fix a panic and handle cleaning up after a panic

cmd/manage/main.go

@@ -5,6 +5,7 @@ import (
 	"fmt"
 	"log"
 	"os"
+	"runtime/debug"
 	"sync"
 
 	"git.yetaga.in/alazyreader/library/book"
@@ -116,6 +117,19 @@ func main() {
 	if err != nil {
 		log.Fatalln(err)
 	}
+	// cleanup our screen and log if we panic and crash out somewhere
+	defer func() {
+		if r := recover(); r != nil {
+			if screen != nil {
+				screen.Fini()
+			}
+			fmt.Println("fatal panic;", r)
+			if c.Debug {
+				fmt.Println("stacktrace: \n" + string(debug.Stack()))
+			}
+			return
+		}
+	}()
 
 	l := ui.NewList(Titles(state.Get("library").([]book.Book)), 0)
 	menu := ui.NewBox(

config/config.go

@@ -6,4 +6,5 @@ type Config struct {
 	DBHost string
 	DBPort string
 	DBName string
+	Debug  bool
 }

ui/ui.go

@@ -296,6 +296,9 @@ func (l *List) Selected() int {
 }
 
 func (l *List) SelectedID() int {
+	if l.listItems == nil || len(l.listItems) == 0 {
+		return 0
+	}
 	return l.listItems[l.selected].Key
 }