use v6;

use NativeCall;

constant GDBM_BLOCKSIZE = 0;
constant GDBM_WRCREAT   = 2;

constant GDBM_REPLACE = 1;

class datum is repr('CStruct') {
  has Str $.dptr is rw;
  has int32 $.dsize is rw;
}

class DBM::GDBM is repr('CPointer') {

    sub gdbm_open(
      Str           $name,
      int32         $block_size,
      int32         $flags,
      int32         $mode,
      Pointer[void] $fatal_func
    )
      returns DBM::GDBM is native('libgdbm.so.3') { * }

    sub gdbm_store(
      DBM::GDBM $dbf,
      datum     $key,
      datum     $content,
      int32     $flag,
    )
      returns int32 is native('libgdbm.so.3') { * }

    method new($gdbm_file_name, $flags, $mode) {
      return gdbm_open($gdbm_file_name, GDBM_BLOCKSIZE, GDBM_WRCREAT, $mode, Nil);
    }

    method store(Str $key is rw, Str $value is rw) {
      my datum $key_datum     = datum.new(dptr => $key, dsize => $key.chars);
      my datum $content_datum = datum.new(dptr => $value, dsize => $value.chars);

      return gdbm_store(self, $key_datum, $content_datum, GDBM_REPLACE);
    }
}