package main

import (
	"encoding/binary"
	"io"
	"log"
)

func mustWrite(w io.Writer, buf []byte) {
	if _, err := w.Write(buf); err != nil {
		log.Fatalln(err)
	}
}

func writer(w io.Writer, sink chan Ent) {
	num := make([]byte, 8)
	var name string
	for ent := range sink {
		name = ent.name[len(ent.name)-1]
		if len(ent.name) >= 1<<16 {
			panic("too long")
		}
		binary.BigEndian.PutUint16(num[:2], uint16(len(name)))
		mustWrite(w, num[:2])
		mustWrite(w, []byte(name))
		if len(ent.name) >= 1<<8 {
			panic("too deep")
		}
		mustWrite(w, []byte{byte(len(ent.name) - 1)})
		binary.BigEndian.PutUint64(num, uint64(ent.mtime))
		mustWrite(w, num)
		binary.BigEndian.PutUint64(num, uint64(ent.size))
		mustWrite(w, num)
	}
}