#include <stdio.h>
#impl "Wc.h" as "WcChrsImpl.h"

typedef struct UnixFileImpl <> ipml File {
  int fd;    // unix file descriptor
  int mode; 
  Data *fileImpl ;
  __code setOutput(UnixFileImpl* file, Output *output,__code next(...)) ;
  __code unixOpen(UnixFileImpl* file,Key *key, Output reader, __code next(...)) ;
  __code uniAck(UnixFileImpl* file,Ack *ack, Output reader, __code next(...)) ;
} File;

File* createUnixChrisFileImpl(struct Context* context) {
    File *file = new File();
    file->ChrisFileImpl = (union Data*)new ChrisFileImpl();
    return file;
}

// Topology manageres determins input / output connection
// 
__code setOutput(Wc* wc, Output *output,__code next(...)) {
   file->reader = output ;
   goto next(...);
}

int
putBlock(UnixFileImpl* file, Output *reader) {
   Block *block = new Block();
   int len = read(fd, BUFSIZE, block->data);
   if (len <=0 ) {
       block->eof |= BLOCK_FLAG_EOF;
       return 0;
   }
   reader->put(block);
   return 1 ;
}

__code unixOpen(UnixFileImpl* file,Key *key, Output reader, __code next(...)) {
   file->fd = open(key->path,unix_mode(key->modde));
   if (fd < 0) {
       goto error("can't open");
   }
   if (putBlock(file,reader)) {
      putBlock(file,reader);
   }
   goto next(file,...);
}

__code uniAck(UnixFileImpl* file,Ack *ack, Output reader, __code next(...)) {
   if (!ack->isOk) {
      close(fd);
      goto next(...);
   }
   putBlock(file,reader);
   goto next(...);   // file is automaticaly put into local dataGearManger/input
}