package main

import (
	"fmt"
	"unicode"
)

func cmdgoQuotedisSpaceByte(c byte) bool {
	return c == ' ' || c == '\t' || c == '\n' || c == '\r'
}







func cmdgoQuotedSplit(s string) ([]string, error) {
	
	
	var f []string
	for len(s) > 0 {
		for len(s) > 0 && cmdgoQuotedisSpaceByte(s[0]) {
			s = s[1:]
		}
		if len(s) == 0 {
			break
		}
		
		if s[0] == '"' || s[0] == '\'' {
			quote := s[0]
			s = s[1:]
			i := 0
			for i < len(s) && s[i] != quote {
				i++
			}
			if i >= len(s) {
				return nil, fmt.Errorf("unterminated %c string", quote)
			}
			f = append(f, s[:i])
			s = s[i+1:]
			continue
		}
		i := 0
		for i < len(s) && !cmdgoQuotedisSpaceByte(s[i]) {
			i++
		}
		f = append(f, s[:i])
		s = s[i:]
	}
	return f, nil
}





func cmdgoQuotedJoin(args []string) (string, error) {
	var buf []byte
	for i, arg := range args {
		if i > 0 {
			buf = append(buf, ' ')
		}
		var sawSpace, sawSingleQuote, sawDoubleQuote bool
		for _, c := range arg {
			switch {
			case c > unicode.MaxASCII:
				continue
			case cmdgoQuotedisSpaceByte(byte(c)):
				sawSpace = true
			case c == '\'':
				sawSingleQuote = true
			case c == '"':
				sawDoubleQuote = true
			}
		}
		switch {
		case !sawSpace && !sawSingleQuote && !sawDoubleQuote:
			buf = append(buf, arg...)

		case !sawSingleQuote:
			buf = append(buf, '\'')
			buf = append(buf, arg...)
			buf = append(buf, '\'')

		case !sawDoubleQuote:
			buf = append(buf, '"')
			buf = append(buf, arg...)
			buf = append(buf, '"')

		default:
			return "", fmt.Errorf("argument %q contains both single and double quotes and cannot be quoted", arg)
		}
	}
	return string(buf), nil
}