package main

import (
	"database/sql"
	"log"
	"strconv"
	"sync"
	"time"

	"github.com/Pallinder/go-randomdata"
	_ "github.com/go-sql-driver/mysql"
)

func GetConnect(port int) *sql.DB {

	mysqluri := "root:yame123456@tcp(localhost:" + strconv.Itoa(port) + ")/yame"
	db, err := sql.Open("mysql", mysqluri)
	if err != nil {
		panic(err)
	}

	err = db.Ping()
	if err != nil {
		panic(err)
	}
	return db

}

func dbUpdate(db *sql.DB, names []string) {

	now := time.Now()
	N := 1

	for i := 0; i < N; i++ {
		for _, name := range names {
			tx, err := db.Begin()
			if err != nil {
				panic(err)
			}

			age := strconv.Itoa(randomdata.Number(0, 105))
			level := strconv.Itoa(randomdata.Number(0, 10))
			attr := randomdata.Address()
			tx.Exec("update user set age = ?, level = ?, attr =  ?  where name = ?", age, level, attr, name)

			err = tx.Commit()
			if err != nil {
				panic(err)
			}

		}
	}

	log.Println(int64(len(names)*N)/(time.Now().Unix()-now.Unix()), " update qps")
}

func updateTask(port int, wg *sync.WaitGroup) {
	defer wg.Done()
	db := GetConnect(port)
	dbUpdate(db, RandomSelectNames(db))
}

func RandomSelectNames(db *sql.DB) []string {

	var names []string
	COUNT := 1000

	for i := 0; i < COUNT; i++ {
		age := randomdata.Number(0, 105)
		taskid := randomdata.Number(0, 1000)
		offset := randomdata.Number(0, 100)

		rows, err := db.Query("select * from (select name from user where taskid = ? and age = ?  limit 1000 OFFSET ?)t1 order by rand() ", taskid, age, offset)
		if err != nil {
			panic(err)
		}

		for rows.Next() {
			var name string
			rows.Scan(&name)
			names = append(names, name)
		}
	}

	log.Println(len(names))
	return names
}

func Updating() {
	gcount := 50
	wg := &sync.WaitGroup{}
	wg.Add(gcount)

	for i := 0; i < gcount; i++ {
		go updateTask(3306, wg)
	} // DBInsert(23306)

	wg.Wait()
	log.Println("gthread: ", gcount)
}