package roaring

import (
	"encoding/binary"
	"io"
)

// writeTo for runContainer16 follows this
// spec: https://github.com/RoaringBitmap/RoaringFormatSpec
//
func (b *runContainer16) writeTo(stream io.Writer) (int, error) {
	buf := make([]byte, 2+4*len(b.iv))
	binary.LittleEndian.PutUint16(buf[0:], uint16(len(b.iv)))
	for i, v := range b.iv {
		binary.LittleEndian.PutUint16(buf[2+i*4:], v.start)
		binary.LittleEndian.PutUint16(buf[2+2+i*4:], v.length)
	}
	return stream.Write(buf)
}