package app

import (
	"strings"
	"unicode/utf8"

	"github.com/geo-platform/tenant-api/internal/shared/response"
)

const (
	kolDisplayNameMaxLen = 40
	kolBioMaxLen         = 500
	kolAvatarURLPrefix   = "/api/public/assets/"
)

func validateKolDisplayName(raw string) (string, error) {
	v := strings.TrimSpace(raw)
	if v == "" {
		return "", response.ErrBadRequest(40001, "kol_profile_invalid_display_name", "display_name is required")
	}
	if utf8.RuneCountInString(v) > kolDisplayNameMaxLen {
		return "", response.ErrBadRequest(40001, "kol_profile_invalid_display_name", "display_name must be at most 40 characters")
	}
	return v, nil
}

func validateKolBio(raw *string) (*string, error) {
	if raw == nil {
		return nil, nil
	}
	v := strings.TrimSpace(*raw)
	if v == "" {
		return nil, nil
	}
	if utf8.RuneCountInString(v) > kolBioMaxLen {
		return nil, response.ErrBadRequest(40002, "kol_profile_invalid_bio", "bio must be at most 500 characters")
	}
	return &v, nil
}

func validateKolAvatarURL(raw *string) (*string, error) {
	if raw == nil {
		return nil, nil
	}
	v := strings.TrimSpace(*raw)
	if v == "" {
		return nil, nil
	}
	if !strings.HasPrefix(v, kolAvatarURLPrefix) {
		return nil, response.ErrBadRequest(40003, "kol_profile_invalid_avatar_url", "avatar_url must be an asset path served by this service")
	}
	return &v, nil
}