#include <stdio.h>
#include <string.h>

double LENGTH;
char TITLE[256], EMU[256];
unsigned RECORDS;
double FPS = 60;

static void ReadFMV(FILE *fp)
{
    unsigned char Header[144];
    unsigned FLAGS;
    unsigned bytes_per_frame = 0;

    rewind(fp);
    fread(Header,1,sizeof Header, fp);

    if(memcmp(Header+0, "FMV", 3) != 0) return;
    
    sprintf(TITLE, "%.63s", Header+80);
    sprintf(EMU,   "%.63s", Header+16);
    
    RECORDS = Header[10]
             +Header[11]*256;
       //    +Header[12]*256*256
       //    +Header[13]*256*256*256;
    FLAGS   = Header[5];
    
    // FLAGS & 0x80 = player 1
    // FLAGS & 0x40 = player 2
    // FLAGS & 0x20 = FDS
    
    if(FLAGS & 0x20) ++bytes_per_frame;
    if(FLAGS & 0x40) ++bytes_per_frame;
    if(FLAGS & 0x80) ++bytes_per_frame;
    
    ++RECORDS; // Famtasia does this too
    
    fseek(fp,0,SEEK_END);
    LENGTH = (ftell(fp) - sizeof(Header)) / (bytes_per_frame * 60.0);
}

static void ReadGMV(FILE *fp)
{
    unsigned char Header[64];
    unsigned bytes_per_frame = 3;

    rewind(fp);
    fread(Header,1,sizeof Header, fp);

    if(memcmp(Header+0, "Gens", 4) != 0) return;
    
    sprintf(TITLE, "%.39s", Header+24);
    
    RECORDS = Header[16]
             +Header[17]*256
             +Header[18]*256*256
             +Header[19]*256*256*256;

    fseek(fp,0,SEEK_END);
    LENGTH = (ftell(fp) - sizeof(Header)) / (bytes_per_frame * 60.0);
}

static void ReadSMV(FILE *fp)
{
    unsigned char Header[32];
    unsigned OFS_STATE;
    unsigned metalen, a;

    rewind(fp);
    fread(Header,1,sizeof Header, fp);

    if(memcmp(Header+0, "SMV\32", 4) != 0) return;
    
    FPS = (Header[0x15] & 2) ? 50 : 60;
    
    RECORDS = Header[12]
             +Header[13]*256
             +Header[14]*256*256
             +Header[15]*256*256*256;
    LENGTH  = Header[16]
             +Header[17]*256
             +Header[18]*256*256
             +Header[19]*256*256*256;
    
    OFS_STATE=Header[24]
             +Header[25]*256
             +Header[26]*256*256
             +Header[27]*256*256*256;

    LENGTH = LENGTH / FPS;
    
    metalen = OFS_STATE - sizeof(Header);
    for(a=0; a<metalen && a < (sizeof TITLE - 1); ++a)
    {
        int c = fgetc(fp);
        c |= fgetc(fp) << 8;
        TITLE[a] = (char)c;
    }
    TITLE[a] = 0;
}

static void ReadVBM(FILE *fp)
{
    unsigned char Header[64+192];
    unsigned metalen, a;

    rewind(fp);
    fread(Header,1,sizeof Header, fp);

    if(memcmp(Header+0, "VBM\32", 4) != 0) return;
    
    FPS = 60;
    
    RECORDS = Header[16]
             +Header[17]*256
             +Header[18]*256*256
             +Header[19]*256*256*256;
    LENGTH  = Header[12]
             +Header[13]*256
             +Header[14]*256*256
             +Header[15]*256*256*256;
    
    sprintf(TITLE, "%.64s;%.128s", Header+64, Header+64+64);

    LENGTH = LENGTH / FPS;
}

static void ReadM64(FILE *fp)
{
    unsigned char Header[1024];
    unsigned metalen, a;

    rewind(fp);
    fread(Header,1,sizeof Header, fp);

    if(memcmp(Header+0, "M64\32", 4) != 0) return;
    
    FPS = Header[0x14];
    
    RECORDS = Header[16]
             +Header[17]*256
             +Header[18]*256*256
             +Header[19]*256*256*256;
    LENGTH  = Header[12]
             +Header[13]*256
             +Header[14]*256*256
             +Header[15]*256*256*256;
    
    sprintf(TITLE, "%.64s;%.128s", Header+222, Header+300);

    LENGTH = LENGTH / FPS;
}
static void ReadFCM(FILE *fp)
{
    unsigned char Header[4096];
    unsigned metapos, metalen, a;

    rewind(fp);
    fread(Header,1,sizeof Header, fp);

    if(memcmp(Header+0, "FCM\32", 4) != 0) return;
    
    FPS = (Header[0x08] & 4) ? 50 : 60;
    
    RECORDS = Header[16]
             +Header[17]*256
             +Header[18]*256*256
             +Header[19]*256*256*256;
    LENGTH  = Header[12]
             +Header[13]*256
             +Header[14]*256*256
             +Header[15]*256*256*256;
    
    LENGTH = LENGTH / FPS;
    
    for(metapos=0x34; Header[metapos] != '\0'; ++metapos);
    ++metapos;
    
    for(a=0; Header[metapos] != '\0' && a < (sizeof TITLE - 1); ++a)
    {
        int c = Header[metapos++];
        TITLE[a] = (char)c;
    }
    TITLE[a] = 0;
}

static void ReadMovie(FILE *fp)
{
    ReadFMV(fp);
    ReadGMV(fp);
    ReadSMV(fp);
    ReadFCM(fp);
    ReadM64(fp);
    ReadVBM(fp);
}

int main(int argc, const char*const *argv)
{
    long tmp;
    FILE*fp = fopen(argv[1], "rb");
    if(!fp) { perror(argv[1]); return -1; }

    ReadMovie(fp);
    
    fclose(fp);
    fp = fopen("test0.sub", "wt");
    
    tmp = (long)LENGTH;
    
    fprintf(fp, "{%.0f}{%.0f}%s|Play length %ld:%02ld:%05.2f|Rerecord count: %u\n", 
        FPS * 1.0, FPS * 3.0,

        TITLE,
        
        tmp / 3600,
        (tmp / 60) % 60,
        tmp % 60 + (LENGTH - tmp),
        
        RECORDS+1
           );
    fprintf(fp, "{%.0f}{%.0f}This is a tool-assisted recording, played on an emulator.|For details, see http://TASvideos.org/\n",
        FPS * 3.2,
        FPS * 5.2,
        EMU);
    
    return 0;
}