package capture

import (
	"errors"
	"fmt"
	"image"
	"time"

	"basic.com/valib/goffmpeg.git"
	"gocv.io/x/gocv"
)

// StreamMode stream mode
type StreamMode int

const (
	// Rtsp mode
	Rtsp = StreamMode(iota)
	// GB28181 mode
	GB28181
)

// PicExt file extention
type PicExt string

const (
	// PNGFileExt png
	PNGFileExt PicExt = PicExt(gocv.PNGFileExt)
	// JPEGFileExt jpeg
	JPEGFileExt PicExt = PicExt(gocv.JPEGFileExt)
	// GIFFileExt gif
	GIFFileExt PicExt = PicExt(gocv.GIFFileExt)
	// InvalidFileExt invalid
	InvalidFileExt PicExt = PicExt("")
)

// Capture pic
func Capture(soFile string, m StreamMode, url string, ext PicExt, w, h, maxTry int) ([]byte, error) {
	gb := false
	if m == GB28181 {
		gb = true
	} else if m != Rtsp {
		return nil, errors.New("there is no this mode, try capture.Rtsp/capture.GB28181")
	}

	if ext == InvalidFileExt {
		ext = JPEGFileExt
	}
	var ret []byte
	var err error

	err = goffmpeg.InitFFmpeg(soFile)
	if err != nil {
		return nil, err
	}

	conf := goffmpeg.Config{
		Scale:  goffmpeg.ScalePoint,
		Width:  w,
		Height: h,
		GB:     gb,
		CPU:    true,
	}
	gf := goffmpeg.New(conf)

	ret, err = capt2Data(gf, url, gocv.FileExt(ext), w, h, maxTry)

	gf.Free()
	goffmpeg.FreeFFmpeg()

	return ret, err
}

func capt2Data(gf *goffmpeg.GoFFMPEG, url string, ext gocv.FileExt, w, h, maxTry int) ([]byte, error) {

	gf.Run(url)
	gf.BuildDecoder()

	tryTime := 0

	var picData []byte
	var err2 error
	for {

		data, wid, hei, _ := gf.GetPicDecoder()
		if wid > 0 && hei > 0 {
			img, err := gocv.NewMatFromBytes(hei, wid, gocv.MatTypeCV8UC3, data)
			if err != nil {
				continue
			}
			pic := img
			if w >= 0 && h >= 0 {
				pic = gocv.NewMatWithSize(h, w, gocv.MatTypeCV8UC3)
				gocv.Resize(img, &pic, image.Pt(w, h), 0, 0, gocv.InterpolationDefault)
			}
			picData, err2 = gocv.IMEncode(ext, pic)
			if err2 != nil {
				continue
			}
			break
		} else {
			tryTime++
			if tryTime > maxTry {
				break
			}
			time.Sleep(time.Second)
		}
	}

	if tryTime > maxTry {
		err := fmt.Sprintf("try %d times to capture image, is url correct?\n", tryTime)
		return nil, errors.New(err)
	}

	return picData, nil
}