package pcspath

import (
	"path"
	"strings"
	"unicode"
)

// EscapeBracketOne 转义中括号, 加一个反斜杠
func EscapeBracketOne(s string) string {
	if !strings.Contains(s, "[") && !strings.Contains(s, "]") {
		return s
	}

	builder := &strings.Builder{}
	for k := range s {
		if s[k] != '[' && s[k] != ']' {
			builder.WriteByte(s[k])
			continue
		}

		if k >= 1 && s[k-1] == '\\' {
			builder.WriteByte(s[k])
			continue
		}
		builder.WriteString(`\`)
		builder.WriteByte(s[k])
	}
	return builder.String()
}

// EscapeBracketTwo 转义中括号, 加两个反斜杠
func EscapeBracketTwo(s string) string {
	if !strings.Contains(s, "[") && !strings.Contains(s, "]") {
		return s
	}

	builder := &strings.Builder{}
	for k := range s {
		if s[k] != '[' && s[k] != ']' {
			builder.WriteByte(s[k])
			continue
		}

		if k >= 2 && s[k-1] == '\\' && s[k-2] == '\\' {
			builder.WriteByte(s[k])
			continue
		}
		builder.WriteString(`\\`)
		builder.WriteByte(s[k])
	}
	return builder.String()
}

// SplitAll 分割路径, "/"为分隔符
func SplitAll(pcspath string) (elem []string) {
	pcspath = path.Clean(pcspath)

	raw := strings.Split(pcspath, "/")

	if !path.IsAbs(pcspath) {
		elem = append(elem, raw[0])
	}

	for k := range raw[1:] {
		elem = append(elem, "/"+raw[k+1])
	}

	return
}

func isSpace(r rune) rune {
	if unicode.IsSpace(r) {
		return r
	}
	return -1
}

// Escape 转义字符串的空白符号, 小括号, 中括号
func Escape(pcspath string) string {
	// 没有空格
	if !strings.ContainsAny(pcspath, "[]()") && strings.IndexFunc(pcspath, unicode.IsSpace) == -1 {
		return pcspath
	}

	var (
		builder = &strings.Builder{}
		isSlash bool
	)
	for _, s := range pcspath {
		switch s {
		case '\\':
			isSlash = !isSlash
			if !isSlash {
				builder.WriteRune('\\')
			}
			continue
		case isSpace(s):
			fallthrough
		case '[', ']', '(', ')':
			builder.WriteString("\\")
			builder.WriteRune(s)
			isSlash = false
			continue
		default:
			isSlash = false
			builder.WriteRune(s)
		}
	}
	return builder.String()
}

// EscapeStrings 转义字符串数组所有元素的空格, 小括号, 中括号
func EscapeStrings(ss []string) {
	for k := range ss {
		ss[k] = Escape(ss[k])
	}
}