/*
 * uncompress.c  V0.7.01
 *
 * uncompress and load a data file
 *
 * (c) 1992-93 Stefan Becker
 *
 */

#include "uuxqt.h"

static const char ReadErrMsg[]="read error on file '%s'!\n";

/* Uncompress data file into temporary file */
static char *UncompressFile(char *name, char *command, ULONG offset)
{
 char *rc=NULL;
 BPTR infile;

 /* Open AmigaDOS file */
 if (infile=Open(name,MODE_OLDFILE)) {

  /* Seek into file */
  Seek(infile,offset,OFFSET_BEGINNING);

  /* No error? */
  if (IoErr()==0) {
   char *outname=tmpnam(NULL);

   /* Create command string */
   sprintf(Tmp1Buffer,"%s -d >%s",command,outname);

   /* Run command */
   if (SystemTags(Tmp1Buffer,SYS_Input,     infile,
                             SYS_UserShell, TRUE,
                             TAG_DONE)==0)
    /* News file decompressed */
    rc=outname;
   else
    ErrLog("error in '%s' command!\n",Tmp1Buffer);

  } else
   ErrLog("seek error in compressed file '%s'!\n",name);

  Close(infile);
 } else
  ErrLog("couldn't open compressed file '%s'!\n",name);

 return(rc);
}

char *GetDataFile(char *datafile, ULONG *size)
{
 FILE *fh;

 /* Open date file */
 if (fh=fopen(datafile,"r")) {
  int c;

  /* Read first character */
  if ((c=fgetc(fh))!=EOF) {
   char *tmpfilename=NULL;
   BOOL dodelete=TRUE;

   /* Detect file type */
   {
    int offset=0;

    /* Command line? */
    if (c=='#') {
     /* Yes, skip complete command line */
     offset=2;
     while (((c=fgetc(fh))!='\n') && (c!=EOF)) offset++;
     c=fgetc(fh);
    }

    /* Compressed file? */
    if (c=='\x1f') {

     /* Yes, check compression type */
     if ((c=fgetc(fh))!=EOF)
      switch (c) {
       case '\x8b': /* Zipped */
                    tmpfilename=UncompressFile(datafile,"gzip",offset);
                    break;
       case '\x9d': /* Compressed */
                    tmpfilename=UncompressFile(datafile,"compress",offset);
                    break;
       case '\x9f': /* Frozen */
                    tmpfilename=UncompressFile(datafile,"freeze",offset);
                    break;
       default:     ErrLog("Unknown compression type in file '%s'!\n",datafile);
                    break;
      }
     else
      ErrLog(ReadErrMsg,datafile);

    /* Uncompressed file? */
    } else if (c!=EOF) {
     tmpfilename=datafile;
     dodelete=FALSE;

    /* File error */
    } else
     ErrLog(ReadErrMsg,datafile);
   }

   /* Temporary file name set? */
   if (tmpfilename) {
    ULONG filesize=0;

    /* Get file size */
    {
     struct stat statbuf;

     /* Get file statistic */
     if (stat(tmpfilename,&statbuf)!=-1)
      filesize=statbuf.st_size;
     else
      ErrLog("couldn't stat data file '%s'!\n",tmpfilename);
    }

    /* File size set? */
    if (filesize) {
     char *buffer;

     /* Can the buffer be allocated? */
     if (buffer=AllocVec(filesize+1,MEMF_PUBLIC)) {
      BPTR infile;

      /* Open temporary file */
      if (infile=Open(tmpfilename,MODE_OLDFILE)) {

       /* Read data file into buffer */
       if (Read(infile,buffer,filesize)==filesize) {
        /* Data file read in. Close and delete it */
        Close(infile);
        fclose(fh);
        if (dodelete) DeleteFile(tmpfilename);

        /* Set string terminator */
        buffer[filesize]='\0';

        /* Return parameters */
        *size=filesize;
        return(buffer);
       }
       Close(infile);
      }
      FreeVec(buffer);
     } else
      ErrLog("couldn't allocate buffer for data file '%s'!\n",tmpfilename);

    }
    if (dodelete) DeleteFile(tmpfilename);
   }
  } else
   ErrLog(ReadErrMsg,datafile);

  fclose(fh);
 } else
  ErrLog("couldn't open data file '%s'!\n",datafile);

 return(NULL);
}