package main

import (
	"context"
	"errors"
	"log"
	"sync"
	"time"

	"git.joco.dk/sng/fermentord/pkg/daemon"
	"github.com/getsentry/sentry-go"
	"github.com/jackc/pgx/v4"
	"github.com/jackc/pgx/v4/pgxpool"
	"github.com/nats-io/nats.go"
)

func serve(ctx context.Context, wg *sync.WaitGroup, sub *nats.Subscription, db *pgxpool.Pool) {
	hub := sentry.CurrentHub().Clone()
	defer wg.Done()

	for {
		m, err := sub.NextMsgWithContext(ctx)
		if errors.Is(err, nats.ErrInvalidContext) {
			return
		}
		if errors.Is(err, nats.ErrBadSubscription) {
			hub.CaptureException(err)
			log.Fatal(err)
		}
		if errors.Is(err, nats.ErrConnectionClosed) {
			hub.CaptureException(err)
			time.Sleep(10 * time.Second)
			continue
		}
		if errors.Is(err, nats.ErrTimeout) {
			hub.CaptureException(err)
			log.Print(err)
			continue
		}
		if err != nil {
			hub.CaptureException(err)
			log.Fatal(err)
		}

		err = db.BeginFunc(ctx, func(tx pgx.Tx) error {
			switch m.Subject {
			case "state":
				q := "INSERT INTO fermentor.state (c_time, state) VALUES ($1, $2)"
				// TODO Unmarshal JSON.
				if _, err := tx.Query(ctx, q, ); err != nil {
					return err
				}

			case "temp":
				q := "INSERT INTO fermentor.temperature_reading (c_time, sensor, millis) VALUES ($1, $2, $3)"
				// TODO Unmarshal JSON.
				if _, err := tx.Query(ctx, q); err != nil {
					return err
				}
			}

			if err := tx.Commit(ctx); err != nil {
				return err
			}

			return nil
		})
		if err != nil {
			hub.CaptureException(err)
			log.Print(err)
			continue
		}

		if err := m.AckSync(); err != nil {
			hub.CaptureException(err)
			log.Print(err)
			continue
		}
	}
}

func main() {
	// Sentry
	err := sentry.Init(sentry.ClientOptions{
		Dsn:              "https://7278625538334140991ce433e0ad292f@sentry.joco.dk/24",
		TracesSampleRate: 1.0,
	})
	if err != nil {
		log.Fatal(err)
	}
	defer sentry.Flush(10 * time.Second)

	// NATS
	nc, err := nats.Connect("nats://nats.service.consul")
	if err != nil {
		log.Fatal(err)
	}

	js, err := nc.JetStream(nats.PublishAsyncMaxPending(256))
	if err != nil {
		log.Fatal(err)
	}

	sub, err := js.SubscribeSync("FERMENTOR.*", nats.Durable("filer"))
	if err != nil {
		log.Fatal(err)
	}

	ctx, shutdown := context.WithCancel(context.Background())
	wg := &sync.WaitGroup{}

	db, err := pgxpool.Connect(ctx, "pgdb1.service.s18.consul")
	if err != nil {
		log.Fatal(err)
	}

	wg.Add(1)
	log.Print("Ready")
	go serve(ctx, wg, sub, db)
	daemon.WaitForSignalsDefault()

	log.Print("Shutting down")
	shutdown()
	log.Print("Shutdown complete")

}