package webservice

import (
	// External
	"github.com/google/uuid"

	// Internal
	"git.gibonuddevalla.se/go/webservice/session"

	// Standard
	"encoding/json"
	"io"
	"net/http"
	"time"
)

type AuthenticationRequest struct {
	UserID     int `json:"-"`
	Username   string
	Password   string
	Additional interface{}
}

type AuthenticationResponse struct {
	OK            bool
	Authenticated bool
	UserID        int
}

type AuthenticationHandler func(AuthenticationRequest, bool) (AuthenticationResponse, error)
type AuthorizationHandler func(*session.T, *http.Request) (bool, error)

func (service *Service) sessionNew(w http.ResponseWriter, r *http.Request, foo *session.T) { // {{{
	var sess session.T
	var found bool
	var err error

	for {
		sess.UUID = uuid.NewString()
		if service.Db == nil {
			if _, found = service.sessions[sess.UUID]; found {
				continue
			}

			sess.Authenticated = false
			sess.Created = time.Now()
			service.sessions[sess.UUID] = &sess
			break

		} else {
			if _, found = service.retrieveSession(sess.UUID); found {
				continue
			}

			err = service.Db.NewSession(sess.UUID)
			if err != nil {
				service.errorHandler(err, "001-A001", w)
				return
			}
			break
		}

	}

	service.logger.Info("session", "op", "new", "uuid", sess.UUID)

	respJSON, _ := json.Marshal(
		struct {
			OK      bool
			Session session.T
		}{
			true,
			sess,
		},
	)

	w.Write(respJSON)
} // }}}
func (service *Service) sessionAuthenticate(w http.ResponseWriter, r *http.Request, sess *session.T) { // {{{
	var authenticatedByFramework bool
	var authResponse AuthenticationResponse
	var err error
	reqBody, _ := io.ReadAll(r.Body)

	// Username and password are provided in this JSON authentication request.
	var authRequest AuthenticationRequest
	err = json.Unmarshal(reqBody, &authRequest)
	if err != nil {
		service.errorHandler(err, "001-0004", w)
		return
	}

	// Authenticate against webservice user table if using a database.
	var userID int
	if service.Db != nil {
		authenticatedByFramework, userID, err = service.Db.Authenticate(authRequest.Username, authRequest.Password)
		if err != nil {
			service.errorHandler(err, "001-A002", w)
			return
		}
		authRequest.UserID = userID
	}

	// The authentication handler is provided with the authenticated response of the possible database authentication,
	// and given a chance to override it.
	authResponse, err = service.authenticationHandler(authRequest, authenticatedByFramework)
	if err != nil {
		service.errorHandler(err, "001-F002", w)
		return
	}
	authResponse.UserID = userID
	authResponse.OK = true
	sess.Authenticated = authResponse.Authenticated

	if authResponse.Authenticated && userID > 0 {
		err = service.Db.SetSessionUser(sess.UUID, userID)
		if err != nil {
			service.errorHandler(err, "001-A003", w)
			return
		}
		service.Db.UpdateUserTime(userID)
	}

	authResp, _ := json.Marshal(authResponse)
	w.Write(authResp)
} // }}}
func (service *Service) sessionRetrieve(w http.ResponseWriter, r *http.Request, sess *session.T) { // {{{
	response := struct {
		OK      bool
		Session *session.T
	}{
		true,
		sess,
	}
	out, _ := json.Marshal(response)
	w.Write(out)
} // }}}

func (service *Service) retrieveSession(uuid string) (session *session.T, found bool) { // {{{
	var err error

	if service.Db == nil {
		session, found = service.sessions[uuid]
		return
	}

	session, err = service.Db.RetrieveSession(uuid)
	if err != nil {
		service.logger.Error("session", "error", err)
		session = nil
		return
	}

	found = (session != nil)
	return
} // }}}