package models

import "strings"

// Slugify turns text into a slug by the rule the admin form's slug preset
// uses: lower-case ASCII letters and digits are kept, every run of other
// characters becomes one hyphen, and there is no hyphen at either end.
// Letters outside ASCII are not transliterated; they count as other
// characters. A text without a letter or digit gives the empty string.
func Slugify(text string) string {
	var b strings.Builder
	b.Grow(len(text))
	gap := false
	for _, r := range strings.ToLower(text) {
		if (r >= 'a' && r <= 'z') || (r >= '0' && r <= '9') {
			if gap && b.Len() > 0 {
				b.WriteByte('-')
			}
			gap = false
			b.WriteRune(r)
			continue
		}
		gap = true
	}
	return b.String()
}