package main

import (
	"log/slog"
	"math/rand/v2"
	"os"
	"path"
	"time"

	"github.com/fsnotify/fsnotify"
	"gopkg.in/yaml.v3"
)

type InputDb map[int]string

func newInputDbFromFile(path string, db *InputDb) {
	file, err := os.ReadFile(path)
	if err != nil {
		slog.Error("Could not open file", "path", path)
		os.Exit(1)
	}
	err = yaml.Unmarshal(file, &db)
	if err != nil {
		slog.Error("Error unmarshaling", "path", path, "error", err)
	} else {
		slog.Info("Reloaded Input", "path", path)
	}
}

func (db InputDb) Lookup(key int) string {
	value, ok := db[key]
	if !ok {
		return "X"
	}
	return value
}

func main() {
	var db InputDb
	done := make(chan struct{}, 1)
	ticker := time.NewTicker(100 * time.Millisecond)

	watcher, err := fsnotify.NewWatcher()
	if err != nil {
		slog.Error("Could not create Watcher", "error", err)
	}
	defer watcher.Close()
	newInputDbFromFile("input/input.yml", &db)
	slog.Info("Loaded DB", "db", db)

	err = watcher.Add("input/")
	if err != nil {
		slog.Error("Could not watch path", "path", "input/")
	}

	go func() {
		for {
			select {
			case t := <-ticker.C:
				key := rand.IntN(9) + 1
				value := db.Lookup(key)
				slog.Info("Got Rand", "key", key, "value", value, "ticker", t)
			case event := <-watcher.Events:
				if event.Has(fsnotify.Write) && event.Name == "input/input.yml" {
					slog.Info("Got Event", "event.name", event.Name, "event.name.base", path.Base(event.Name), "event.name.dir", path.Dir(event.Name), "event.op", event.Op, "watchlist", watcher.WatchList())
					newInputDbFromFile("input/input.yml", &db)
				}
			case err := <-watcher.Errors:
				slog.Error("Could not watch", "error", err)
			}
		}
	}()

	<-done
}