// Package wordcount counts words in text.
package wordcount
import (
	"strings"
	"unicode"
)
// Frequency counts the occurance of each word.
type Frequency map[string]int
// WordCount returns the Frequency of words in input.
func WordCount(input string) Frequency {
	ret := make(Frequency)
	input = strings.ReplaceAll(input, "$", " ")
	input = strings.ReplaceAll(input, "^", " ")
	input = strings.ToLower(input)
	for _, word := range strings.FieldsFunc(input, sepFunc) {
		ret[strings.Trim(word, "'")]++
	}
	return ret
}
func sepFunc(ch rune) bool {
	if unicode.IsSpace(ch) || unicode.IsPunct(ch) && ch != '\'' {
		return true
	}
	return false
}

	"sort"

	"unicode/utf8"

// Detect returns a list of anagrams for input from candidates.
func Detect(input string, candidates []string) []string {
	var ret []string

func Detect(subject string, wl []string) (res []string) {
	subject = strings.ToLower(subject)
	base := string_sort(subject)

	input = strings.ToLower(input)
	for _, word := range candidates {
		if checkCandidate(input, strings.ToLower(word)) {
			ret = append(ret, word)

	for i, w := range wl {
		w = strings.ToLower(w)
		if subject == w || base != string_sort(w) {
			continue

		res = append(res, wl[i])

	return ret

	return res

func checkCandidate(letters string, candidate string) bool {
	// check for self anagram
	if letters == candidate {
		return false
	}
	for _, ch := range candidate {
		if i := strings.IndexRune(letters, ch); i != -1 {
			// remove the mathing rune from letters
			letters = letters[:i] + letters[i+utf8.RuneLen(ch):]
			continue
		}
		return false
	}
	// we have found all the letters and there are no runes left
	if letters == "" {
		return true
	}
	return false

func string_sort(s string) string {
	split := strings.Split(s, "")
	sort.Strings(split)
	return strings.Join(split, "")