package activitypub

import (
	"context"
	"encoding/json"
	"fmt"
	"net/http"
	"strconv"

	webutils "git.mstar.dev/mstar/goutils/http"
	"github.com/rs/zerolog/hlog"
	"gorm.io/gorm"

	"git.mstar.dev/mstar/linstrom/activitypub"
	"git.mstar.dev/mstar/linstrom/storage-new"
	"git.mstar.dev/mstar/linstrom/storage-new/dbgen"
	"git.mstar.dev/mstar/linstrom/storage-new/models"
)

type ActivityFollowOut struct {
	Context any    `json:"@context,omitempty"`
	Id      string `json:"id"`
	Type    string `json:"type"`
	Actor   string `json:"actor"`
	Object  any    `json:"object"`
}

func activityFollow(w http.ResponseWriter, r *http.Request) {
	log := hlog.FromRequest(r)
	id := r.PathValue("id")
	activity, err := FollowFromStorage(r.Context(), id)
	switch err {
	case gorm.ErrRecordNotFound:
		_ = webutils.ProblemDetailsStatusOnly(w, http.StatusNotFound)
	case nil:
		activity.Context = activitypub.BaseLdContext
		data, err := json.Marshal(activity)
		if err != nil {
			log.Error().Err(err).Any("activity", activity).Msg("Failed to marshal create activity")
			_ = webutils.ProblemDetailsStatusOnly(w, http.StatusInternalServerError)
			return
		}
		w.Header().Add("Content-Type", "application/activity+json")
		_, _ = fmt.Fprint(w, string(data))
	default:
		if storage.HandleReconnectError(err) {
			log.Error().Err(err).Msg("Connection failed, restart attempt started")
		} else {
			log.Error().Err(err).Msg("Failed to get create activity from db")
		}
		_ = webutils.ProblemDetailsStatusOnly(w, http.StatusInternalServerError)
	}
}

func FollowFromStorage(ctx context.Context, id string) (*ActivityFollowOut, error) {
	ac := dbgen.Activity
	u2u := dbgen.UserToUserRelation
	u := dbgen.User
	// log := log.Ctx(ctx)
	activity, err := ac.Where(ac.Id.Eq(id), ac.Type.Eq(string(models.ActivityFollow))).First()
	if err != nil {
		return nil, err
	}
	followId, err := strconv.ParseUint(activity.ObjectId, 10, 64)
	if err != nil {
		return nil, err
	}
	relation, err := u2u.Where(u2u.ID.Eq(followId)).First()
	if err != nil {
		return nil, err
	}
	follower, err := u.Where(u.ID.Eq(relation.UserId)).Preload(u.RemoteInfo).First()
	if err != nil {
		return nil, err
	}
	followed, err := u.Where(u.ID.Eq(relation.TargetUserId)).Preload(u.RemoteInfo).First()
	if err != nil {
		return nil, err
	}
	out := ActivityFollowOut{
		Id:   id,
		Type: "Follow",
	}
	if follower.RemoteInfo != nil {
		out.Actor = follower.RemoteInfo.ApLink
	} else {
		out.Actor = activitypub.UserIdToApUrl(follower.ID)
	}
	if followed.RemoteInfo != nil {
		out.Object = followed.RemoteInfo.ApLink
	} else {
		out.Object = activitypub.UserIdToApUrl(followed.ID)
	}
	return &out, nil
}