package main

import (
	"errors"
	"os"
	"os/signal"
	"runtime"
	"syscall"
	"time"

	"amuz.es/src/infra/cpu_ctrl/daemon"
	"amuz.es/src/infra/cpu_ctrl/logger"
	"amuz.es/src/infra/cpu_ctrl/processor"
	"amuz.es/src/infra/cpu_ctrl/util"
	"amuz.es/src/infra/cpu_ctrl/consumer"

	"gopkg.in/alecthomas/kingpin.v2"
)

var (
	app      = kingpin.New("cpu_ctrl", "Interactive CPU fan controller").Author("Sangbum Kim")
	verbose  = app.Flag("verbose", "Enable verbose mode.").Short('v').Bool()
	P        = app.Flag("proportional-gain", "Set proportional gain value.").Short('p').Default("1.5").Float64()
	I        = app.Flag("integral-gain", "Set integral gain value.").Short('i').Default("0.4").Float64()
	D        = app.Flag("derivative-gain", "Set derivative gain value.").Short('d').Default("2.0").Float64()
	SetPoint = app.Flag("set-point", "Set pointe tempeture").Short('t').Default("38.0").Float64()

	log = logger.NewLogger("cpu_ctrl")
)

func init() {
	app.Version("0.3")
	if _, err := app.Parse(os.Args[1:]); err != nil {
		panic(err)
	}
	logger.InitLogger(*verbose, "", &logger.Config{FileName: "Stderr"})

	setMaxProcs()
}

func setMaxProcs() {
	// TODO(vmarmol): Consider limiting if we have a CPU mask in effect.
	// Allow as many threads as we have cores unless the user specified a value.
	var numProcs int
	// if *maxProcs < 1 {
	numProcs = runtime.NumCPU()
	// } else {
	// numProcs = *maxProcs
	// }
	runtime.GOMAXPROCS(numProcs)

	// Check if the setting was successful.
	actualNumProcs := runtime.GOMAXPROCS(0)
	if actualNumProcs != numProcs {
		log.Printf("Specified max procs of %v but using %v\n", numProcs, actualNumProcs)
	}
}

func FanoutSpeed(sender <-chan processor.FanspeedInfo, handler util.Handler, receivers ...chan<- processor.FanspeedInfo) {
	defer handler.DecreaseWait()
	defer func() {
		if err := recover(); err != nil {
			handler.NotifyError(err.(error))
		}
	}()
	for {
		select {
		case tempeture := <-sender:
			for _, receiver := range receivers {
				select {
				case receiver <- tempeture:
				default:
					log.Warn("Some Tempeture consumer blocked!")
				}
			}
		case <-handler.Done():
			return
		}
	}
}

func FanoutTempeture(sender <-chan processor.TempetureInfo, handler util.Handler, receivers ...chan<- processor.TempetureInfo) {
	defer handler.DecreaseWait()
	defer func() {
		if err := recover(); err != nil {
			handler.NotifyError(err.(error))
		}
	}()
	for {
		select {
		case tempeture := <-sender:
			for _, receiver := range receivers {
				select {
				case receiver <- tempeture:
				default:
					log.Warn("Some Tempeture consumer blocked!")
				}
			}
		case <-handler.Done():
			return
		}
	}
}

func main() {

	var (
		processorCount = processor.GetProcessorCount()
		processors     []processor.Processor
		exitSignal     = make(chan os.Signal, 1)
		handler        = util.NewHandler()
		sampleDuration = time.Second
	)
	log.Infof("Cpu fan controller")

	if processorCount == 0 {
		handler.NotifyError(errors.New("cpu not found!"))
	}
	var (
		tempetureChannel = make(chan processor.TempetureInfo)
		fanspeedChannel  = make(chan processor.FanspeedInfo)
	)
	processors = make([]processor.Processor, 0, processorCount)
	for i := 0; i < processorCount; i++ {
		if info, err := processor.NewProcessorInfo(handler, i, sampleDuration,
			*P, *I, *D, *SetPoint, 0x64, 0x4,
			tempetureChannel, fanspeedChannel,
		);
			err != nil {
			handler.NotifyError(err)
		} else {
			processors = append(processors, info)
			handler.IncreaseWait()
			go info.StartMonitoring()
		}
	}

	fanController := consumer.NewFanControl(processorCount, sampleDuration, handler)
	metricLogger := consumer.NewInfluxMetric("", processorCount, handler)


	handler.IncreaseWait()
	go FanoutTempeture(tempetureChannel, handler, metricLogger.TempetureConsumer())
	defer close(tempetureChannel)

	handler.IncreaseWait()
	go FanoutSpeed(fanspeedChannel, handler, fanController.Consumer(), metricLogger.FanSpeedConsumer())
	defer close(fanspeedChannel)

	handler.IncreaseWait()
	go fanController.StartControl()
	handler.IncreaseWait()
	go metricLogger.StartLogging()

	signal.Notify(exitSignal, syscall.SIGINT, syscall.SIGTERM, syscall.SIGHUP)
	daemon.NotifyDaemon(daemon.DaemonStarted)
	defer daemon.NotifyDaemon(daemon.DaemonStopping)
	defer close(exitSignal)
	defer handler.GracefullWait()

	select {
	case <-handler.Done():
		log.Infoln("Service request to close this application")
	case err := <-handler.Error():
		log.Errorf("%s", err)
	case sysSignal := <-exitSignal:
		log.Warnf("SYSCALL! %s", sysSignal.String())
	}
}