/*

  * cws2fws by Alex Beregszaszi

  * This file is placed in the public domain.
  * Use the program however you see fit.

  *
  * This utility converts compressed Macromedia Flash files to uncompressed ones.
  */
 

 #include "config.h"

 #include <sys/stat.h>
 #include <fcntl.h>

 #include <stdio.h>
 #include <stdlib.h>

 #if HAVE_UNISTD_H

 #include <unistd.h>

 #endif
 #if HAVE_IO_H
 #include <io.h>
 #endif

 #include <zlib.h>
 
 #ifdef DEBUG
 #define dbgprintf printf
 #else

 #define dbgprintf(...)

 #endif
 

 int main(int argc, char *argv[])

 {

     int fd_in, fd_out, comp_len, uncomp_len, i, last_out;

     char buf_in[1024], buf_out[65536];

     z_stream zstream;
     struct stat statbuf;
 

     if (argc < 3) {

         printf("Usage: %s <infile.swf> <outfile.swf>\n", argv[0]);

         return 1;

     }

     fd_in = open(argv[1], O_RDONLY);

     if (fd_in < 0) {

         perror("Error opening input file");

         return 1;

     }
 

     fd_out = open(argv[2], O_WRONLY | O_CREAT, 00644);
     if (fd_out < 0) {

         perror("Error opening output file");

         close(fd_in);

         return 1;

     }

     if (read(fd_in, &buf_in, 8) != 8) {

         printf("Header error\n");
         close(fd_in);
         close(fd_out);

         return 1;

     }

     if (buf_in[0] != 'C' || buf_in[1] != 'W' || buf_in[2] != 'S') {

         printf("Not a compressed flash file\n");

         return 1;

     }
 

     if (fstat(fd_in, &statbuf) < 0) {
         perror("fstat failed");
         return 1;
     }

     comp_len   = statbuf.st_size;

     uncomp_len = buf_in[4] | (buf_in[5] << 8) | (buf_in[6] << 16) | (buf_in[7] << 24);

     printf("Compressed size: %d Uncompressed size: %d\n",
            comp_len - 4, uncomp_len - 4);

 
     // write out modified header
     buf_in[0] = 'F';

     if (write(fd_out, &buf_in, 8) < 8) {
         perror("Error writing output file");

         return 1;

     }

 
     zstream.zalloc = NULL;

     zstream.zfree  = NULL;

     zstream.opaque = NULL;

     if (inflateInit(&zstream) != Z_OK) {
         fprintf(stderr, "inflateInit failed\n");
         return 1;
     }

     for (i = 0; i < comp_len - 8;) {

         int ret, len = read(fd_in, &buf_in, 1024);

         dbgprintf("read %d bytes\n", len);

         last_out = zstream.total_out;

         zstream.next_in   = &buf_in[0];
         zstream.avail_in  = len;
         zstream.next_out  = &buf_out[0];

         zstream.avail_out = 65536;

         ret = inflate(&zstream, Z_SYNC_FLUSH);

         if (ret != Z_STREAM_END && ret != Z_OK) {

             printf("Error while decompressing: %d\n", ret);
             inflateEnd(&zstream);

             return 1;

         }

         dbgprintf("a_in: %d t_in: %lu a_out: %d t_out: %lu -- %lu out\n",

                   zstream.avail_in, zstream.total_in, zstream.avail_out,
                   zstream.total_out, zstream.total_out - last_out);

         if (write(fd_out, &buf_out, zstream.total_out - last_out) <
             zstream.total_out - last_out) {

             perror("Error writing output file");

             return 1;

         }

         i += len;

 
         if (ret == Z_STREAM_END || ret == Z_BUF_ERROR)
             break;

     }

     if (zstream.total_out != uncomp_len - 8) {

         printf("Size mismatch (%lu != %d), updating header...\n",

                zstream.total_out, uncomp_len - 8);

         buf_in[0] =  (zstream.total_out + 8)        & 0xff;
         buf_in[1] = ((zstream.total_out + 8) >>  8) & 0xff;
         buf_in[2] = ((zstream.total_out + 8) >> 16) & 0xff;
         buf_in[3] = ((zstream.total_out + 8) >> 24) & 0xff;

         if (   lseek(fd_out, 4, SEEK_SET) < 0
             || write(fd_out, &buf_in, 4) < 4) {

             perror("Error writing output file");

             return 1;

         }

     }

     inflateEnd(&zstream);
     close(fd_in);
     close(fd_out);

     return 0;

 }