DELETE watching

nuss.go

@@ -3,6 +3,7 @@ package main
 import (
 	"encoding/json"
 	"errors"
+	"fmt"
 
 	"github.com/xujiajun/nutsdb"
 )
@@ -75,6 +76,50 @@ func AddUserToAnime(username string, userId, animeId int64) (*Anime, error) {
 	return &anime, err
 }
 
+func DeleteUserFromAnime(username string, userId, animeId int64) (*Anime, error) {
+	var anime Anime
+	err := db.Update(
+		func(tx *nutsdb.Tx) error {
+			keyBytes := Int64ToByte(animeId)
+			e, err := tx.Get(bucketAnime, keyBytes)
+			var users []WatchUser
+			if err != nil {
+				users = make([]WatchUser, 0)
+			} else {
+				// parse user list
+				users, err = parseUserList(e.Value)
+				if err != nil {
+					return err
+				}
+
+			}
+			// check if user already part
+			for i, u := range users {
+				// early terminate
+				if u.MalID == userId {
+					// delete user from list
+					users[i] = users[len(users)-1]
+					users = users[:len(users)-1]
+					// check if anime needs recycling
+					anime = Anime{
+						Anime: animeId,
+						Users: users,
+					}
+					if len(users) == 0 {
+						return tx.Delete(bucketAnime, keyBytes)
+					}
+					newData, err := json.Marshal(users)
+					if err != nil {
+						return err
+					}
+					return tx.Put(bucketAnime, keyBytes, newData, nutsdb.Persistent)
+				}
+			}
+			return fmt.Errorf("%s %d schaut nicht %d", username, userId, animeId)
+		})
+	return &anime, err
+}
+
 func ReadAnimes() ([]Anime, error) {
 	var animes []Anime
 	err := db.View(