package utils

import (
	"go.uber.org/zap"
	"regexp"
	"strings"

	rotatelogs "github.com/lestrrat-go/file-rotatelogs"
)

const (
	EndTag         = "NNNN"
	Expression     = "(?s)ZCZC.*?NNNN"
	MaxBufferSize  = 65536
	BufferTrimSize = 32768
)

var buffer string
var exp, _ = regexp.Compile(Expression)
var RawLog *rotatelogs.RotateLogs
var Tcp bool
var Pulsar bool

func Append(data string) bool {
	buffer += data + "\n"
	if len(buffer) > MaxBufferSize {
		Log.Warn("buffer overflow, truncating",
			zap.Int("size", len(buffer)),
			zap.Int("max", MaxBufferSize))
		buffer = buffer[len(buffer)-BufferTrimSize:]
	}
	return check()
}

func check() bool {
	teleString := buffer
	if strings.Contains(teleString, EndTag) {
		loc := exp.FindStringIndex(teleString)
		if loc != nil {
			telegram := teleString[loc[0]:loc[1]]
			telegram = removeEmpty(telegram) + "\n\n"
			telegram += "\n"
			_, _ = RawLog.Write([]byte(telegram + "\n"))
			buffer = teleString[loc[1]:]

			// 先持久化，再发送：即使发送失败，数据已安全落盘
			if err := InsertTelegram(telegram); err != nil {
				Log.Error("error in save telegram to db", zap.Error(err))
			}
			if Pulsar {
				if err := PulsarSend(telegram); err != nil {
					Log.Error("error in send to pulsar", zap.Error(err))
				}
			}
			return true
		}
	}
	return false
}

func removeEmpty(s string) string {
	return regexp.MustCompile(`[\t\r\n]+`).ReplaceAllString(strings.TrimSpace(s), "\n")
}