package webutil

import (
	"errors"
	"net/url"
	"reflect"
)

// ScanStruct scans form values into the exported fields of dest (must be a
// pointer to a struct) using field names as form keys. Bool fields are set to
// true when the key is present, matching HTML checkbox behaviour.
func ScanStruct(form url.Values, dest any) error {
	v := reflect.ValueOf(dest)
	if v.Kind() != reflect.Ptr || v.Elem().Kind() != reflect.Struct {
		return errors.New("ScanStruct: dest must be a pointer to a struct")
	}
	v = v.Elem()

	s := NewFormScanner(form)
	for key := range form {
		fv := v.FieldByName(key)
		if !fv.IsValid() || !fv.CanSet() {
			continue
		}
		s.Scan(key, fv.Addr().Interface())
	}
	return s.Error()
}