From 8012691d7a4838e77d3b8996fd0ed5e447355d57 Mon Sep 17 00:00:00 2001
From: Jan-Lukas Else <mail@jlelse.de>
Date: Tue, 27 Dec 2022 08:29:32 +0100
Subject: [PATCH] Use fallback title generated from summary in HTML HEAD title

---
 microformats.go | 8 ++------
 postsFuncs.go   | 4 ++++
 ui.go           | 6 +++++-
 utils.go        | 7 +++++++
 4 files changed, 18 insertions(+), 7 deletions(-)

diff --git a/microformats.go b/microformats.go
index 3075910..4ee4c59 100644
--- a/microformats.go
+++ b/microformats.go
@@ -86,12 +86,8 @@ func parseMicroformatsFromReader(u string, r io.Reader) (*microformatsResult, er
 		m.Title = ""
 	}
 	// Shorten content and title if too long
-	if cr := []rune(m.Content); len(cr) > 500 {
-		m.Content = string(cr[0:497]) + "…"
-	}
-	if tr := []rune(m.Title); len(tr) > 60 {
-		m.Title = string(tr[0:57]) + "…"
-	}
+	m.Content = truncateStringWithEllipsis(m.Content, 500)
+	m.Title = truncateStringWithEllipsis(m.Title, 60)
 	return m, nil
 }
 
diff --git a/postsFuncs.go b/postsFuncs.go
index ee29813..64a0def 100644
--- a/postsFuncs.go
+++ b/postsFuncs.go
@@ -128,6 +128,10 @@ func (a *goBlog) postSummary(p *post) (summary string) {
 	return
 }
 
+func (a *goBlog) fallbackTitle(p *post) string {
+	return truncateStringWithEllipsis(a.postSummary(p), 30)
+}
+
 func (a *goBlog) postTranslations(p *post) []*post {
 	translationkey := p.firstParameter("translationkey")
 	if translationkey == "" {
diff --git a/ui.go b/ui.go
index 890fbfb..9f2e2bd 100644
--- a/ui.go
+++ b/ui.go
@@ -887,7 +887,11 @@ func (a *goBlog) renderPost(hb *htmlbuilder.HtmlBuilder, rd *renderData) {
 	a.renderBase(
 		hb, rd,
 		func(hb *htmlbuilder.HtmlBuilder) {
-			a.renderTitleTag(hb, rd.Blog, p.RenderedTitle)
+			if p.RenderedTitle != "" {
+				a.renderTitleTag(hb, rd.Blog, p.RenderedTitle)
+			} else {
+				a.renderTitleTag(hb, rd.Blog, a.fallbackTitle(p))
+			}
 			hb.WriteElementOpen("link", "rel", "stylesheet", "href", a.assetFileName("css/chroma.css"))
 			a.renderPostHeadMeta(hb, p)
 			if su := a.shortPostURL(p); su != "" {
diff --git a/utils.go b/utils.go
index d0b20c5..aab6099 100644
--- a/utils.go
+++ b/utils.go
@@ -403,3 +403,10 @@ func stringToInt(s string) int {
 func loStringNotEmpty(s string, _ int) bool {
 	return s != ""
 }
+
+func truncateStringWithEllipsis(s string, l int) string {
+	if tr := []rune(s); len(tr) > l && l > 3 {
+		return string(tr[0:l-3]) + "…"
+	}
+	return s
+}