package main

import (
	"bytes"
	"encoding/json"
	"fmt"
	"io/ioutil"
	"local/storage"
	"local/truckstop/broker"
	"local/truckstop/config"
	"local/truckstop/message"
	"log"
	"regexp"
	"sort"
	"strings"
	"sync"
	"time"
)

var stateFinder = regexp.MustCompile(`[A-Za-z]+`)

func main() {
	lock := &sync.Mutex{}
	go func() {
		for {
			time.Sleep(config.Get().Interval.Email.Get())
			if err := config.Refresh(); err != nil {
				log.Println(err)
			} else {
				if config.Get().EmailerEnabled {
					lock.Lock()
					if err := email(); err != nil {
						log.Print(err)
					}
					lock.Unlock()
				}
				if config.Get().Message.Matrix.ReceiveEnabled {
					lock.Lock()
					if err := matrixrecv(); err != nil {
						log.Print(err)
					}
					lock.Unlock()
				}
			}
		}
	}()
	if err := _main(); err != nil {
		panic(err)
	}
	lock.Lock()
}

func matrixrecv() error {
	log.Printf("checking matrix...")
	defer log.Printf("/checking matrix...")
	sender := message.NewMatrix()
	messages, err := sender.Receive()
	if err != nil {
		return err
	}
	states := map[config.State]struct{}{}
	for _, msg := range messages {
		if len(states) > 0 {
			continue
		}
		for _, state := range parseOutStates([]byte(msg)) {
			states[state] = struct{}{}
		}
	}
	setNewStates(states)
	return nil
}

func setNewStates(states map[config.State]struct{}) {
	if len(states) == 0 {
		return
	}
	newstates := []config.State{}
	for k := range states {
		newstates = append(newstates, k)
	}
	sort.Slice(newstates, func(i, j int) bool {
		return newstates[i] < newstates[j]
	})
	conf := *config.Get()
	if fmt.Sprint(newstates) == fmt.Sprint(conf.States) {
		return
	}
	conf.States = newstates
	log.Printf("updating config new states: %+v", conf)
	config.Set(conf)
}

func email() error {
	log.Printf("checking email...")
	ch, err := config.Get().Emailer.ReadIMAP()
	if err != nil {
		ch, err = config.Get().Emailer.ReadIMAP()
	}
	if err != nil {
		return err
	}
	states := map[config.State]struct{}{}
	for email := range ch {
		if len(states) > 0 {
			continue
		}
		if !strings.Contains(email.Header.Get("From"), config.Get().Client) {
			continue
		}
		b, _ := ioutil.ReadAll(email.Body)
		for _, state := range parseOutStates(b) {
			states[state] = struct{}{}
		}
	}
	setNewStates(states)
	return nil
}

func parseOutStates(b []byte) []config.State {
	var states []config.State
	var state config.State
	candidates := stateFinder.FindAll(b, -1)
	for _, candidate := range candidates {
		if len(candidate) != 2 {
			continue
		}
		s := fmt.Sprintf(`"%s"`, bytes.ToUpper(candidate))
		err := json.Unmarshal([]byte(s), &state)
		if err != nil {
		} else {
			states = append(states, state)
		}
	}
	return states
}

func _main() error {
	for {
		err := _mainOne()
		if err != nil {
			log.Println(err)
		}
		if config.Get().Once {
			return err
		}
		if err != nil {
			time.Sleep(config.Get().Interval.Error.Get())
		} else {
			time.Sleep(config.Get().Interval.OK.Get())
		}
	}
	return nil
}

func _mainOne() error {
	log.Println("config.refreshing...")
	if err := config.Refresh(); err != nil {
		return err
	}
	log.Println("once...")
	if err := once(); err != nil {
		return err
	}
	log.Println("/_mainOne")
	return nil
}

func once() error {
	alljobs, err := getJobs()
	if err != nil {
		return err
	}
	newjobs, err := dropStaleJobs(alljobs)
	if err != nil {
		return err
	}
	jobs, err := dropBanlistJobs(newjobs)
	if err != nil {
		return err
	}
	for i := range jobs {
		if err := sendJob(jobs[i]); err != nil {
			return err
		}
		log.Println("sent job", jobs[i])
		if err := config.Get().DB().Set(jobs[i].ID, []byte(`sent`)); err != nil {
			return err
		}
	}
	return nil
}

func getJobs() ([]broker.Job, error) {
	states := config.Get().States
	ntg := broker.NewNTGVision()
	if config.Get().Brokers.NTG.Mock {
		ntg = ntg.WithMock()
	}
	brokers := []broker.Broker{ntg}
	jobs := []broker.Job{}
	for _, broker := range brokers {
		somejobs, err := broker.Search(states)
		if err != nil {
			return nil, err
		}
		jobs = append(jobs, somejobs...)
	}
	return jobs, nil
}

func dropStaleJobs(jobs []broker.Job) ([]broker.Job, error) {
	db := config.Get().DB()
	for i := len(jobs) - 1; i >= 0; i-- {
		if _, err := db.Get(jobs[i].ID); err == storage.ErrNotFound {
		} else if err != nil {
			return nil, err
		} else {
			jobs = append(jobs[:i], jobs[i+1:]...)
		}
	}
	return jobs, nil
}

func dropBanlistJobs(jobs []broker.Job) ([]broker.Job, error) {
	// TODO
	return jobs, nil
}

func sendJob(job broker.Job) error {
	sender := message.NewMatrix()
	return sender.Send(job.FormatMultilineText())
}