package logging

import (
	"unicode/utf8"
)

// Close conforms a nullWriter to an io.WriteCloser. It obviously does nothing, and will always return with err == nil.
func (nw *nullWriter) Close() (err error) {

	// NO-OP

	return
}

// Write conforms a nullWriter to an io.Writer, but it writes... nothing. To avoid errors, however, in downstream code it pretends it does (n will *always* == len(b)).
func (nw *nullWriter) Write(b []byte) (n int, err error) {

	if b == nil {
		return
	}
	n = len(b)

	return
}

// WriteByte conforms to an io.ByteWriter but again... nothing is actually written anywhere.
func (nw *nullWriter) WriteByte(c byte) (err error) {

	// NO-OP

	_ = c

	return
}

/*
WriteRune conforms to the other Loggers. It WILL return the proper value for n (matching (bytes.Buffer).WriteRune() and (bufio.Writer).WriteRune() signatures,
and it WILL return an ErrInvalidRune if r is not a valid rune, but otherwise it will no-op.
*/
func (nw *nullWriter) WriteRune(r rune) (n int, err error) {

	n = utf8.RuneLen(r)
	if n < 0 {
		err = ErrInvalidRune
		n = 0
		return
	}

	return
}

// WriteString conforms to an io.StringWriter but nothing is actually written. (n will *always* == len(s))
func (nw *nullWriter) WriteString(s string) (n int, err error) {

	n = len(s)

	return
}