package textedit

import "unicode"

type singleLineState struct {
	started     bool
	currentWord []rune
}

func singleLineEdit(r rune, s singleLineState) ([]rune, singleLineState) {
	if !unicode.IsSpace(r) || r == nonbreakSpace {
		s.currentWord = append(s.currentWord, r)
		return nil, s
	}

	if len(s.currentWord) == 0 {
		return nil, s
	}

	ret := s.currentWord
	if s.started {
		ret = append([]rune{' '}, ret...)
	}

	s.currentWord = nil
	s.started = true
	return ret, s
}

func singleLineReleaseState(s singleLineState) []rune {
	if len(s.currentWord) == 0 {
		return nil
	}

	var ret []rune
	if s.started {
		ret = append(ret, ' ')
	}

	return append(ret, s.currentWord...)
}

func singleLine() Editor {
	return Func(singleLineEdit, singleLineReleaseState)
}