/* @(#)cd_text.c	1.5 03/12/31 Copyright 2000-2001 Heiko Eissfeldt */

/* This is an include file! */
/**************** CD-Text special treatment **********************************/

typedef struct {
	unsigned char headerfield[4];
	unsigned char textdatafield[12];
	unsigned char crcfield[2];
} cdtextpackdata;

static unsigned short crctab[1<<8] = { /* as calculated by initcrctab() */
    0x0000,  0x1021,  0x2042,  0x3063,  0x4084,  0x50a5,  0x60c6,  0x70e7,
    0x8108,  0x9129,  0xa14a,  0xb16b,  0xc18c,  0xd1ad,  0xe1ce,  0xf1ef,
    0x1231,  0x0210,  0x3273,  0x2252,  0x52b5,  0x4294,  0x72f7,  0x62d6,
    0x9339,  0x8318,  0xb37b,  0xa35a,  0xd3bd,  0xc39c,  0xf3ff,  0xe3de,
    0x2462,  0x3443,  0x0420,  0x1401,  0x64e6,  0x74c7,  0x44a4,  0x5485,
    0xa56a,  0xb54b,  0x8528,  0x9509,  0xe5ee,  0xf5cf,  0xc5ac,  0xd58d,
    0x3653,  0x2672,  0x1611,  0x0630,  0x76d7,  0x66f6,  0x5695,  0x46b4,
    0xb75b,  0xa77a,  0x9719,  0x8738,  0xf7df,  0xe7fe,  0xd79d,  0xc7bc,
    0x48c4,  0x58e5,  0x6886,  0x78a7,  0x0840,  0x1861,  0x2802,  0x3823,
    0xc9cc,  0xd9ed,  0xe98e,  0xf9af,  0x8948,  0x9969,  0xa90a,  0xb92b,
    0x5af5,  0x4ad4,  0x7ab7,  0x6a96,  0x1a71,  0x0a50,  0x3a33,  0x2a12,
    0xdbfd,  0xcbdc,  0xfbbf,  0xeb9e,  0x9b79,  0x8b58,  0xbb3b,  0xab1a,
    0x6ca6,  0x7c87,  0x4ce4,  0x5cc5,  0x2c22,  0x3c03,  0x0c60,  0x1c41,
    0xedae,  0xfd8f,  0xcdec,  0xddcd,  0xad2a,  0xbd0b,  0x8d68,  0x9d49,
    0x7e97,  0x6eb6,  0x5ed5,  0x4ef4,  0x3e13,  0x2e32,  0x1e51,  0x0e70,
    0xff9f,  0xefbe,  0xdfdd,  0xcffc,  0xbf1b,  0xaf3a,  0x9f59,  0x8f78,
    0x9188,  0x81a9,  0xb1ca,  0xa1eb,  0xd10c,  0xc12d,  0xf14e,  0xe16f,
    0x1080,  0x00a1,  0x30c2,  0x20e3,  0x5004,  0x4025,  0x7046,  0x6067,
    0x83b9,  0x9398,  0xa3fb,  0xb3da,  0xc33d,  0xd31c,  0xe37f,  0xf35e,
    0x02b1,  0x1290,  0x22f3,  0x32d2,  0x4235,  0x5214,  0x6277,  0x7256,
    0xb5ea,  0xa5cb,  0x95a8,  0x8589,  0xf56e,  0xe54f,  0xd52c,  0xc50d,
    0x34e2,  0x24c3,  0x14a0,  0x0481,  0x7466,  0x6447,  0x5424,  0x4405,
    0xa7db,  0xb7fa,  0x8799,  0x97b8,  0xe75f,  0xf77e,  0xc71d,  0xd73c,
    0x26d3,  0x36f2,  0x0691,  0x16b0,  0x6657,  0x7676,  0x4615,  0x5634,
    0xd94c,  0xc96d,  0xf90e,  0xe92f,  0x99c8,  0x89e9,  0xb98a,  0xa9ab,
    0x5844,  0x4865,  0x7806,  0x6827,  0x18c0,  0x08e1,  0x3882,  0x28a3,
    0xcb7d,  0xdb5c,  0xeb3f,  0xfb1e,  0x8bf9,  0x9bd8,  0xabbb,  0xbb9a,
    0x4a75,  0x5a54,  0x6a37,  0x7a16,  0x0af1,  0x1ad0,  0x2ab3,  0x3a92,
    0xfd2e,  0xed0f,  0xdd6c,  0xcd4d,  0xbdaa,  0xad8b,  0x9de8,  0x8dc9,
    0x7c26,  0x6c07,  0x5c64,  0x4c45,  0x3ca2,  0x2c83,  0x1ce0,  0x0cc1,
    0xef1f,  0xff3e,  0xcf5d,  0xdf7c,  0xaf9b,  0xbfba,  0x8fd9,  0x9ff8,
    0x6e17,  0x7e36,  0x4e55,  0x5e74,  0x2e93,  0x3eb2,  0x0ed1,  0x1ef0,
    };

#define SUBSIZE	18*8

static unsigned short updcrc __PR((
	    unsigned int    p_crc,
            register unsigned char   *cp,
            register size_t  cnt));

static unsigned short updcrc(p_crc, cp, cnt)
	unsigned int p_crc;
        register unsigned char   *cp;
        register size_t  cnt;
{
      register unsigned short crc = (unsigned short)p_crc;
      while( cnt-- ) {
            crc = (crc<<8) ^ crctab[(crc>>(16-8)) ^ (*cp++)];
      }
      return( crc );
}

static unsigned short calcCRC __PR((unsigned char *buf, unsigned bsize));

static unsigned short calcCRC(buf, bsize)
	unsigned char *buf;
	unsigned bsize;
{
      return updcrc( 0x0, (unsigned char *)buf, bsize );
}

static unsigned char    fliptab[8] = {
        0x01,
        0x02,
        0x04,
        0x08,
        0x10,
        0x20,
        0x40,
        0x80,
};

static int flip_error_corr __PR((unsigned char *b, int crc));

static int flip_error_corr(b, crc)
	unsigned char *b;
	int crc;
{
  if (crc != 0) {
    int i;
    for (i = 0; i < SUBSIZE; i++) {
      char      c;

      c = fliptab[i%8];
      b[i / 8] ^= c;
      if ((crc = calcCRC(b, SUBSIZE/8)) == 0) {
        return crc;
      }
      b[i / 8] ^= c;
    }
  }
  return crc & 0xffff;
}


static int cdtext_crc_ok __PR((cdtextpackdata *c));

static int cdtext_crc_ok (c)
	cdtextpackdata *c;
{
	int crc;
	int retval;

	c->crcfield[0] ^= 0xff;
	c->crcfield[1] ^= 0xff;
	crc = calcCRC(((unsigned char *)c), 18);
	retval = (0 == flip_error_corr((unsigned char *)c, crc));
	c->crcfield[0] ^= 0xff;
	c->crcfield[1] ^= 0xff;
#if	0
          fprintf(stderr, "%02x %02x %02x %02x  ",
                          c->headerfield[0], c->headerfield[1], c->headerfield[2], c->headerfield[3]);
          fprintf(stderr,
"%c %c %c %c %c %c %c %c %c %c %c %c  "
                        , c->textdatafield[0]
                        , c->textdatafield[1]
                        , c->textdatafield[2]
                        , c->textdatafield[3]
                        , c->textdatafield[4]
                        , c->textdatafield[5]
                        , c->textdatafield[6]
                        , c->textdatafield[7]
                        , c->textdatafield[8]
                        , c->textdatafield[9]
                        , c->textdatafield[10]
                        , c->textdatafield[11]
                 );
          fprintf(stderr, "%02x %02x \n"
                        , c->crcfield[0]
                        , c->crcfield[1]
		);
#endif
	return retval;
}

#define DETAILED 0

#if	DETAILED
static void dump_binary __PR((cdtextpackdata *c));

static void dump_binary(c)
	cdtextpackdata *c;
{
          fprintf(stderr, ": header fields %02x %02x %02x  ",
                          c->headerfield[1], c->headerfield[2], c->headerfield[3]);
          fprintf(stderr,
"%02x %02x %02x %02x %02x %02x %02x %02x %02x %02x %02x %02x"
                        , c->textdatafield[0]
                        , c->textdatafield[1]
                        , c->textdatafield[2]
                        , c->textdatafield[3]
                        , c->textdatafield[4]
                        , c->textdatafield[5]
                        , c->textdatafield[6]
                        , c->textdatafield[7]
                        , c->textdatafield[8]
                        , c->textdatafield[9]
                        , c->textdatafield[10]
                        , c->textdatafield[11]
                 );
}
#endif

static int process_header __PR((cdtextpackdata *c, unsigned tracknr, int dbcc, unsigned char *line));

static int process_header(c, tracknr, dbcc, line)
	cdtextpackdata *c;
	unsigned tracknr;
	int dbcc;
	unsigned char *line;
{
      switch ((int)c->headerfield[0]) {

        case 0x80: /* Title of album or track */
#if	DETAILED
          fprintf (stderr, "Title");
#endif
	  if (tracknr > 0 && tracknr < 100
	    && global.tracktitle[tracknr] == NULL) {
	    unsigned len;

	    len = strlen((char *)line);

            if (len > 0)
            	global.tracktitle[tracknr] = malloc(len + 1);
            if (global.tracktitle[tracknr] != NULL) {
               memcpy(global.tracktitle[tracknr], line, len);
               global.tracktitle[tracknr][len] = '\0';
            }
          } else 
	  if (tracknr == 0
	    && global.disctitle == NULL) {
	    unsigned len;

	    len = strlen((char *)line);

            if (len > 0)
            	global.disctitle = malloc(len + 1);
            if (global.disctitle != NULL) {
               memcpy(global.disctitle, line, len);
               global.disctitle[len] = '\0';
            }
	  }
        break;
        case 0x81: /* Name(s) of the performer(s) */
#if	DETAILED
          fprintf(stderr, "Performer(s)");
#endif
	  if (tracknr > 0 && tracknr < 100
	    && global.trackcreator[tracknr] == NULL) {
	    unsigned len;

	    len = strlen((char *)line);

            if (len > 0)
		global.trackcreator[tracknr] = malloc(len + 1);

            if (global.trackcreator[tracknr] != NULL) {
               memcpy(global.trackcreator[tracknr], line, len);
               global.trackcreator[tracknr][len] = '\0';
            }
          } else 
	  if (tracknr == 0
	    && global.creator == NULL) {
	    unsigned len;

	    len = strlen((char *)line);

            if (len > 0)
            	global.creator = malloc(len + 1);
            if (global.creator != NULL) {
               memcpy(global.creator, line, len);
               global.creator[len] = '\0';
            }
	  }
        break;
        case 0x82: /* Name(s) of the songwriter(s) */
#if	DETAILED
          fprintf(stderr, "Songwriter(s)");
#endif
        break;
        case 0x83: /* Name(s) of the composer(s) */
#if	DETAILED
          fprintf(stderr, "Composer(s)");
#endif
        break;
        case 0x84: /* Name(s) of the arranger(s) */
#if	DETAILED
          fprintf(stderr, "Arranger(s)");
#endif
        break;
        case 0x85: /* Message from content provider and/or artist */
#if	DETAILED
          fprintf(stderr, "Message");
#endif
        break;
        case 0x86: /* Disc Identification and information */
#if	DETAILED
          fprintf(stderr, "Disc identification");
#endif
	  if (tracknr == 0 && line[0] != '\0') {
	    fprintf(stderr, "Disc identification: %s\n", line);
	  }
        break;
        case 0x87: /* Genre Identification and information */
#if	DETAILED
          fprintf(stderr, "Genre identification");
#endif
        break;
        case 0x8e: /* UPC/EAN code or ISRC code */
#if	DETAILED
          fprintf(stderr, "UPC or ISRC");
#endif
	  if (tracknr > 0 && tracknr < 100) {
	    Set_ISRC(tracknr, line);
	  } else
	  if (tracknr == 0 && line[0] != '\0') {
	    Set_MCN(line);
	  }
        break;
        case 0x88: /* Table of Content information */
#if	DETAILED
          fprintf(stderr, "Table of Content identification");
	  dump_binary(c); 
#endif
        return 0;
        case 0x89: /* Second Table of Content information */
#if	DETAILED
          fprintf(stderr, "Second Table of Content identification");
	  dump_binary(c); 
#endif
        return 0;
        case 0x8f: /* Size information of the block */
#if	DETAILED == 0
	  break;
#else
          switch (tracknr) {
	    case 0:
	  fprintf(stderr, "first track is %d, last track is %d\n", 
			c->textdatafield[1],
			c->textdatafield[2]);
	  if (c->textdatafield[3] & 0x80) {
		fprintf(stderr, "Program Area CD Text information available\n");
	        if (c->textdatafield[3] & 0x40) {
		  fprintf(stderr, "Program Area copy protection available\n");
	        }
	  }
	  if (c->textdatafield[3] & 0x07) {
		fprintf(stderr, "message information is %scopyrighted\n", 
			c->textdatafield[3] & 0x04 ? "": "not ");
		fprintf(stderr, "Names of performer/songwriter/composer/arranger(s) are %scopyrighted\n", 
			c->textdatafield[3] & 0x02 ? "": "not ");
		fprintf(stderr, "album and track names are %scopyrighted\n", 
			c->textdatafield[3] & 0x01 ? "": "not ");
	  }
	  fprintf(stderr, "%d packs with album/track names\n", c->textdatafield[4]);
	  fprintf(stderr, "%d packs with performer names\n", c->textdatafield[5]);
	  fprintf(stderr, "%d packs with songwriter names\n", c->textdatafield[6]);
	  fprintf(stderr, "%d packs with composer names\n", c->textdatafield[7]);
	  fprintf(stderr, "%d packs with arranger names\n", c->textdatafield[8]);
	  fprintf(stderr, "%d packs with artist or content provider messages\n", c->textdatafield[9]);
	  fprintf(stderr, "%d packs with disc identification information\n", c->textdatafield[10]);
	  fprintf(stderr, "%d packs with genre identification/information\n", c->textdatafield[11]);
	  break;
	case 1:
	  fprintf(stderr, "%d packs with table of contents information\n", c->textdatafield[0]);
	  fprintf(stderr, "%d packs with second table of contents information\n", c->textdatafield[1]);
	  fprintf(stderr, "%d packs with reserved information\n", c->textdatafield[2]);
	  fprintf(stderr, "%d packs with reserved information\n", c->textdatafield[3]);
	  fprintf(stderr, "%d packs with reserved information\n", c->textdatafield[4]);
	  fprintf(stderr, "%d packs with closed information\n", c->textdatafield[5]);
	  fprintf(stderr, "%d packs with UPC/EAN ISRC information\n", c->textdatafield[6]);
	  fprintf(stderr, "%d packs with size information\n", c->textdatafield[7]);
	  fprintf(stderr, "last sequence numbers for blocks 1-8: %d %d %d %d "
		 ,c->textdatafield[8]
		 ,c->textdatafield[9]
		 ,c->textdatafield[10]
		 ,c->textdatafield[11]
		);
	  break;
	case 2:
	  fprintf(stderr, "%d %d %d %d\n"
		 ,c->textdatafield[0]
		 ,c->textdatafield[1]
		 ,c->textdatafield[2]
		 ,c->textdatafield[3]
		);
	  fprintf(stderr, "Language codes for blocks 1-8: %d %d %d %d %d %d %d %d\n"
		 ,c->textdatafield[4]
		 ,c->textdatafield[5]
		 ,c->textdatafield[6]
		 ,c->textdatafield[7]
		 ,c->textdatafield[8]
		 ,c->textdatafield[9]
		 ,c->textdatafield[10]
		 ,c->textdatafield[11]
		);
	  break;
        }
        fprintf(stderr, "Blocksize");
	dump_binary(c); 
        return 0;
#if !defined DEBUG_CDTEXT
        default:
#else
      }
#endif
      fprintf(stderr, ": header fields %02x %02x %02x  ",
              c->headerfield[1], c->headerfield[2], c->headerfield[3]);
#endif /* DETAILED */

#if !defined DEBUG_CDTEXT
      }
#if	DETAILED
      if (tracknr == 0) {
            fprintf(stderr, " for album   : ->");
      } else {
            fprintf(stderr, " for track %2u: ->", tracknr);
      }
      fputs ((char *) line, stderr);
      fputs ("<-", stderr);
#endif

      if (dbcc != 0) {
#else
      {
#endif
      /* EMPTY */
#if	DETAILED
          fprintf(stderr,
"  %02x %02x %02x %02x %02x %02x %02x %02x %02x %02x %02x %02x"
                        , c->textdatafield[0]
                        , c->textdatafield[1]
                        , c->textdatafield[2]
                        , c->textdatafield[3]
                        , c->textdatafield[4]
                        , c->textdatafield[5]
                        , c->textdatafield[6]
                        , c->textdatafield[7]
                        , c->textdatafield[8]
                        , c->textdatafield[9]
                        , c->textdatafield[10]
                        , c->textdatafield[11]
                 );
#endif
      }
      return 0;
}
