never below db_min (default -91) dBFS
    if(channel_data[0]<db_min) 	left_needle_power[0]=db_min;
    			else	left_needle_power[0]=channel_data[0];
			
    if(channel_data[1]<db_min)	right_needle_power[0]=db_min;
    			else	right_needle_power[0]=channel_data[1];

   } // endIF (worker_running==2)
 
   xmms_usleep(1000);
   gettimeofday(&tv_cur,&tz);
   delay_value=(tv_cur.tv_sec-tv_past.tv_sec)*10000000+(tv_cur.tv_usec-tv_past.tv_usec);

  } while( delay_value < 18000 );

  // Must call gdk_thread_enter to make sure gtk+ does not mess anything up (we are now
  // in thread after all).. gdk_flush is called before releasing gtk+ mainloop lock
  gdk_threads_enter();
 	 gettimeofday(&tv_past,&tz);
	 if(doublebuf!=NULL && area!=NULL) gtk_widget_draw(area,NULL);
	 gdk_flush();
  gdk_threads_leave();

 } // endWHILE (worker_running>0)

 pthread_exit(NULL);
}