add podcast page

main.go

@@ -357,6 +357,34 @@ func main() {
 		sendJSON(w, podcasts, 200)
 	})
 
+	mux.HandleFunc("GET /podcasts/{id}", func(w http.ResponseWriter, r *http.Request) {
+		id, err := strconv.Atoi(r.PathValue("id"))
+		if err != nil {
+			http.Error(w, err.Error(), 404)
+			return
+		}
+
+		podcast, err := getPodcastById(db, int64(id))
+		if err != nil {
+			http.Error(w, err.Error(), 404)
+			return
+		}
+
+		episodes, err := getPodcastEpisodes(db, podcast.ID)
+		if err != nil {
+			http.Error(w, err.Error(), 404)
+			return
+		}
+
+		tmpl.ExecuteTemplate(w, "podcast.html", struct {
+			Podcast  *Podcast
+			Episodes []*Episode
+		}{
+			Podcast:  podcast,
+			Episodes: episodes,
+		})
+	})
+
 	mux.HandleFunc("POST /podcasts", func(w http.ResponseWriter, r *http.Request) {
 		var body struct {
 			Feed string `json:"feed"`