/*____________________________________________________________________________
        
        FreeAmp - The Free MP3 Player

        MP3 Decoder originally Copyright (C) 1995-1997 Xing Technology
        Corp.  http://www.xingtech.com

        Portions Copyright (C) 1998-1999 EMusic.com

        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., 675 Mass Ave, Cambridge, MA 02139, USA.
        
        $Id: towave.c,v 1.8 2001/01/05 06:40:07 robert Exp $
____________________________________________________________________________*/

/* ------------------------------------------------------------------------

      NOTE NOTE NOTE NOTE NOTE NOTE NOTE NOTE NOTE NOTE NOTE NOTE NOTE

        This file exists for reference only. It is not actually used
        in the FreeAmp project. There is no need to mess with this 
        file. There is no need to flatten the beavers, either.

      NOTE NOTE NOTE NOTE NOTE NOTE NOTE NOTE NOTE NOTE NOTE NOTE NOTE
*/
/*---- towave.c --------------------------------------------
  32 bit version only

decode mpeg Layer I/II/III file using portable ANSI C decoder,
output to pcm wave file.

mod 8/19/98 decode 22 sf bands

mod 5/14/98  allow mpeg25 (dec8 not supported for mpeg25 samp rate)

mod 3/4/98 bs_trigger  bs_bufbytes  made signed, unsigned may 
            not terminate properly.  Also extra test in bs_fill.

mod 8/6/96 add 8 bit output to standard decoder

ver 1.4 mods 7/18/96 32 bit and add asm option

mods 6/29/95  allow MS wave file for u-law.  bugfix u-law table dec8.c

mods 2/95 add sample rate reduction, freq_limit and conversions.
          add _decode8 for 8Ks output, 16bit 8bit, u-law output.
          add additional control parameters to init.
          add _info function

mod 5/12/95 add quick window cwinq.c

mod 5/19/95 change from stream io to handle io

mod 11/16/95 add Layer I

mod 1/5/95   integer overflow mod iup.c

ver 1.3
mod 2/5/96   portability mods
             drop Tom and Gloria pcm file types

ver 2.0
mod 1/7/97   Layer 3 (float mpeg-1 only)
    2/6/97   Layer 3 MPEG-2

ver 3.01     Layer III bugfix crc problem 8/18/97
ver 3.02     Layer III fix wannabe.mp3 problem 10/9/97
ver 3.03     allow mpeg 2.5  5/14/98
  
Decoder functions for _decode8 are defined in dec8.c.  Useage
is same as regular decoder.

Towave illustrates use of decoder.  Towave converts
mpeg audio files to 16 bit (short) pcm.  Default pcm file
format is wave. Other formats can be accommodated by
adding alternative write_pcm_header and write_pcm_tailer
functions.  The functions kbhit and getch used in towave.c
may not port to other systems.

The decoder handles all mpeg1 and mpeg2 Layer I/II  bitstreams.  

For compatability with the asm decoder and future C versions,
source code users are discouraged from making modifications
to the decoder proper.  MS Windows applications can use wrapper
functions in a separate module if decoder functions need to
be exported.

NOTE additional control parameters.

mod 8/6/96 standard decoder adds 8 bit output

decode8 (8Ks output) convert_code:
   convert_code = 4*bit_code + chan_code
       bit_code:   1 = 16 bit linear pcm
                   2 =  8 bit (unsigned) linear pcm
                   3 = u-law (8 bits unsigned)
       chan_code:  0 = convert two chan to mono
                   1 = convert two chan to mono
                   2 = convert two chan to left chan
                   3 = convert two chan to right chan

decode (standard decoder) convert_code:
             0 = two chan output
             1 = convert two chan to mono
             2 = convert two chan to left chan
             3 = convert two chan to right chan
     or with 8 = 8 bit output 
          (other bits ignored)

decode (standard decoder) reduction_code:
             0 = full sample rate output
             1 = half rate
             2 = quarter rate

-----------------------------------------------------------*/
#include <stdlib.h>
#include <stdio.h>
#include <float.h>
#include <math.h>
#include <string.h>
#include <errno.h>
//#include <unistd.h>
#ifdef WIN32
#include <io.h>
#endif
#include <fcntl.h>              /* file open flags */
#include <sys/types.h>          /* someone wants for port */
#include <sys/stat.h>           /* forward slash for portability */
#include "mhead.h"              /* mpeg header structure, decode protos */

#define NEED_KBHIT

#include "port.h"

/* time test Pentium only */
//#define TIME_TEST

static char default_file[] = "TEST.MP3";
static char default_outfile[] = "TEST.WAV";

/*---- timing test ---*/
#ifdef TIME_TEST
static double tot_cycles;
static int tot_cycles_n;
unsigned int set_clock(void);
unsigned int get_clock(void);
extern unsigned int global_cycles;

#endif

float     equalizer[32] = {
   1.0, 1.0, 1.0, 1.0, 1.0, 1.0, 1.0, 1.0,
   1.0, 1.0, 1.0, 1.0, 1.0, 1.0, 1.0, 1.0,
   1.0, 1.0, 1.0, 1.0, 1.0, 1.0, 1.0, 1.0,
   1.0, 1.0, 1.0, 1.0, 1.0, 1.0, 1.0, 1.0,
};
int       enableEQ = 0;
float     EQ_gain_adjust = 1.0;

/*********  bitstream buffer */
#define BS_BUFBYTES 60000U
static unsigned char *bs_buffer = NULL;
static unsigned char *bs_bufptr;
static int bs_trigger;
static int bs_bufbytes;
static int handle = -1;

/********************** */

/********  pcm buffer ********/
#define PCM_BUFBYTES  60000U
static char *pcm_buffer;
static unsigned int pcm_bufbytes;
static unsigned int pcm_trigger = (PCM_BUFBYTES - 2500 * sizeof(short));
static int handout = -1;

/****************************/
static int bs_fill();

static int out_help();
static int out_mpeg_info(MPEG_HEAD * h, int bitrate_arg);
int       ff_decode(char *filename,

                    char *fileout,
                    int reduction_code,
                    int convert_code,
                    int decode8_flag, int freq_limit, int integer_decode);
int       cvt_to_wave_test();
int       write_pcm_header_wave(int handout,
                                int samprate, int channels, int bits, int type);
int       write_pcm_tailer_wave(int handout, unsigned int pcm_bytes);

/*------------------------------------------*/
int
main(int argc, char *argv[])
{
   int       i, k;
   char     *filename;
   char     *fileout;
   int       convert_code;
   int       reduction_code;
   int       freq_limit;
   int       integer_decode;
   int       decode8_flag;      /* decode to 8KHz */

   printf("\n  file-file MPEG Layer I/II/III audio decode v3.04/32"
          "\n Copyright 1995-98 Xing Technology Corp."
          "\n"
          "\n useage: towave mpeg_file pcm_file -Cconvert_code -Rreduction_code"
          "\n                 -I -D8 -HELP ");

/****** process command line args */
   filename = default_file;
   fileout = default_outfile;
   convert_code = 0;
   reduction_code = 0;
   freq_limit = 24000;
   integer_decode = 0;
   decode8_flag = 0;            /* decode to 8KHz */
   for (k = 0, i = 1; i < argc; i++)
   {
      if (argv[i][0] != '-')
      {
         if (k == 0)
            filename = argv[i];
         if (k == 1)
            fileout = argv[i];
         k++;
         continue;
      }
      switch (argv[i][1])
      {
      case 'h':
      case 'H':
         out_help();
         return 0;
      case 'c':
      case 'C':
         convert_code = atoi(argv[i] + 2);
         break;
      case 'r':
      case 'R':
         reduction_code = atoi(argv[i] + 2);
         break;
      case 'f':
      case 'F':
         freq_limit = atoi(argv[i] + 2);
         break;
      case 'i':
      case 'I':
         integer_decode = 1;
         break;
      case 'd':
      case 'D':
         if (atoi(argv[i] + 2) == 8)
            decode8_flag = 1;
         break;
      }
   }

   printf("\n  <press any key to stop decoder>");

/******** decode *********/
   ff_decode(filename, fileout,
             reduction_code, convert_code, decode8_flag,
             freq_limit, integer_decode);
/*************************/

/*---- timing test --------*/
#ifdef TIME_TEST
   if (tot_cycles_n)
   {
      // ms per frame
      tot_cycles = (1.0 / 266000.0) * tot_cycles / tot_cycles_n;
      if (tot_cycles > 5.0)
         printf("\n ave frame time ms = %8.1lf", tot_cycles);
      else
         printf("\n ave frame time ms = %8.2lf", tot_cycles);
   }
#endif

   printf("\n");
   return 0;
}

/*-------------------------------------------------------------*/
static int
out_help()
{

   printf("\n"
          "\n -D8 option decode8 (8Ks output) convert_code:"
          "\n    convert_code = 4*bit_code + chan_code"
          "\n        bit_code:   1 = 16 bit linear pcm"
          "\n                    2 =  8 bit (unsigned) linear pcm"
          "\n                    3 = u-law (8 bits unsigned)"
          "\n        chan_code:  0 = convert two chan to mono"
          "\n                    1 = convert two chan to mono"
          "\n                    2 = convert two chan to left chan"
          "\n                    3 = convert two chan to right chan"
          "\n decode (standard decoder) convert_code:"
          "\n              0 = two chan output"
          "\n              1 = convert two chan to mono"
          "\n              2 = convert two chan to left chan"
          "\n              3 = convert two chan to right chan"
          "\n              (higher bits ignored)"
          "\n decode (standard decoder) reduction_code:"
          "\n              0 = full sample rate output"
          "\n              1 = half rate"
          "\n              2 = quarter rate"
          "\n -I  option selects integer decoder");

   return 1;
}

/*-------------------------------------------------------------*/
int
ff_decode(char *filename, char *fileout,
          int reduction_code, int convert_code, int decode8_flag,
          int freq_limit, int integer)
{
   int       framebytes;
   int       u;
   MPEG_HEAD head;
   MPEG      m;
   unsigned int nwrite;
   IN_OUT    x;
   int       in_bytes, out_bytes;
   DEC_INFO  decinfo;
   int       bitrate;

/*------------------------------------------*/
/*   typedef struct
   {
      int (*decode_init) (MPEG_HEAD * h, int framebytes_arg,
                          int reduction_code, int transform_code,
                          int convert_code, int freq_limit);
      void (*decode_info) (DEC_INFO * info);
        IN_OUT(*decode) (unsigned char *bs, short *pcm);
   }
   AUDIO;
   static AUDIO audio;
   static AUDIO audio_table[2][2] =
   {
      {
         {audio_decode_init, audio_decode_info, audio_decode},
         {audio_decode8_init, audio_decode8_info, audio_decode8},
      },
      {
         {i_audio_decode_init, i_audio_decode_info, i_audio_decode},
         {audio_decode8_init, audio_decode8_info, audio_decode8},
      }
   };
*/
/*------------------------------------------*/

/*-----------------------*/
   printf("\nMPEG input file: %s", filename);
   printf("\n    output file: %s", fileout);
/*-----------------------*/
/*-----select decoder --------------*/
/*   if (decode8_flag && (convert_code >= 4))
      audio = audio_table[integer & 1][1];
   else
      audio = audio_table[integer & 1][0]; */
/*-----------------------*/

   mpeg_init(&m, 1);
   in_bytes = out_bytes = 0;
/*-----------------------*/
   handout = -1;
   pcm_buffer = NULL;
   pcm_bufbytes = 0;
/*-----------------------*/
   bs_buffer = NULL;
   handle = -1;
   bs_bufbytes = 0;
   bs_bufptr = bs_buffer;
   bs_trigger = 2500;
/*--- test for valid cvt_to_wave compile ---*/
   if (cvt_to_wave_test() != 0)
   {
      printf("\n INVALID CVT_TO_WAVE COMPILE");
      goto abort;
   }
/*------ open mpeg file --------*/
   handle = open(filename, O_RDONLY | O_BINARY);
   if (handle < 0)
   {
      printf("\n CANNOT_OPEN_INPUT_FILE\n");
      goto abort;
   }
/*--- allocate bs buffer ----*/
   bs_buffer = malloc(BS_BUFBYTES);
   if (bs_buffer == NULL)
   {
      printf("\n CANNOT_ALLOCATE_BUFFER\n");
      goto abort;
   }
/*--- fill bs buffer ----*/
   if (!bs_fill())
      goto abort;
/*---- parse mpeg header  -------*/
   framebytes = head_info2(bs_buffer, bs_bufbytes, &head, &bitrate);
   if (framebytes == 0)
   {
      printf("\n BAD OR UNSUPPORTED MPEG FILE\n");
      goto abort;
   }
/*--- display mpeg info --*/
   out_mpeg_info(&head, bitrate);

/*---- create pcm file ------*/
   handout =
      open(fileout, O_RDWR | O_BINARY | O_CREAT | O_TRUNC, S_IREAD | S_IWRITE);
   handout = open(fileout, O_WRONLY | O_BINARY);
/*
   {
       int fd;
       int channels = 2;
       int play_precision = 16;
       int play_stereo = channels-1;
       int play_sample_rate = 44100; //info->samples_per_second;
       int junkvar = 0;
       int flags;
       if ((fd = open("/dev/dsp", O_WRONLY | O_SYNC, 0)) < 0) {
           if (errno == EBUSY) {
               printf("Audio device busy!\n");
               exit(1);
           } else {
               printf("Can't open /dev/dsp for writing");
               exit(1);
           }
       }
       
       if ((flags = fcntl(fd,F_GETFL,0)) < 0) {
           printf("fcntl F_GETFL on /dev/audio failed");
           exit(1);
       }
       flags &= ~O_NDELAY;
       
       if (fcntl(fd, F_SETFL, flags) < 0) {
           printf("fcntl F_SETFL on /dev/audio failed");
           exit(1);
       }
       
       handout = fd;

       
       if (handout < 0) {
           printf ("Internal error, LinuxObuffer::handout has to be initialized\nby LinuxObuffer::class_suitable()!\n");
           exit (1);
       }
       
       // configure the device:
       //int play_precision = 16;
       //int play_stereo = channels-1;
       //int play_sample_rate = info->samples_per_second;
       //int junkvar = 0;
       if (ioctl(handout, SNDCTL_DSP_RESET, &junkvar) == -1) {
           printf("hosed during ioctl reset\n");
           exit(1);
       } 
       
       if(ioctl(handout, SNDCTL_DSP_SAMPLESIZE, &play_precision) == -1) {
           printf("config of samplesize failed");
           exit(1);
       }
       if(ioctl(handout, SNDCTL_DSP_STEREO, &play_stereo) == -1) {
           printf("config of stereo failed");
           exit(1);
       }
       if (ioctl(handout, SNDCTL_DSP_SPEED, &play_sample_rate) == -1) {
           printf("config of speed failed");
           exit(1);
       }
       
   }
*/
   if (handout < 0)
   {
      printf("\n CANNOT CREATE OUTPUT FILE\n");
      goto abort;
   }
/*---- allocate pcm buffer --------*/
   pcm_buffer = malloc(PCM_BUFBYTES);
   if (pcm_buffer == NULL)
   {
      printf("\n CANNOT ALLOCATE PCM BUFFER\n");
      goto abort;
   }

/*---- init decoder -------*/
   if (!audio_decode_init(&m, &head, framebytes,
                          reduction_code, 0, convert_code, freq_limit))
   {
      printf("\n DECODER INIT FAIL \n");
      goto abort;
   }
/*---- get info -------*/
   audio_decode_info(&m, &decinfo);
/*---- info display -------*/
   printf("\n output samprate = %6ld", decinfo.samprate);
   printf("\n output channels = %6d", decinfo.channels);
   printf("\n output bits     = %6d", decinfo.bits);
   printf("\n output type     = %6d", decinfo.type);

/*---- write pcm header -------*/
   if (!write_pcm_header_wave(handout,
                              decinfo.samprate, decinfo.channels, decinfo.bits,
                              decinfo.type))
   {
      printf("\n FILE WRITE ERROR\n");
      goto abort;
   }

/*--- init wave converter ---*/
   cvt_to_wave_init(decinfo.bits);

   printf("\n");
/*----- DECODE -----*/

   for (u = 0;;)
   {
      if (!bs_fill())
         break;
      if (bs_bufbytes < framebytes)
         break;                 /* end of file */
#ifdef TIME_TEST
      set_clock();
#endif
      x = audio_decode(&m, bs_bufptr, (short *) (pcm_buffer + pcm_bufbytes));
#ifdef TIME_TEST
      get_clock();
      tot_cycles += global_cycles;
      tot_cycles_n++;
#endif
      if (x.in_bytes <= 0)
      {
         printf("\n BAD SYNC IN MPEG FILE\n");
         break;
      }
      bs_bufptr += x.in_bytes;
      bs_bufbytes -= x.in_bytes;
      pcm_bufbytes += x.out_bytes;
      u++;
      if (pcm_bufbytes > pcm_trigger)
      {
         pcm_bufbytes = cvt_to_wave(pcm_buffer, pcm_bufbytes);
         do
         {
            nwrite = write(handout, pcm_buffer, pcm_bufbytes);
            usleep(10000);
         }
         while (errno == EAGAIN);
         if (nwrite != pcm_bufbytes)
         {
            printf("\n FILE WRITE ERROR\n");
            break;
         }
         out_bytes += pcm_bufbytes;
         pcm_bufbytes = 0;
      }
      if (kbhit())
         break;
      in_bytes += x.in_bytes;
      if ((u & 63) == 1)
         printf("\r frames %6ld   bytes in %6ld    bytes out %6ld",
                u, in_bytes, out_bytes);
   }
/*---------------*/

   if (pcm_bufbytes > 0)
   {
      pcm_bufbytes = cvt_to_wave(pcm_buffer, pcm_bufbytes);
      nwrite = write(handout, pcm_buffer, pcm_bufbytes);
      if (nwrite != pcm_bufbytes)
      {
         printf("\n FILE WRITE ERROR\n");
      }
      out_bytes += pcm_bufbytes;
      pcm_bufbytes = 0;
   }
   printf("\n frames %6ld   bytes in %6ld    bytes out %6ld",
          u, in_bytes, out_bytes);

/*---- write pcm tailer -------*/
   write_pcm_tailer_wave(handout, out_bytes);

   printf("\n    output file: %s", fileout);

 abort:
   mpeg_cleanup(&m);
   close(handle);
   close(handout);
   free(bs_buffer);
   free(pcm_buffer);
   while (kbhit())
      getch();                  /* purge key board */
   return 1;
}

/*-------------------------------------------------------------*/
static int
bs_fill()
{
   unsigned int nread;

   if (bs_bufbytes < 0)
      bs_bufbytes = 0;          // signed var could be negative

   if (bs_bufbytes < bs_trigger)
   {
      memmove(bs_buffer, bs_bufptr, bs_bufbytes);
      nread = read(handle, bs_buffer + bs_bufbytes, BS_BUFBYTES - bs_bufbytes);
      if ((nread + 1) == 0)
      {
/*-- test for -1 = error --*/
         bs_trigger = 0;
         printf("\n FILE_READ_ERROR\n");
         return 0;
      }
      bs_bufbytes += nread;
      bs_bufptr = bs_buffer;
   }

   return 1;
}

/*------------------------------------------------------------------*/
static int
out_mpeg_info(MPEG_HEAD * h, int bitrate_arg)   /* info only */
{
   int       bitrate;
   int       samprate;
   static char *Layer_msg[] = { "INVALID", "III", "II", "I" };
   static char *mode_msg[] = { "STEREO", "JOINT", "DUAL", "MONO" };
   static int sr_table[8] = { 22050L, 24000L, 16000L, 1L,
      44100L, 48000L, 32000L, 1L
   };

   bitrate = bitrate_arg / 1000;
   printf("\n Layer %s ", Layer_msg[h->option]);

   printf("  %s ", mode_msg[h->mode]);
   samprate = sr_table[4 * h->id + h->sr_index];
   if ((h->sync & 1) == 0)
      samprate = samprate / 2;  // mpeg25

   printf(" %d ", samprate);
   printf("  %dKb ", bitrate);
   if ((h->mode == 1) && (h->option != 1))
      printf("  %d stereo bands ", 4 + 4 * h->mode_ext);
   if (h->prot == 0)
      printf(" (CRC)");

   return 0;
}

/*------------------------------------------------------------------*/
int
dummy()
{
   return 0;
}
