package ldap

import (
	"forge.cadoles.com/wpetit/goweb/service"
	"github.com/pkg/errors"
	ldap "gopkg.in/ldap.v3"
)

const ServiceName service.Name = "ldap"

type Service struct {
	url string
}

func (s *Service) Search(filter string, opts ...SearchOptionFunc) (*ldap.SearchResult, error) {
	conn, err := s.Connect()
	if err != nil {
		return nil, errors.Wrap(err, "error while connecting to ldap server")
	}
	defer conn.Close()
	return s.SearchConn(conn, filter, opts...)
}

func (s *Service) SearchConn(conn *ldap.Conn, filter string, opts ...SearchOptionFunc) (*ldap.SearchResult, error) {
	options := defaultSearchOptions()
	for _, optFunc := range opts {
		optFunc(options)
	}
	req := ldap.NewSearchRequest(
		options.BaseDN,
		options.Scope,
		options.DerefAliases,
		options.SizeLimit,
		options.TimeLimit,
		options.TypesOnly,
		filter,
		options.Attributes,
		options.Controls,
	)
	result, err := conn.Search(req)
	if err != nil {
		return nil, errors.Wrap(err, "error while executing ldap search")
	}
	return result, nil
}

func (s *Service) Bind(dn, password string) error {
	conn, err := s.Connect()
	if err != nil {
		return errors.Wrap(err, "error while connecting to ldap server")
	}
	defer conn.Close()
	return s.BindConn(conn, dn, password)
}

func (s *Service) BindConn(conn *ldap.Conn, dn, password string) error {
	if err := conn.Bind(dn, password); err != nil {
		return errors.Wrap(err, "error while executing ldap bind")
	}
	return nil
}

func (s *Service) Connect() (*ldap.Conn, error) {
	conn, err := ldap.DialURL(s.url)
	if err != nil {
		return nil, errors.Wrapf(err, "error while dialing ldap url '%s'", s.url)
	}
	return conn, err
}

func (s *Service) ModifyPassword(identity, oldPassword, newPassword string) error {
	conn, err := s.Connect()
	if err != nil {
		return errors.Wrap(err, "error while connecting to ldap server")
	}
	defer conn.Close()
	return s.ModifyPasswordConn(conn, identity, oldPassword, newPassword)
}

func (s *Service) ModifyPasswordConn(conn *ldap.Conn, identity, oldPassword, newPassword string) error {
	req := ldap.NewPasswordModifyRequest("", oldPassword, newPassword)
	if _, err := conn.PasswordModify(req); err != nil {
		return errors.Wrap(err, "error while modifying password")
	}
	return nil
}

// From retrieves the ldap service in the given container
func From(container *service.Container) (*Service, error) {
	service, err := container.Service(ServiceName)
	if err != nil {
		return nil, errors.Wrapf(err, "error while retrieving '%s' service", ServiceName)
	}
	srv, ok := service.(*Service)
	if !ok {
		return nil, errors.Errorf("retrieved service is not a valid '%s' service", ServiceName)
	}
	return srv, nil
}

// Must retrieves the ldap service in the given container or panic otherwise
func Must(container *service.Container) *Service {
	srv, err := From(container)
	if err != nil {
		panic(err)
	}
	return srv
}