package storage

import (
	"encoding/json"
	"github.com/dgraph-io/badger/v4"
	"github.com/spf13/viper"
	"time"
)

type BadgerHandler struct {
	db *badger.DB
}

func NewBadgerHandler(cfg *viper.Viper) (*BadgerHandler, error) {
	dbPath := cfg.GetString("storage.kv.badger.dbPath")

	opts := badger.DefaultOptions(dbPath)
	db, err := badger.Open(opts)
	if err != nil {
		return nil, err
	}

	return &BadgerHandler{
		db: db,
	}, nil
}

func (bh *BadgerHandler) Put(k string, v any) error {
	err := bh.db.Update(func(txn *badger.Txn) error {
		bytes, err := json.Marshal(v)
		if err != nil {
			return err
		}
		return txn.Set([]byte(k), bytes)
	})

	return err
}

func (bh *BadgerHandler) PutWithTTL(k string, v any, duration time.Duration) error {
	err := bh.db.Update(func(txn *badger.Txn) error {
		bytes, err := json.Marshal(v)
		if err != nil {
			return err
		}
		entry := badger.NewEntry([]byte(k), bytes).WithTTL(duration)
		return txn.SetEntry(entry)
	})

	return err
}

func (bh *BadgerHandler) Get(k string) (any, error) {
	var value []byte

	err := bh.db.View(func(txn *badger.Txn) error {
		item, err := txn.Get([]byte(k))
		if err != nil {
			return err
		}

		err = item.Value(func(val []byte) error {
			value = make([]byte, len(val))
			copy(value, val)
			return nil
		})

		return err
	})

	if err != nil {
		return nil, err
	}

	var result map[string]interface{}
	err = json.Unmarshal(value, &result)
	if err != nil {
		return nil, err
	}

	return result, nil
}

func (bh *BadgerHandler) Delete(k string) error {
	err := bh.db.Update(func(txn *badger.Txn) error {
		err := txn.Delete([]byte(k))
		return err
	})

	return err
}