package discovery

import (
	"fmt"
	"sync"

	"git.loafle.net/commons_go/logging"
	"git.loafle.net/overflow/overflow_discovery/api/module/discovery/model"
)

var discoverer *discovery

func DiscoveryInit() {
	discoverer = &discovery{}
	discoverer.start()
}

func DiscoveryDestroy() {
	discoverer.stop()
	discoverer = nil
}

func DiscoverZone(dz *model.DiscoveryZone) {
	discoverer.discoverZone(dz)
}

func DiscoverHost(dh *model.DiscoveryHost) {
	discoverer.discoverHost(dh)
}

func DiscoverPort(dp *model.DiscoveryPort) {
	discoverer.discoverPort(dp)
}

func DiscoverService(ds *model.DiscoveryService) {
	discoverer.discoverService(ds)
}

func Stop() {

}

type discovery struct {
	sendChan chan interface{}
	errChan  chan error

	stopChan chan struct{}
	stopWg   sync.WaitGroup
}

func (d *discovery) start() {
	if d.stopChan != nil {
		panic("Discovery: discovery is already running. Stop it before starting it again")
	}

	d.stopChan = make(chan struct{})
	d.sendChan = make(chan interface{})
	d.errChan = make(chan error)
	logging.Logger().Info(fmt.Sprintf("Discovery: discovery is started"))

	d.stopWg.Add(1)
	go handle(d)
}

func (d *discovery) stop() {
	if d.stopChan == nil {
		panic("Discovery: discovery must be started before stopping it")
	}
	close(d.stopChan)
	d.stopWg.Wait()
	d.stopChan = nil

	logging.Logger().Info(fmt.Sprintf("Discovery: discovery is stopped"))
}

func handle(d *discovery) {
	defer d.stopWg.Done()

	for {
		select {
		case <-d.stopChan:
			return
		case data := <-d.sendChan:
			logging.Logger().Info(fmt.Sprintf("chan: %v", data))
		}
	}
}

func (d *discovery) discoverZone(dz *model.DiscoveryZone) {
	logging.Logger().Debug(fmt.Sprintf("Discovery: DiscoverZone is start"))

	doneChan := make(chan struct{})

	d.stopWg.Add(1)
	defer d.stopWg.Done()

	go scanZone(d, dz, doneChan)

	select {
	case <-d.stopChan:
		<-doneChan
	case <-doneChan:
		logging.Logger().Debug(fmt.Sprintf("Discovery: DiscoverZone is complete"))
	}
}

func (d *discovery) discoverHost(dh *model.DiscoveryHost) {
	logging.Logger().Debug(fmt.Sprintf("DiscoverHost"))
}

func (d *discovery) discoverPort(dp *model.DiscoveryPort) {
	logging.Logger().Debug(fmt.Sprintf("DiscoverPort"))
}

func (d *discovery) discoverService(ds *model.DiscoveryService) {
	logging.Logger().Debug(fmt.Sprintf("DiscoverService"))
}

func (d *discovery) sendResult() {

}

func (d *discovery) sendError() {

}