// +build !circleci

/*
DESCRIPTION
  A filter that detects motion and discards frames without motion. The
  filter uses a Mixture of Gaussians method (MoG) to determine what is
  background and what is foreground.

AUTHORS
  Scott Barnard <scott@ausocean.org>

LICENSE
  mog.go is Copyright (C) 2019 the Australian Ocean Lab (AusOcean)

  It is free software: you can redistribute it and/or modify them
  under the terms of the GNU General Public License as published by the
  Free Software Foundation, either version 3 of the License, or (at your
  option) any later version.

  It is distributed in the hope that it will be useful, but WITHOUT
  ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
  for more details.

  You should have received a copy of the GNU General Public License
  in gpl.txt.  If not, see http://www.gnu.org/licenses.
*/

package filter

import (
	"io"
)

// MOGFilter is a filter that provides basic motion detection. MoG is short for
// Mixture of Gaussians method.
type BasicFilter struct {
	dst io.WriteCloser
}

// NewMOGFilter returns a pointer to a new MOGFilter struct.
func NewBasicFilter(dst io.WriteCloser) *BasicFilter {
	return &BasicFilter{dst}
}

// Implements io.Closer.
// Close frees resources used by gocv, because it has to be done manually, due to
// it using c-go.
func (m *BasicFilter) Close() error {
	return nil
}

// Implements io.Writer.
// Write applies the motion filter to the video stream. Only frames with motion
// are written to the destination encoder, frames without are discarded.
func (m *BasicFilter) Write(f []byte) (int, error) {
	//decode MJPEG

	//for all frames find difference in this frame from last frames

	return m.dst.Write(f)
}