package producer

import (
	"errors"
	"image"

	"github.com/duke-git/lancet/v2/slice"
	log "github.com/sirupsen/logrus"
	"gocv.io/x/gocv"
)

type PhaseShiftM struct {
	dx       float32
	dy       float32
	response float64
	Block    Block
}

type Block struct {
	width  int
	height int
	coord  image.Point // top-left corner of the block in the original image
}

func (r *ImgProc) calculateBlockPhaseShift(panBlock, mssBlock gocv.Mat) (gocv.Point2f, float64) {
	pan := gocv.NewMat()
	mss := gocv.NewMat()

	panBlock.ConvertTo(&pan, gocv.MatTypeCV32FC1)
	defer pan.Close()
	mssBlock.ConvertTo(&mss, gocv.MatTypeCV32FC1)
	defer mss.Close()

	hann := gocv.NewMat()
	defer hann.Close()

	shift, response := gocv.PhaseCorrelate(pan, mss, hann)

	dx := shift.X
	dy := shift.Y
	log.Debugf("Block shift: dx = %f, dy = %f. response = %f", dx, dy, response)

	return shift, response
}

func (r *ImgProc) fileterPhaseShift(thredholds []float64, greaterThan bool) error {
	if len(thredholds) > 4 {
		return errors.New("thredholds length should be less than 4")
	}

	for i := 0; i < len(thredholds); i++ {
		th := thredholds[i]
		r.phaseShifts[i] = slice.Filter(r.phaseShifts[i], func(i int, value PhaseShiftM) bool {
			if value.response > 0.999999 {
				return false
			}

			if greaterThan {
				return value.dy > float32(th)
			}
			return value.dy < float32(th)
		})
	}

	return nil
}