/*
   Copyright (c) 2016 VMware, Inc. All Rights Reserved.
   Licensed under the Apache License, Version 2.0 (the "License");
   you may not use this file except in compliance with the License.
   You may obtain a copy of the License at

       http://www.apache.org/licenses/LICENSE-2.0

   Unless required by applicable law or agreed to in writing, software
   distributed under the License is distributed on an "AS IS" BASIS,
   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
   See the License for the specific language governing permissions and
   limitations under the License.
*/

package dao

import (
	"errors"
	"fmt"
	"net"

	"time"

	"github.com/astaxie/beego/orm"
	_ "github.com/go-sql-driver/mysql" //register mysql driver
	"github.com/vmware/harbor/utils/log"
)

type mysql struct {
	host     string
	port     string
	usr      string
	pwd      string
	database string
}

// NewMySQL returns an instance of mysql
func NewMySQL(host, port, usr, pwd, database string) Database {
	return &mysql{
		host:     host,
		port:     port,
		usr:      usr,
		pwd:      pwd,
		database: database,
	}
}

// Register registers MySQL as the underlying database used
func (m *mysql) Register(alias ...string) error {
	if err := m.testConn(m.host, m.port); err != nil {
		return err
	}

	if err := orm.RegisterDriver("mysql", orm.DRMySQL); err != nil {
		return err
	}

	an := "default"
	if len(alias) != 0 {
		an = alias[0]
	}
	conn := fmt.Sprintf("%s:%s@tcp(%s:%s)/%s", m.usr,
		m.pwd, m.host, m.port, m.database)
	return orm.RegisterDataBase(an, "mysql", conn)
}

func (m *mysql) testConn(host, port string) error {
	ch := make(chan int, 1)
	go func() {
		var err error
		var c net.Conn
		for {
			c, err = net.DialTimeout("tcp", host+":"+port, 20*time.Second)
			if err == nil {
				c.Close()
				ch <- 1
			} else {
				log.Errorf("failed to connect to db, retry after 2 seconds :%v", err)
				time.Sleep(2 * time.Second)
			}
		}
	}()
	select {
	case <-ch:
		return nil
	case <-time.After(60 * time.Second):
		return errors.New("failed to connect to database after 60 seconds")
	}
}

// Name returns the name of MySQL
func (m *mysql) Name() string {
	return "MySQL"
}

// String returns the details of database
func (m *mysql) String() string {
	return fmt.Sprintf("type-%s host-%s port-%s user-%s database-%s",
		m.Name(), m.host, m.port, m.usr, m.database)
}