package main

import (
	"encoding/json"
	"fmt"
	"log"
	"os"
	"os/signal"
	"sync"
	"time"

	"github.com/ClusterCockpit/cc-metric-collector/collectors"
	protocol "github.com/influxdata/line-protocol"
)

var Collectors = map[string]collectors.MetricGetter{
	"likwid":     &collectors.LikwidCollector{},
	"loadavg":    &collectors.LoadavgCollector{},
	"memstat":    &collectors.MemstatCollector{},
	"netstat":    &collectors.NetstatCollector{},
	"ibstat":     &collectors.InfinibandCollector{},
	"lustrestat": &collectors.LustreCollector{},
}

var serializer *protocol.Encoder

type GlobalConfig struct {
	Sink struct {
		User     string `json:"user"`
		Password string `json:"password"`
		Host     string `json:"host"`
		Port     string `json:"port"`
	} `json:"sink"`
	Interval   int      `json:"interval"`
	Duration   int      `json:"duration"`
	Collectors []string `json:"collectors"`
}

func LoadConfiguration(file string, config *GlobalConfig) error {
	configFile, err := os.Open(file)
	defer configFile.Close()
	if err != nil {
		fmt.Println(err.Error())
	}
	jsonParser := json.NewDecoder(configFile)
	jsonParser.Decode(config)
	return err
}

func shutdown(wg *sync.WaitGroup, config *GlobalConfig) {
	sigs := make(chan os.Signal, 1)
	signal.Notify(sigs, os.Interrupt)

	go func(wg *sync.WaitGroup) {
		<-sigs
		log.Print("Shutdown...")
		for _, c := range config.Collectors {
			col := Collectors[c]
			log.Print("Stop ", col.Name())
			col.Close()
		}
		time.Sleep(1 * time.Second)
		wg.Done()
	}(wg)
}

func setupProtocol(scope string, tags map[string]string, fields map[string]interface{}, t time.Time) {
	cur, err := protocol.New(scope, tags, fields, t)
	if err != nil {
		log.Print(err)
	}
	_, err = serializer.Encode(cur)
	if err != nil {
		log.Print(err)
	}
}

func main() {
	var config GlobalConfig
	var wg sync.WaitGroup
	wg.Add(1)
	host, err := os.Hostname()
	if err != nil {
		log.Print(err)
		return
	}

	LoadConfiguration("config.json", &config)
	if config.Interval <= 0 || time.Duration(config.Interval)*time.Second <= 0 {
		log.Print("Configuration value 'interval' must be greater than zero")
		return
	}
	if config.Duration <= 0 {
		log.Print("Configuration value 'duration' must be greater than zero")
		return
	}
	shutdown(&wg, &config)

	serializer = protocol.NewEncoder(os.Stdout)
	serializer.SetPrecision(time.Second)
	serializer.SetMaxLineBytes(1024)

	for _, c := range config.Collectors {
		col := Collectors[c]
		col.Init()
		log.Print("Start ", col.Name())
	}

	log.Print(config.Interval, time.Duration(config.Interval)*time.Second)
	ticker := time.NewTicker(time.Duration(config.Interval) * time.Second)
	done := make(chan bool)

	nodeFields := make(map[string]interface{})

	slist := collectors.SocketList()
	socketsFields := make(map[int]map[string]interface{}, len(slist))
	for _, s := range slist {
		socketsFields[s] = make(map[string]interface{})
	}

	clist := collectors.CpuList()
	cpuFields := make(map[int]map[string]interface{}, len(clist))
	for _, s := range clist {
		cpuFields[s] = make(map[string]interface{})
	}

	go func() {
		for {
			select {
			case <-done:
				return
			case t := <-ticker.C:
				scount := 0
				ccount := 0

				for _, c := range config.Collectors {
					col := Collectors[c]
					col.Read(time.Duration(config.Duration))

					for key, val := range col.GetNodeMetric() {
						nodeFields[key] = val
					}
					for sid, socket := range col.GetSocketMetrics() {
						for key, val := range socket {
							socketsFields[sid][key] = val
							scount++
						}
					}
					for cid, cpu := range col.GetCpuMetrics() {
						for key, val := range cpu {
							cpuFields[cid][key] = val
							ccount++
						}
					}
				}

				setupProtocol("node", map[string]string{"host": host}, nodeFields, t)

				if scount > 0 {
					for sid, socket := range socketsFields {
						setupProtocol("socket", map[string]string{"socket": fmt.Sprintf("%d", sid), "host": host}, socket, t)
					}
				}

				if ccount > 0 {
					for cid, cpu := range cpuFields {
						setupProtocol("cpu", map[string]string{"cpu": fmt.Sprintf("%d", cid), "host": host}, cpu, t)
					}
				}
			}
		}
	}()

	wg.Wait()
}