initial code (#6)

* initial code commit

rss/rss.go

@@ -0,0 +1,62 @@
+package rss
+
+import (
+	"github.com/l3uddz/nabarr/cache"
+	"github.com/l3uddz/nabarr/cmd/nabarr/pvr"
+	"github.com/l3uddz/nabarr/logger"
+	"github.com/lefelys/state"
+	"github.com/robfig/cron/v3"
+	"github.com/rs/zerolog"
+	"time"
+)
+
+type Client struct {
+	cron             *cron.Cron
+	cache            *cache.Client
+	cacheFiltersHash string
+	pvrs             map[string]pvr.PVR
+
+	log zerolog.Logger
+}
+
+func New(c Config, cc *cache.Client, cfh string, pvrs map[string]pvr.PVR) *Client {
+	return &Client{
+		cron: cron.New(cron.WithChain(
+			cron.Recover(cron.DefaultLogger),
+		)),
+		cache:            cc,
+		cacheFiltersHash: cfh,
+		pvrs:             pvrs,
+
+		log: logger.New(c.Verbosity).With().Logger(),
+	}
+}
+
+func (c *Client) Start() state.State {
+	c.cron.Start()
+
+	st, tail := state.WithShutdown()
+	ticker := time.NewTicker(1 * time.Second)
+
+	go func() {
+		for {
+			select {
+			case <-tail.End():
+				ticker.Stop()
+
+				// shutdown cron
+				ctx := c.cron.Stop()
+				select {
+				case <-ctx.Done():
+				case <-time.After(5 * time.Second):
+				}
+
+				tail.Done()
+				return
+			case <-ticker.C:
+			}
+		}
+	}()
+
+	return st
+}