package main

import (
    "bytes"
    "fmt"
    "log"
    "net/http"
    "time"
    "io/ioutil"
    "bufio"
    "strings"
)

// metrics handler

func metricsHandler(response http.ResponseWriter, request *http.Request) {
        name := getUserName(request)
        if name  != "" {
           url := "http://localhost:9999/api/v2/query?org=beieliorg"
           data := []byte(`from(bucket:"beielibucket") |> range(start:-24h) |> filter(fn: (r) => r._field == "v") |> filter(fn: (r) => r.devaddr == "084B3824")`)

           req, err := http.NewRequest("POST", url, bytes.NewBuffer(data))
	   if err != nil {
		log.Fatal("Error reading request. ", err)
           } 
 
	   // Set headers
	   req.Header.Set("Authorization", "Token xXnq8ADcDygAyM_L0B_10c9yuoOv-cYcUfIXkJunRrIDMhB5ZNmza-Whr1ELcbKNzW8GzUMMYD85QohUHQdAmg==")
	   req.Header.Set("accept", "application/csv")
	   req.Header.Set("content-type", "application/vnd.flux")
 
	   // Set client timeout
	   client := &http.Client{Timeout: time.Second * 10}
 
	   // Send request
	   resp, err := client.Do(req)
	   if err != nil {
		log.Fatal("Error reading response. ", err)
	   }
	   defer resp.Body.Close()
 
	   fmt.Println("response Status:", resp.Status)
	   fmt.Println("response Headers:", resp.Header)

           body, err := ioutil.ReadAll(resp.Body)
	   if err != nil {
		log.Fatal("Error reading body. ", err)
	   }
           
           fmt.Fprintf(response,"[\n") 
           scanner := bufio.NewScanner(strings.NewReader(string(body)))
           first := true
           for scanner.Scan() {
               s := strings.Split(scanner.Text(),",")
               if ((len(s) >= 7) && !(strings.HasPrefix(s[5],"_"))) {
                   t,err := time.Parse(time.RFC3339,s[5])
                   if err != nil {
                         continue
                   }
                   a := t.Unix()
                   b := s[6]
                   if !(first) {
                       fmt.Fprintf(response,",") 
                   } else {
                     first = false
                   }
                   fmt.Fprintf(response,"[%d000,%s]\n",a,b) 
               }
           }
           fmt.Fprintf(response,"]\n") 

        } else {
	   fmt.Fprintf(response, "{ \"msg\": \"Only available for logged in users\" }")
        }
}