package emoji

// Fragment is either a rune or an emoji
type Fragment struct {
	Offset  int
	IsEmoji bool
	Emoji   Emoji
	Rune    rune
}

// Iterate iterates through a string and returns its runes (for characters) and emojis
func (em Table) Iterate(str string) <-chan Fragment {
	c := make(chan Fragment)
	go func() {
		nextchar := 0
		for index, r := range str {
			// Check if we need to skip entries
			if nextchar > index {
				continue
			}
			// Check if rune is an emoji
			if em.IsEmoji(r) {
				icon := em.Find(str[index:])
				if icon != nil {
					nextchar = index + icon.Length() - 1
					c <- Fragment{
						IsEmoji: true,
						Offset:  index,
						Emoji:   *icon,
					}
					continue
				}
			}
			c <- Fragment{
				IsEmoji: false,
				Offset:  index,
				Rune:    r,
			}
		}
		close(c)
	}()
	return c

}