package main

import (
	"encoding/json"
	"errors"

	"github.com/xujiajun/nutsdb"
)

func ReadUser(username string) (*UserData, error) {
	data, err := DbRead(bucketUsers, username)
	if err != nil {
		return nil, err
	}
	var user UserData
	err = json.Unmarshal(data, &user)
	return &user, err
}

func SaveUser(user *UserData) error {
	data, err := json.Marshal(user)
	if err != nil {
		return err
	}
	if user.Username == "" {
		return errors.New("user empty")
	}
	err = DbSave(bucketUsers, user.Username, data)
	return err
}

func DbClean() error {
	err := db.Update(
		func(tx *nutsdb.Tx) error {
			return db.Merge()
		})
	return err
}

func DbSave(bucket, key string, val []byte) error {
	err := db.Update(
		func(tx *nutsdb.Tx) error {
			keyBytes := []byte(key)
			return tx.Put(bucket, keyBytes, val, nutsdb.Persistent)
		})
	return err
}

func DbRead(bucket, key string) ([]byte, error) {
	var val []byte
	err := db.View(
		func(tx *nutsdb.Tx) error {
			keyBytes := []byte(key)
			e, err := tx.Get(bucket, keyBytes)
			if err != nil {
				return err
			}
			val = make([]byte, len(e.Value))
			copy(val, e.Value)
			return err
		})
	return val, err
}

func DbDelete(bucket, key string, val []byte) error {
	err := db.Update(
		func(tx *nutsdb.Tx) error {
			keyBytes := []byte(key)
			return tx.Delete(bucket, keyBytes)
		})
	return err
}