package main

import (
	"flag"
	"fmt"
	"hash/crc32"
	"io"
	"io/ioutil"
	"tickserver/api/lmaxapi"
	"tickserver/api/lmaxapi/main/common"
	"tickserver/api/lmaxapi/request"
	"tickserver/api/lmaxapi/response"
	"log"
	"net/url"
	"os"
	"path"
	"runtime"
	"time"
    "strconv"
)

var ty = flag.String("t", "tick", "tick or M1")
var bookId = flag.String("bookid", "4001", "lmax book id")

func CreateSession() (*lmaxapi.Session, error) {
	lmaxapi.SetBaseUrl("https://trade.lmaxtrader.com")
	req := request.NewLoginRequest("wave2907", "Tg417396", request.ProductType.CFD_LIVE)
	session, err := lmaxapi.Login(req)
	if err == nil {
		log.Println("My accountId is:", session.GetAccountDetails().AccountId)
	}
	return session, err
}

func main() {
	runtime.GOMAXPROCS(runtime.NumCPU())
	common.EnableLog("proto.log")
	flag.Parse()
    session, err := CreateSession()
    if err != nil {
        panic(err)
    }
	session.RegisterHistoricMarketDataEvent(HistoricEvent)
	req := request.NewHistoricSubscriptionRequest()
	session.Subscribe(req, func(err error) {
		if err == nil {
			var req1 lmaxapi.IRequest
			id, err := strconv.Atoi(*bookId)
			if err != nil {
				panic(err)
			}
			if *ty == "tick" {
				req1 = request.NewTopOfBookHistoricRequest(*bookId, int64(id),
					time.Date(2014, 1, 1, 0, 0, 0, 0, time.UTC),
					time.Now(),
					"CSV")
			} else {
				req1 = request.NewAggregateHistoricRequest(*bookId, int64(id),
					time.Date(2014, 1, 1, 0, 0, 0, 0, time.UTC),
					time.Now(),
					"CSV",           //暂时只有一种格式
					"MINUTE",        //还可以 DAY， 也就是只有分钟线 和 日线两种
					[]string{"BID"}) //BID/ASK/TRADE 可以是这三种形式
			}
			session.RequestHistoricMarketData(req1, func(err error) {
				if err != nil {
					fmt.Println("Failed to request historic market data:", err)
				}
			})
		} else {
			fmt.Println("Failed to subscribe:", err)
		}

	})
    sub := request.NewOrderBookSubscriptionRequest(4001)
    session.Subscribe(sub, func(err error) {
        if err != nil {
            log.Println(err)
        }
    })
    common.Heartbeat(session)
	session.Start()
}

func HistoricEvent(s *lmaxapi.Session, event *response.HistoricMarketDataEvent) {
	t := time.Now()
	log.Println("@@@@@@@:len(event.Urls)=", len(event.Urls))
	downerr := downloadAndRetry(s, event.Urls, "./lmax", 2)
	fmt.Println(downerr)
	s.Stop()
	fmt.Println(time.Now().Sub(t))
}

//开始下载历史数据
//1. 下载的策略。30个1组，下载完成一组，进入下一组。
//2. 设置一下保存目录，让数据保存在目录里面。
//3. 如果数据不为空，进行完整性校验。
//4. 如果任务失败，那么重试一次。
type downError struct {
	url string
	err error
}

type work struct {
	url  string
	err  error
	done bool
}

func download(session *lmaxapi.Session, urls []string, dirname string) []downError {
	task, err := newDownTask(session, 20, dirname)
	if err != nil {
		panic(err)
	}
	go func() {
		for i := 0; i < len(urls); i++ {
			task.send(urls[i])
		}
	}()
	var errurl []downError
	for i := 0; i < len(urls); i++ {
		url, err := task.getResponse()
		if err != nil {
			errurl = append(errurl, downError{url, err})
            continue
		}
        log.Println("done", url)
	}
	//结束任务
	task.done()
	return errurl
}

func downloadAndRetry(session *lmaxapi.Session, urls []string, dirname string, retry int) []downError {
	var downerr []downError
	for i := 0; i < retry; i++ {
		downerr = download(session, urls, dirname)
		if downerr == nil {
			return nil
		}
		urls := make([]string, len(downerr))
		for j := 0; j < len(downerr); j++ {
			urls[j] = downerr[j].url
		}
	}
	return downerr
}

type downTask struct {
	maxWork int
	dirname string
	in      chan *work
	out     chan *work
	session *lmaxapi.Session
}

func newDownTask(session *lmaxapi.Session, max int, dirname string) (*downTask, error) {
	task := &downTask{}
	task.maxWork = max
	task.dirname = dirname
	task.session = session
	err := os.MkdirAll(dirname, 0777)
	if err != nil {
		return nil, err
	}
	task.in = make(chan *work)
	task.out = make(chan *work)
	for i := 0; i < max; i++ {
		go task.dowork()
	}
	return task, nil
}

func (task *downTask) dowork() {
	for {
		w := <-task.in
		if w.done == true {
			break
		}
		url := w.url
		task.out <- task.downloadOne(url)
	}
}

func (task *downTask) getResponse() (string, error) {
	w := <-task.out
	return w.url, w.err
}

func (task *downTask) send(url string) {
	task.in <- &work{url, nil, false}
}

func (task *downTask) done() {
	for i := 0; i < task.maxWork; i++ {
		task.in <- &work{"", nil, true}
	}
}

func (task *downTask) downloadOne(u string) *work {
	surl, err := url.Parse(u)
	if err != nil {
		return &work{u, err, false}
	}
	urlpath := surl.Path
	filename := task.dirname + urlpath
	fullpath := path.Dir(filename)
	os.MkdirAll(fullpath, 0777)
	ok := checkFile(filename)
	if ok { //没有必要重新下载数据了
		return &work{u, nil, false}
	} else {
		os.Remove(filename)
	}
	resp, err := task.session.OpenUrl(u, nil)
	// fmt.Println(u)
	if err != nil {
		return &work{u, err, false}
	}
	defer resp.Body.Close()

	//下载数据保存到文件里面
	w, e := os.Create(filename)
	if e != nil {
		return &work{u, e, false}
	}
	_, e = io.Copy(w, resp.Body)
	w.Close()
	if e != nil { //发生错误了
		//删除文件
		os.Remove(filename)
		return &work{u, e, false}
	}
	e = hashfile(filename)
	return &work{u, nil, false}
}

func crc32file(filename string) (uint32, error) {
	crc := crc32.NewIEEE()
	r, err := os.Open(filename)
	if err != nil {
		return 0, err
	}
	defer r.Close()
	_, err = io.Copy(crc, r)
	if err != nil {
		return 0, err
	}
	return crc.Sum32(), nil
}

func hashfile(filename string) error {
	hashsave := filename + ".hash"
	file, err := os.Create(hashsave)
	if err != nil {
		return err
	}
	defer file.Close()
	crc, err := crc32file(filename)
	if err != nil {
		return err
	}
	_, err = file.WriteString(fmt.Sprint(crc))
	if err != nil {
		return err
	}
	return nil
}

func checkFile(local string) bool {
	file, err := os.Open(local)
	if err != nil {
		return false
	}
	defer file.Close()
	stat, err := file.Stat()
	if err != nil {
		return false
	}
	if stat.Size() == 0 {
		return false
	}
	//checksum
	crc := crc32.NewIEEE()
	_, err = io.Copy(crc, file)
	if err != nil {
		return false
	}
	sum := fmt.Sprint(crc.Sum32())
	//compare
	b, err := ioutil.ReadFile(local + ".hash")
	if sum != string(b) {
		return false
	}
	return true
}