package core

import (
	"context"
	"time"

	"github.com/aler9/gortsplib/v2/pkg/format"
	"github.com/aler9/gortsplib/v2/pkg/media"

	"github.com/aler9/rtsp-simple-server/internal/conf"
	"github.com/aler9/rtsp-simple-server/internal/formatprocessor"
	"github.com/aler9/rtsp-simple-server/internal/logger"
	"github.com/aler9/rtsp-simple-server/internal/rpicamera"
)

func paramsFromConf(cnf *conf.PathConf) rpicamera.Params {
	return rpicamera.Params{
		CameraID:     cnf.RPICameraCamID,
		Width:        cnf.RPICameraWidth,
		Height:       cnf.RPICameraHeight,
		HFlip:        cnf.RPICameraHFlip,
		VFlip:        cnf.RPICameraVFlip,
		Brightness:   cnf.RPICameraBrightness,
		Contrast:     cnf.RPICameraContrast,
		Saturation:   cnf.RPICameraSaturation,
		Sharpness:    cnf.RPICameraSharpness,
		Exposure:     cnf.RPICameraExposure,
		AWB:          cnf.RPICameraAWB,
		Denoise:      cnf.RPICameraDenoise,
		Shutter:      cnf.RPICameraShutter,
		Metering:     cnf.RPICameraMetering,
		Gain:         cnf.RPICameraGain,
		EV:           cnf.RPICameraEV,
		ROI:          cnf.RPICameraROI,
		TuningFile:   cnf.RPICameraTuningFile,
		Mode:         cnf.RPICameraMode,
		FPS:          cnf.RPICameraFPS,
		IDRPeriod:    cnf.RPICameraIDRPeriod,
		Bitrate:      cnf.RPICameraBitrate,
		Profile:      cnf.RPICameraProfile,
		Level:        cnf.RPICameraLevel,
		AfMode:       cnf.RPICameraAfMode,
		AfRange:      cnf.RPICameraAfRange,
		AfSpeed:      cnf.RPICameraAfSpeed,
		LensPosition: cnf.RPICameraLensPosition,
		AfWindow:     cnf.RPICameraAfWindow,
	}
}

type rpiCameraSourceParent interface {
	log(logger.Level, string, ...interface{})
	sourceStaticImplSetReady(req pathSourceStaticSetReadyReq) pathSourceStaticSetReadyRes
	sourceStaticImplSetNotReady(req pathSourceStaticSetNotReadyReq)
}

type rpiCameraSource struct {
	parent rpiCameraSourceParent
}

func newRPICameraSource(
	parent rpiCameraSourceParent,
) *rpiCameraSource {
	return &rpiCameraSource{
		parent: parent,
	}
}

func (s *rpiCameraSource) Log(level logger.Level, format string, args ...interface{}) {
	s.parent.log(level, "[rpicamera source] "+format, args...)
}

// run implements sourceStaticImpl.
func (s *rpiCameraSource) run(ctx context.Context, cnf *conf.PathConf, reloadConf chan *conf.PathConf) error {
	medi := &media.Media{
		Type: media.TypeVideo,
		Formats: []format.Format{&format.H264{
			PayloadTyp:        96,
			PacketizationMode: 1,
		}},
	}
	medias := media.Medias{medi}
	var stream *stream

	onData := func(dts time.Duration, au [][]byte) {
		if stream == nil {
			res := s.parent.sourceStaticImplSetReady(pathSourceStaticSetReadyReq{
				medias:             medias,
				generateRTPPackets: true,
			})
			if res.err != nil {
				return
			}

			s.Log(logger.Info, "ready: %s", sourceMediaInfo(medias))
			stream = res.stream
		}

		err := stream.writeData(medi, medi.Formats[0], &formatprocessor.UnitH264{
			PTS: dts,
			AU:  au,
			NTP: time.Now(),
		})
		if err != nil {
			s.Log(logger.Warn, "%v", err)
		}
	}

	cam, err := rpicamera.New(paramsFromConf(cnf), onData)
	if err != nil {
		return err
	}
	defer cam.Close()

	defer func() {
		if stream != nil {
			s.parent.sourceStaticImplSetNotReady(pathSourceStaticSetNotReadyReq{})
		}
	}()

	for {
		select {
		case cnf := <-reloadConf:
			cam.ReloadParams(paramsFromConf(cnf))

		case <-ctx.Done():
			return nil
		}
	}
}

// apiSourceDescribe implements sourceStaticImpl.
func (*rpiCameraSource) apiSourceDescribe() interface{} {
	return struct {
		Type string `json:"type"`
	}{"rpiCameraSource"}
}