package q5

import (
	"database/sql"
	"fmt"
	_ "github.com/go-sql-driver/mysql"
)

type Mysql struct {
	host     string
	port     int32
	user     string
	passwd   string
	database string
	db       *sql.DB
	maxOpenConns int32
	maxIdleConns int32
}

func (this *Mysql) init(host string, port int32, user string, passwd string, database string,
	maxOpenConns int32, maxIdleConns int32) {
	this.host = host
	this.port = port
	this.user = user
	this.passwd = passwd
	this.database = database
	this.maxOpenConns = maxOpenConns
	this.maxIdleConns = maxIdleConns
}

func (this *Mysql) Open() error {
	connStr := fmt.Sprintf("%s:%s@tcp(%s:%d)/%s?charset=utf8",
		this.user,
		this.passwd,
		this.host,
		this.port,
		this.database)
	db, err := sql.Open("mysql", connStr)
	this.db = db
	if err == nil {
		this.db.SetMaxOpenConns(int(this.maxOpenConns))
		this.db.SetMaxIdleConns(int(this.maxIdleConns))
	}
	return err
}

func (this *Mysql) Close() {
	if this.db != nil {
		this.db.Close()
	}
}

func (this *Mysql) Ping() error {
	return this.db.Ping()
}

func (this *Mysql) Query(query string, args ...interface{}) (*sql.Rows, error) {
	rows, err := this.db.Query(query, args...)
	return rows, err
}

/*
func (this *Mysql) QueryRow(query string, args ...interface{}) *sql.Row {
	return this.db.QueryRow(query, args...)
}
*/

func (this *Mysql) Exec(query string, args ...interface{}) (sql.Result, error) {
	result, err := this.db.Exec(query, args...)
	return result, err
}

func NewMysql(host string, port int32, user string, passwd string, database string, maxOpenConns int32, maxIdleConns int32) *Mysql {
	conn := new(Mysql)
	conn.init(host, port, user, passwd, database, maxOpenConns, maxIdleConns)
	return conn
}