package hdl

import (
	"bufio"
	"io"
	"net/http"
	"os"
	"strings"

	. "github.com/Monibuca/engine/v4"
	"github.com/Monibuca/engine/v4/codec"
	"github.com/Monibuca/engine/v4/log"
	"github.com/Monibuca/engine/v4/util"
	"go.uber.org/zap"
)

func (puller *HDLPuller) connect() (err error) {
	puller.ReConnectCount++
	log.Info("connect", zap.String("remoteURL", puller.RemoteURL))
	if strings.HasPrefix(puller.RemoteURL, "http") {
		var res *http.Response
		if res, err = http.Get(puller.RemoteURL); err == nil {
			puller.OnEvent(res.Body)
		}
	} else {
		var res *os.File
		if res, err = os.Open(puller.RemoteURL); err == nil {
			puller.OnEvent(res)
		}
	}
	if err != nil {
		log.Error("connect", zap.Error(err))
	}
	return
}
func (puller *HDLPuller) pull() {
	var err error
	defer func() {
		puller.Closer.Close()
		if !puller.Stream.IsClosed() {
			if err = puller.connect(); err == nil {
				go puller.pull()
			}
		} else {
			puller.Info("stop", zap.String("remoteURL", puller.RemoteURL))
		}
	}()
	head := util.Buffer(make([]byte, len(codec.FLVHeader)))
	reader := bufio.NewReader(puller)
	_, err = io.ReadFull(reader, head)
	if err != nil {
		return
	}
	head.Reset()
	var startTs uint32
	for offsetTs := puller.absTS; err == nil && puller.Err() == nil; _, err = io.ReadFull(reader, head[:4]) {
		tmp := head.SubBuf(0, 11)
		_, err = io.ReadFull(reader, tmp)
		if err != nil {
			return
		}
		t := tmp.ReadByte()
		dataSize := tmp.ReadUint24()
		timestamp := tmp.ReadUint24() | uint32(tmp.ReadByte())<<24
		if startTs == 0 {
			startTs = timestamp
		}
		tmp.ReadUint24()
		payload := make([]byte, dataSize)
		_, err = io.ReadFull(reader, payload)
		if err != nil {
			return
		}
		puller.absTS = offsetTs + (timestamp - startTs)
		switch t {
		case codec.FLV_TAG_TYPE_AUDIO:
			puller.AudioTrack.WriteAVCC(puller.absTS, payload)
		case codec.FLV_TAG_TYPE_VIDEO:
			puller.VideoTrack.WriteAVCC(puller.absTS, payload)
		}
	}
}

type HDLPuller struct {
	Publisher
	Puller
	absTS uint32 //绝对时间戳
}

func (puller *HDLPuller) OnEvent(event any) {
	switch event.(type) {
	case SEpublish:
		go puller.pull() //阻塞拉流
	default:
		puller.Publisher.OnEvent(event)
	}
}