package session

import (
	"encoding/gob"
	"errors"
	"fmt"
	"net/http"

	"code.gitea.io/sdk/gitea"
	"github.com/gorilla/sessions"
	"github.com/markbates/goth/gothic"
)

const (
	sessionCookie = "_gistea_session"
	infoKey       = "_gistea_info"
)

type Store struct {
	Store    sessions.Store
	GiteaURL string
}

type Info struct {
	Org   string
	Token string
}

func init() {
	gob.Register(&Info{})
}

func (s *Store) RequireAuth(next http.Handler) http.Handler {
	return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
		sess, err := s.Store.Get(r, sessionCookie)
		if err != nil {
			http.Error(w, err.Error(), http.StatusInternalServerError)
			return
		}

		if _, ok := sess.Values[infoKey]; !ok {
			gothic.BeginAuthHandler(w, r)
			return
		}

		next.ServeHTTP(w, r)
	})
}

func (s *Store) Info(r *http.Request) (*Info, error) {
	sess, err := s.Store.Get(r, sessionCookie)
	if err != nil {
		return nil, err
	}
	if infoAny, ok := sess.Values[infoKey]; ok {
		if info, ok := infoAny.(*Info); ok {
			return info, nil
		}
	}
	return nil, errors.New("could not get session info")
}

func (s *Store) HasAuth(r *http.Request) bool {
	i, _ := s.Info(r)
	return i != nil
}

func (s *Store) CompleteAuth(w http.ResponseWriter, r *http.Request, token string) error {
	client, err := gitea.NewClient(s.GiteaURL, gitea.SetToken(token))
	if err != nil {
		return err
	}
	profile, _, err := client.GetMyUserInfo()
	if err != nil {
		return err
	}
	org := fmt.Sprintf("%s-gists", profile.UserName)

	_, resp, err := client.GetOrg(org)
	if err != nil {
		if resp != nil && resp.StatusCode == http.StatusNotFound {
			if _, _, err := client.CreateOrg(gitea.CreateOrgOption{
				Name:       org,
				Visibility: gitea.VisibleTypePublic,
			}); err != nil {
				return err
			}
		} else {
			return err
		}
	}

	sess, err := s.Store.New(r, sessionCookie)
	if err != nil {
		return err
	}

	sess.Values[infoKey] = &Info{
		Org:   org,
		Token: token,
	}
	return s.Store.Save(r, w, sess)
}

func (s *Store) Repos(r *http.Request) ([]*gitea.Repository, error) {
	info, err := s.Info(r)
	if err != nil {
		return nil, err
	}

	client, err := gitea.NewClient(s.GiteaURL, gitea.SetToken(info.Token))
	if err != nil {
		return nil, err
	}

	repos, _, err := client.ListOrgRepos(info.Org, gitea.ListOrgReposOptions{})
	return repos, err
}

func NewStore(sessionSecret, giteURL string) *Store {
	store := sessions.NewCookieStore([]byte(sessionSecret))
	return &Store{
		Store:    store,
		GiteaURL: giteURL,
	}
}