#include <stdio.h>
#include <unistd.h>
#include <string.h>
#include <errno.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#include "cdreader.h"
#include "Exceptions.h"
#include "generic.h"
#ifdef HAVE_CONFIG_H
#include "config.h"
#else
#define _(x) x
#endif

#ifdef __linux__
#include <sys/ioctl.h>
#include <linux/cdrom.h>

cdreader::cdreader(const String & no) throw (GeneralException) :
    Handle(open(no.to_charp(), O_RDONLY)), n(no), sector(0) {

#ifdef DEBUG    
    fprintf(stderr, "Opening file %s, cdreader at %p\n", no.to_charp(), this);
#endif

    if (GetHandle() < 0) {
	throw IOGeneral(String(_("Error opening file ")) + no + _(" for reading: ") + strerror(errno));
    }
    
    struct stat s;
    fstat(GetHandle(), &s);

    if (!S_ISBLK(s.st_mode)) {
	throw GeneralException(no + " is not a block device.");
    }
}

cdreader::cdreader(const cdreader & i) : Handle(i), n(i.n) {
}

bool cdreader::CanWrite() {
    return 0;
}

bool cdreader::CanRead() {
    return 1;
}

bool cdreader::CanSeek() {
    return 1;
}

String cdreader::GetName() {
    return n + " raw reading";
}

ssize_t cdreader::GetSize() {
    return -1;
}

off_t cdreader::seek(off_t offset, int whence) throw (GeneralException) {
    switch (whence) {
    case SEEK_SET:
	itell = offset;
	break;
    case SEEK_CUR:
	itell += offset;
	break;
    case SEEK_END:
	throw GeneralException("Can not yet seek from the end of a CD.");
    }
    return itell;
}

ssize_t cdreader::read(void *buf, size_t count) throw (GeneralException) {
    char sector[CD_FRAMESIZE_RAW];
    size_t r = count;
    
    size_t remain = itell % CD_FRAMESIZE_RAW;
    sectorseek(itell / CD_FRAMESIZE_RAW);
    
    while (count > 0) {
	size_t n = CD_FRAMESIZE_RAW - remain;
	getsector(sector);
	bcopy(sector, ((char *) buf) + remain, MIN(n, count));
	count -= n;
	remain = 0;
    }
    
    return r;
}

void cdreader::getsector(void *buf, int sec) throw (GeneralException) {
    struct cdrom_msf * msf = (struct cdrom_msf *) buf;
    if (sec >= 0)
	sector = sec;
    
    fprintf(stderr, "Reading sector %i\n", sector);

    sector += 150;
    
    msf->cdmsf_min0  =   sector   /CD_SECS   /CD_FRAMES;
    msf->cdmsf_sec0  =  (sector   /CD_FRAMES)%CD_SECS;
    msf->cdmsf_frame0=   sector   %CD_FRAMES;
    msf->cdmsf_min1  =  (sector+1)/CD_SECS   /CD_FRAMES;
    msf->cdmsf_sec1  = ((sector+1)/CD_FRAMES)%CD_SECS;
    msf->cdmsf_frame1=  (sector+1)%CD_FRAMES;
    
    sector -= 150;

    if (ioctl(GetHandle(), CDROMREADRAW, buf) < 0) {
	throw GeneralException(String("unable to read cd sector ") + sector + ": " + strerror(errno));
    }
    
    sector++;
}

void cdreader::sectorseek(int sec) {
    sector = sec;
}

#endif