package main

import (
	"bytes"
	"encoding/json"
	"fmt"
	"log"
	"net/http"
	"os"
	"queues-go/app/routers"
	client "queues-go/app/storage/mongo"
	tasks "queues-go/app/storage/mongo/collections"
	"strconv"
	"sync"
	"time"
)

func writeMetric(timestamp time.Time, endpoint string, statusCode int, responseTime int, method string) {
	loc, _ := time.LoadLocation("Europe/Moscow")
	s := fmt.Sprintf(
		`{"timestamp":"%s","service":"queues","environment":"%s","endpoint":"%s","status_code":%s,"response_time":%s,"method":"%s"}`,
		timestamp.In(loc).Format("2006-01-02T15:04:05Z"),
		os.Getenv("STAGE"),
		endpoint,
		strconv.Itoa(statusCode),
		strconv.Itoa(responseTime),
		method,
	)
	data := []byte(s)
	r := bytes.NewReader(data)
	_, err := http.Post("http://monitoring:1237/api/v1/metrics/endpoint", "application/json", r)
	if err != nil {
		log.Printf("Error sending metrics %s", err.Error())
	}
}

func handlerWrapper(f func(*http.Request) (interface{}, int)) func(http.ResponseWriter, *http.Request) {
	return func(w http.ResponseWriter, r *http.Request) {
		start := time.Now()
		response, status := f(r)
		if response != nil {
			data, err := json.Marshal(response)
			if err != nil {
				log.Printf("Error marshalling response")
				status = http.StatusInternalServerError
			}
			w.WriteHeader(status)
			w.Write(data)
		} else {
			w.WriteHeader(status)
		}
		go writeMetric(start, r.URL.Path, status, int(time.Since(start).Milliseconds()), r.Method)
		log.Printf("%s %d %s", r.URL, status, time.Since(start))
	}
}

func metricProxy(w http.ResponseWriter, r *http.Request) {
	http.Post("http://monitoring:1237/api/v1/metrics/task", "application/json", r.Body)
	w.WriteHeader(202)
}

func writeCount() {
	for {
		count, err := tasks.Count()
		if err != nil {
			log.Printf("Failed getting docs count: %s", err.Error())
		} else {
			loc, _ := time.LoadLocation("Europe/Moscow")
			s := fmt.Sprintf(
				`{"timestamp":"%s","service":"queues","environment":"%s","name":"tasks","count":%s}`,
				time.Now().In(loc).Format("2006-01-02T15:04:05Z"),
				os.Getenv("STAGE"),
				strconv.Itoa(int(*count)),
			)
			data := []byte(s)
			r := bytes.NewReader(data)
			_, err := http.Post("http://monitoring:1237/api/v1/metrics/increment", "application/json", r)
			if err != nil {
				log.Printf("ERROR %s", err.Error())
			}
		}
		time.Sleep(time.Second)
	}
}

func main() {
	client.Connect()
	routers.MutexMap = make(map[string]*sync.Mutex)
	http.HandleFunc("/api/v1/take", handlerWrapper(routers.Take))
	http.HandleFunc("/api/v1/finish", handlerWrapper(routers.Finish))
	http.HandleFunc("/api/v1/put", handlerWrapper(routers.Put))
	http.HandleFunc("/api/v1/metric", metricProxy)
	log.Printf("Server started")
	go writeCount()
	http.ListenAndServe(":1239", nil)
}