package db

import (
	"errors"
	"fmt"
	"os"
	"os/exec"
	"path/filepath"
	"strings"
	"sync"
)

var Dbconn *Conn
var sy sync.Mutex

func init() {
	GetConn()
}

// get Conn of db for do execute.
func GetConn() error {
	var err error
	path, err := GetCurrentPath()
	if err != nil {
		return errors.New("get current path error")
	}

	filepath := fmt.Sprintf("%stest.db", path)
	fmt.Println("self: ========>", filepath)
	db, err := New(filepath, "", false)
	if err != nil {
		fmt.Println("new db database: ", err)
		return err
	}
	Dbconn, err = db.Connect()
	if err != nil {
		fmt.Println("new db conn error; ", err)
		return err
	}
	return nil
}

//bak dbdata.
func BakDbFile() (string, error) {

	path, err := GetCurrentPath()
	if err != nil {
		return "", errors.New("get current path error")
	}

	filepath := fmt.Sprintf("%stmptest.db", path)
	db, err := New(filepath, "", false)
	if err != nil {
		fmt.Println("new db database: ", err)
		return "", err
	}

	tmpconn, err := db.Connect()
	if err != nil {
		fmt.Println("new db conn error; ", err)
		return "", err
	}
	defer tmpconn.Close()

	err = Dbconn.Backup(tmpconn)
	if err != nil {
		return "", err
	}
	return filepath, nil
}

// do exet when get querystring.
func DoExecute(executestring []string) ([]*Result, error) {
	sy.Lock()
	defer sy.Unlock()
	allResults, err := Dbconn.Execute(executestring, false, false)
	if err != nil {
		fmt.Println("execute error!", err)
		return nil, err
	}
	return allResults, nil
}

// get current path
func GetCurrentPath() (string, error) {
	file, err := exec.LookPath(os.Args[0])
	if err != nil {
		return "", err
	}
	path, err := filepath.Abs(file)
	if err != nil {
		return "", err
	}
	i := strings.LastIndex(path, "/")
	if i < 0 {
		i = strings.LastIndex(path, "\\")
	}
	if i < 0 {
		return "", errors.New(`error: Can't find "/" or "\".`)
	}
	return string(path[0 : i+1]), nil
}

func Dumpdb() {

	var b strings.Builder
	if err := Dbconn.Dump(&b); err != nil {
		fmt.Println("dump file ", err.Error())
	}
	fmt.Printf("%T\n", b)
}