package leveldb
 
import (
	"encoding/json"
	"fmt"
 
	"github.com/syndtr/goleveldb/leveldb"
	"github.com/syndtr/goleveldb/leveldb/errors"
	"github.com/syndtr/goleveldb/leveldb/iterator"
	"github.com/syndtr/goleveldb/leveldb/opt"
	"github.com/syndtr/goleveldb/leveldb/util"
)
 
type _leveldb struct {
	DB *leveldb.DB
}
 
//打开Db
func OpenDb(path string) *_leveldb {
	newdb, err := leveldb.OpenFile(path, nil)
	if _, corrupted := err.(*errors.ErrCorrupted); corrupted {
		newdb, err = leveldb.RecoverFile(path, nil)
	}
 
	if err != nil {
		panic(err)
	}
	uleveldb := _leveldb{}
	uleveldb.DB = newdb
	return &uleveldb
}
 
//释放资源
func (uleveldb *_leveldb) Close() {
	uleveldb.DB.Close()
}
 
/**
 * @description: 存储数据
 * @param  {*}
 * @return {*}
 * @param {interface{}} key
 * @param {interface{}} value
 */
func (uleveldb *_leveldb) Put(key string, value interface{}) error {
 
	result, err := json.Marshal(value)
	if err != nil {
		fmt.Println("error")
		return err
	}
	err = uleveldb.DB.Put([]byte(key), []byte(result), nil)
	return err
}
 
/**
 * @description: 读取数据
 * @param  {*}
 * @return {*}
 * @param {interface{}} key
 * @param {interface{}} value
 */
func (uleveldb *_leveldb) Get(key interface{}) ([]byte, error) {
 
	return uleveldb.DB.Get([]byte(key.(string)), nil)
}
 
/**
 * @description: 删除数据
 * @param  {*}
 * @return {*}
 * @param {string} key
 * @param {interface{}} value
 */
func (uleveldb *_leveldb) Delete(key string) error {
 
	return uleveldb.DB.Delete([]byte(key), nil)
}
 
/**
 * @description:  返回指定当前DB迭代器
 * @param  {*}
 * @return {*}
 * @param {string} key
 * @param {interface{}} value
 */
func (uleveldb *_leveldb) NewIterator(slice *util.Range, ro *opt.ReadOptions) iterator.Iterator {
 
	return uleveldb.DB.NewIterator(slice, ro)
}