1 files changed, 40 insertions, 4 deletions
diff --git a/src/gmi/tpl.go b/src/gmi/tpl.go
index 7aa1a2f..7959b8e 100644
--- a/src/gmi/tpl.go
+++ b/src/gmi/tpl.go
@@ -25,6 +25,11 @@ type rendererGetPostsRes struct {
 	HasMore bool
 }
 
+type rendererGetPostSeriesNextPreviousRes struct {
+	Next     *post.StoredPost
+	Previous *post.StoredPost
+}
+
 type renderer struct {
 	url       *url.URL
 	postStore post.Store
@@ -43,6 +48,41 @@ func (r renderer) GetPostByID(id string) (post.StoredPost, error) {
 	return p, nil
 }
 
+func (r renderer) GetPostSeriesNextPrevious(p post.StoredPost) (rendererGetPostSeriesNextPreviousRes, error) {
+
+	seriesPosts, err := r.postStore.GetBySeries(p.Series)
+	if err != nil {
+		return rendererGetPostSeriesNextPreviousRes{}, fmt.Errorf(
+			"fetching posts for series %q: %w", p.Series, err,
+		)
+	}
+
+	var (
+		res       rendererGetPostSeriesNextPreviousRes
+		foundThis bool
+	)
+
+	for i := range seriesPosts {
+
+		seriesPost := seriesPosts[i]
+
+		if seriesPost.ID == p.ID {
+			foundThis = true
+			continue
+		}
+
+		if !foundThis {
+			res.Next = &seriesPost
+			continue
+		}
+
+		res.Previous = &seriesPost
+		break
+	}
+
+	return res, nil
+}
+
 func (r renderer) GetQueryValue(key, def string) string {
 	v := r.url.Query().Get(key)
 	if v == "" {
@@ -97,10 +137,6 @@ func (a *api) tplHandler() (gemini.Handler, error) {
 		r *gemini.Request,
 	) {
 
-		if strings.HasSuffix(r.URL.Path, "/") {
-			r.URL.Path += "index.gmi"
-		}
-
 		tplPath := strings.TrimPrefix(r.URL.Path, "/")
 
 		ctx = mctx.Annotate(ctx,