fixing comment keying, fixing comment storage location

comments/comments.go

@@ -8,6 +8,7 @@ import (
 	"html/template"
 	"io"
 	"net/http"
+	"strconv"
 	"sync"
 	"time"
 
@@ -175,17 +176,27 @@ func (d *diskvStorage) nextKey(post string) (string, error) {
 	d.keyMtx.Lock()
 	defer d.keyMtx.Unlock()
 
-	var i uint64
-
 	prefix := post + "-"
 
+	lastKey := prefix
+
 	keys := d.KeysPrefix(prefix, nil)
-	for range keys {
-		i++
+	for key := range keys {
+		lastKey = key
 	}
 
-	key := prefix + fmt.Sprint(i)
-	err := d.WriteStream(key, &bytes.Buffer{}, true)
+	if lastKey == prefix {
+		return prefix + "1", nil
+	}
+
+	minusPrefix := lastKey[len(prefix):]
+	lastIdx, err := strconv.Atoi(minusPrefix)
+	if err != nil {
+		return "", fmt.Errorf("comment key %q seems malformed", lastKey)
+	}
+
+	key := prefix + fmt.Sprint(lastIdx+1)
+	err = d.WriteStream(key, &bytes.Buffer{}, true)
 
 	return key, err
 }