From 7aab65f2ac5e055990887326bc7c6f6dd45e78ec Mon Sep 17 00:00:00 2001
From: Wim Brand <fornax@fornaxian.com>
Date: Sat, 6 Jul 2019 19:36:04 +0200
Subject: [PATCH] Better metadata

---
 res/template/file_viewer.html  |  13 +----
 webcontroller/file_viewer.go   |   2 +-
 webcontroller/list_viewer.go   |   2 +-
 webcontroller/opengraph.go     | 103 ++++++++++++++++++++++++---------
 webcontroller/template_data.go |   2 +-
 5 files changed, 80 insertions(+), 42 deletions(-)

diff --git a/res/template/file_viewer.html b/res/template/file_viewer.html
index 2053321..e8bdf8d 100644
--- a/res/template/file_viewer.html
+++ b/res/template/file_viewer.html
@@ -16,18 +16,7 @@
 
 		{{template "bgpattern"}}
 
-		<meta name="theme-color"        content="#202020"/>
-		<meta name="twitter:image"      content="{{.OGData.Image}}" />
-		<meta property="og:title"       content="{{.OGData.Title}}" />
-		<meta property="og:type"        content="{{.OGData.Type}}" />
-		<meta property="og:site_name"   content="{{.OGData.SiteName}}" />
-		<meta property="og:description" content="{{.OGData.Description}}" />
-		<meta property="description"    content="{{.OGData.Description}}" />
-		<meta property="og:url"         content="{{.OGData.URL}}" />
-		<meta property="og:image"       content="{{.OGData.Image}}" />
-		<meta property="og:image:url"   content="{{.OGData.Image}}" />
-		<meta property="article:author" content="Fornax96" />
-		<link rel="image_src"              href="{{.OGData.Image}}" />
+		{{.OGData}}
 
 		<script type="text/javascript">
 			var apiEndpoint = '{{.APIEndpoint}}';
diff --git a/webcontroller/file_viewer.go b/webcontroller/file_viewer.go
index 7c9b848..0de4518 100644
--- a/webcontroller/file_viewer.go
+++ b/webcontroller/file_viewer.go
@@ -48,7 +48,7 @@ func (wc *WebController) serveFileViewer(w http.ResponseWriter, r *http.Request,
 	}
 
 	templateData := wc.newTemplateData(w, r)
-	templateData.OGData = OpenGraphFromFile(*finfo[0])
+	templateData.OGData = metadataFromFile(*finfo[0])
 	var err error
 	if list {
 		templateData.Title = fmt.Sprintf("%d files in Pixeldrain", len(finfo))
diff --git a/webcontroller/list_viewer.go b/webcontroller/list_viewer.go
index 330bb5f..9cd8d10 100644
--- a/webcontroller/list_viewer.go
+++ b/webcontroller/list_viewer.go
@@ -24,7 +24,7 @@ func (wc *WebController) serveListViewer(w http.ResponseWriter, r *http.Request,
 
 	var templateData = wc.newTemplateData(w, r)
 	templateData.Title = fmt.Sprintf("%s ~ Pixeldrain list", list.Title)
-	templateData.OGData = OpenGraphFromList(*list)
+	templateData.OGData = metadataFromList(*list)
 	templateData.Other = viewerData{
 		Type:       "list",
 		CaptchaKey: wc.captchaSiteKey,
diff --git a/webcontroller/opengraph.go b/webcontroller/opengraph.go
index c0f7127..69b33e1 100644
--- a/webcontroller/opengraph.go
+++ b/webcontroller/opengraph.go
@@ -1,38 +1,87 @@
 package webcontroller
 
 import (
+	"html/template"
+	"strings"
+
 	"fornaxian.com/pixeldrain-web/pixelapi"
 )
 
-// OGData holds all information needed to populate the various meta tags on the
-// file and list viewer
-type OGData struct {
-	Title       string
-	Type        string
-	SiteName    string
-	Description string
-	URL         string
-	Image       string
+type ogRule struct {
+	Prop    string
+	Content string
 }
 
-// OpenGraphFromFile populates the OGData object from FileInfo
-func OpenGraphFromFile(f pixelapi.FileInfo) (og OGData) {
-	og.Title = f.Name
-	og.Type = "website"
-	og.SiteName = "Pixeldrain"
-	og.Description = "View " + f.Name + " on Pixeldrain"
-	og.URL = "/u/" + f.ID
-	og.Image = "/api/file/" + f.ID + "/thumbnail"
-	return og
+func (o ogRule) HTML() template.HTML {
+	return template.HTML(`<meta property="` + o.Prop + `" content="` + o.Content + `"/>` + "\n")
 }
 
-// OpenGraphFromList populates the OGData object from a List
-func OpenGraphFromList(l pixelapi.List) (og OGData) {
-	og.Title = l.Title
-	og.Type = "website"
-	og.SiteName = "Pixeldrain"
-	og.Description = "View " + l.Title + " on Pixeldrain"
-	og.URL = "/l/" + l.ID
-	og.Image = "/api/file/" + l.Files[0].ID + "/thumbnail"
-	return og
+type twitterRule struct {
+	Name    string
+	Content string
+}
+
+func (o twitterRule) HTML() template.HTML {
+	return template.HTML(`<meta name="` + o.Name + `" content="` + o.Content + `"/>` + "\n")
+}
+
+type linkRule struct {
+	Rel  string
+	HREF string
+}
+
+func (o linkRule) HTML() template.HTML {
+	return template.HTML(`<link name="` + o.Rel + `" href="` + o.HREF + `"/>` + "\n")
+}
+
+func metadataFromFile(f pixelapi.FileInfo) (meta template.HTML) {
+	meta += ogRule{"og:title", f.Name}.HTML()
+	meta += ogRule{"og:site_name", "pixeldrain"}.HTML()
+	meta += ogRule{"og:description", "View '" + f.Name + "' on Pixeldrain"}.HTML()
+	meta += ogRule{"description", "View '" + f.Name + "' on Pixeldrain"}.HTML()
+	meta += ogRule{"og:url", "/u/" + f.ID}.HTML()
+
+	if strings.HasPrefix(f.MimeType, "image") {
+		meta += ogRule{"og:type", "article"}.HTML()
+		meta += ogRule{"og:image", "/api/file/" + f.ID}.HTML()
+
+		meta += twitterRule{"twitter:image", "/api/file/" + f.ID}.HTML()
+		meta += linkRule{"image_src", "/api/file/" + f.ID}.HTML()
+	} else if strings.HasPrefix(f.MimeType, "video") {
+		meta += ogRule{"og:type", "video.other"}.HTML()
+		meta += ogRule{"og:image", "/api/file/" + f.ID + "/thumbnail"}.HTML()
+		meta += ogRule{"og:video", "/api/file/" + f.ID}.HTML()
+		meta += ogRule{"og:video:secure_url", "/api/file/" + f.ID}.HTML()
+		meta += ogRule{"og:video:type", f.MimeType}.HTML()
+
+		meta += twitterRule{"twitter:card", "player"}.HTML()
+		meta += twitterRule{"twitter:image", "/api/file/" + f.ID + "/thumbnail"}.HTML()
+		meta += twitterRule{"twitter:player", "/api/file/" + f.ID}.HTML()
+		meta += twitterRule{"twitter:player:stream", "/api/file/" + f.ID}.HTML()
+		meta += twitterRule{"twitter:player:stream:content_type", f.MimeType}.HTML()
+		meta += linkRule{"image_src", "/api/file/" + f.ID + "/thumbnail"}.HTML()
+	} else if strings.HasPrefix(f.MimeType, "audio") {
+		meta += ogRule{"og:type", "music.song"}.HTML()
+		meta += ogRule{"og:audio", "/api/file/" + f.ID}.HTML()
+		meta += ogRule{"og:audio:secure_url", "/api/file/" + f.ID}.HTML()
+		meta += ogRule{"og:audio:type", f.MimeType}.HTML()
+		meta += linkRule{"image_src", "/api/file/" + f.ID + "/thumbnail"}.HTML()
+	} else {
+		meta += ogRule{"og:type", "website"}.HTML()
+		meta += linkRule{"image_src", "/api/file/" + f.ID + "/thumbnail"}.HTML()
+	}
+	return meta
+}
+func metadataFromList(l pixelapi.List) (meta template.HTML) {
+	meta += ogRule{"og:type", "website"}.HTML()
+	meta += ogRule{"og:title", l.Title}.HTML()
+	meta += ogRule{"og:site_name", "pixeldrain"}.HTML()
+	meta += ogRule{"og:description", "View '" + l.Title + "' on Pixeldrain"}.HTML()
+	meta += ogRule{"description", "View '" + l.Title + "' on Pixeldrain"}.HTML()
+	meta += ogRule{"og:url", "/l/" + l.ID}.HTML()
+	meta += ogRule{"og:image", "/api/file/" + l.Files[0].ID + "/thumbnail"}.HTML()
+	meta += ogRule{"og:image:url", "/api/file/" + l.Files[0].ID + "/thumbnail"}.HTML()
+	meta += twitterRule{"twitter:image", "/api/file/" + l.Files[0].ID + "/thumbnail"}.HTML()
+	meta += linkRule{"image_src", "/api/file/" + l.Files[0].ID + "/thumbnail"}.HTML()
+	return meta
 }
diff --git a/webcontroller/template_data.go b/webcontroller/template_data.go
index d4c3596..5b088bc 100644
--- a/webcontroller/template_data.go
+++ b/webcontroller/template_data.go
@@ -23,7 +23,7 @@ type TemplateData struct {
 
 	// Only used on file viewer page
 	Title  string
-	OGData OGData
+	OGData template.HTML
 
 	Other    interface{}
 	URLQuery url.Values