package httpflv

import (
	"bufio"
	"errors"
	"strings"
)

type Writer interface {
	// TODO chef: return error
	WriteTag(tag *Tag)
}

var httpFlvErr = errors.New("httpflv: fxxk")

var readBufSize = 16384

// return 1st line and other headers with kv format
func parseHTTPHeader(r *bufio.Reader) (n int, firstLine string, headers map[string]string, err error) {
	headers = make(map[string]string)

	var line []byte
	var isPrefix bool
	line, isPrefix, err = r.ReadLine()
	if err != nil {
		return
	}
	if len(line) == 0 || isPrefix {
		err = httpFlvErr
		return
	}
	firstLine = string(line)
	n += len(line)

	for {
		line, isPrefix, err = r.ReadLine()
		if len(line) == 0 { // 读到一个空的 \r\n 表示http头全部读取完毕了
			break
		}
		if isPrefix {
			err = httpFlvErr
			return
		}
		if err != nil {
			return
		}
		l := string(line)
		n += len(l)
		pos := strings.Index(l, ":")
		if pos == -1 {
			err = httpFlvErr
			return
		}
		headers[strings.Trim(l[0:pos], " ")] = strings.Trim(l[pos+1:], " ")
	}
	return
}