public static Gst.Caps NewEmpty () {
  return new Gst.Caps ();
}

public Caps (Structure s) : this () {
  Append (s);
}

public Caps (Structure[] s) : this () {
  foreach (Structure o in s)
    Append (o);
}

[DllImport ("gstreamersharpglue-0.10") ]
extern static uint gstsharp_gst_caps_get_refcount_offset ();

static uint refcount_offset = gstsharp_gst_caps_get_refcount_offset ();
private int Refcount {
  get {
    unsafe {
      int* raw_ptr = (int*) ( ( (byte*) Handle) + refcount_offset);
      return (*raw_ptr);
    }
  }
}

public bool IsWritable {
  get {
    return (Refcount == 1);
  }
}

/* FIXME: This is not optimal! */
public void MakeWritable() {
  if (IsWritable)
    return;

  IntPtr copy = gst_caps_copy (Raw);
  Raw = copy;
  /* ^--- Takes a second ref, not good */
  Unref (Raw);
  /* ^--- Sets Owned = false, wrong! */
  Owned = true;
}

[DllImport ("gstreamer-0.10.dll") ]
private static extern IntPtr gst_caps_get_structure (IntPtr handle, uint index);

public Structure this [uint index] {
  get {
    if (index >= Size)
      throw new ArgumentOutOfRangeException ();

    IntPtr raw_ptr = gst_caps_get_structure (Handle, (uint) index);

    return (Gst.Structure) new Gst.Structure (raw_ptr);
  }
}

private class StructureEnumerator : IEnumerator {
  Gst.Caps caps;
  long index;

  public StructureEnumerator (Gst.Caps caps) {
    this.caps = caps;
    index = -1;
  }

  public object Current {
    get {
      if (index >= caps.Size)
        throw new ArgumentOutOfRangeException ();
      if (index == -1)
        throw new ArgumentException ();

      return caps[ (uint) index];
    }
  }

  public bool MoveNext () {
    index += 1;
    return (index < caps.Size);
  }

  public void Reset () {
    index = -1;
  }
}

public IEnumerator GetEnumerator() {
  return new StructureEnumerator (this);
}

[DllImport ("gstreamer-0.10.dll") ]
static extern void gst_caps_append_structure (IntPtr caps, IntPtr structure);

public void Append (Structure s) {
  if (!IsWritable)
    throw new ApplicationException ();

  gst_caps_append_structure (Handle, s.Copy().Handle);
}

[DllImport ("gstreamer-0.10.dll") ]
static extern void gst_caps_append (IntPtr caps, IntPtr caps2);

public void Append (Caps caps) {
  if (!IsWritable)
    throw new ApplicationException ();

  gst_caps_append (Handle, caps.Copy().Handle);
}

[DllImport ("gstreamer-0.10.dll") ]
static extern void gst_caps_merge_structure (IntPtr caps, IntPtr structure);

public void Merge (Structure s) {
  if (!IsWritable)
    throw new ApplicationException ();

  gst_caps_merge_structure (Handle, s.Copy().Handle);
}

[DllImport ("gstreamer-0.10.dll") ]
static extern void gst_caps_merge (IntPtr caps, IntPtr caps2);

public void Merge (Caps caps) {
  if (!IsWritable)
    throw new ApplicationException ();

  gst_caps_merge (Handle, caps.Copy().Handle);
}

[DllImport ("gstreamer-0.10.dll") ]
static extern void gst_caps_remove_structure (IntPtr caps, uint index);

public void RemoveStructure (uint index) {
  if (!IsWritable)
    throw new ApplicationException ();
  if (index >= Size)
    throw new ArgumentOutOfRangeException ();

  gst_caps_remove_structure (Handle, index);
}

[DllImport ("gstreamer-0.10.dll") ]
static extern bool gst_caps_do_simplify (IntPtr caps);

public bool DoSimplify () {
  if (!IsWritable)
    throw new ApplicationException ();

  return gst_caps_do_simplify (Handle);
}

[DllImport ("gstreamer-0.10.dll") ]
static extern void gst_caps_truncate (IntPtr caps);

public void Truncate () {
  if (!IsWritable)
    throw new ApplicationException ();

  gst_caps_truncate (Handle);
}