package storage

import "encoding/binary"

type revision struct {
	main int64
	sub  int64
}

func (a revision) GreaterThan(b revision) bool {
	if a.main > b.main {
		return true
	}
	if a.main < b.main {
		return false
	}
	return a.sub > b.sub
}

func newRevBytes() []byte {
	return make([]byte, 8+1+8)
}

func revToBytes(rev revision, bytes []byte) {
	binary.BigEndian.PutUint64(bytes, uint64(rev.main))
	bytes[8] = '_'
	binary.BigEndian.PutUint64(bytes[9:], uint64(rev.sub))
}

func bytesToRev(bytes []byte) revision {
	return revision{
		main: int64(binary.BigEndian.Uint64(bytes[0:8])),
		sub:  int64(binary.BigEndian.Uint64(bytes[9:])),
	}
}