package client

import "strings"

func extractScreenshotBase64(out []byte) string {
	s := strings.TrimSpace(string(out))
	s = strings.TrimPrefix(s, "\ufeff")
	best := ""
	for _, part := range strings.Fields(s) {
		var b strings.Builder
		for _, r := range part {
			if (r >= 'A' && r <= 'Z') || (r >= 'a' && r <= 'z') || (r >= '0' && r <= '9') || r == '+' || r == '/' || r == '=' {
				b.WriteRune(r)
			}
		}
		cleaned := b.String()
		if len(cleaned) > len(best) {
			best = cleaned
		}
	}
	if len(best) >= 100 {
		return best
	}
	return strings.Map(func(r rune) rune {
		if (r >= 'A' && r <= 'Z') || (r >= 'a' && r <= 'z') || (r >= '0' && r <= '9') || r == '+' || r == '/' || r == '=' {
			return r
		}
		return -1
	}, s)
}