From 586b293bef75233e4607d28b8e0d0db4f8c6b36d Mon Sep 17 00:00:00 2001
From: Aaron Fischer <mail@aaron-fischer.net>
Date: Wed, 9 Jun 2021 01:19:26 +0200
Subject: [PATCH] Convert images to images instead of links

Image links will result in a `img` tag instead of a `a` tag. This
behaviour is disabled by default and can be enabled by adding the
following line to to config file:

convertimages: true

To get access to the config in the convert file, I had to move the
config file inside the gmitohtml namespace. This is specially handy
later on if the config file contains other settings which are useful for
the rest of the codebase.
---
 config.go                |  7 ++++++-
 main.go                  | 12 ++++++------
 pkg/gmitohtml/convert.go | 33 +++++++++++++++++++++++++++------
 3 files changed, 39 insertions(+), 13 deletions(-)

diff --git a/config.go b/config.go
index ab9104b..aa8ca70 100644
--- a/config.go
+++ b/config.go
@@ -1,4 +1,4 @@
-package main
+package gmitohtml
 
 import (
 	"crypto/tls"
@@ -22,12 +22,17 @@ type certConfig struct {
 type appConfig struct {
 	Bookmarks map[string]string
 
+	// Convert image links to images instead of normal links
+	ConvertImages bool
+
 	Certs map[string]*certConfig
 }
 
 var config = &appConfig{
 	Bookmarks: make(map[string]string),
 
+	ConvertImages: false,
+
 	Certs: make(map[string]*certConfig),
 }
 
diff --git a/main.go b/main.go
index 1b3685f..191a634 100644
--- a/main.go
+++ b/main.go
@@ -46,7 +46,7 @@ func main() {
 	// TODO option to include response header in page
 	flag.Parse()
 
-	defaultConfig := defaultConfigPath()
+	defaultConfig := gmitohtml.DefaultConfigPath()
 	if configFile == "" {
 		configFile = defaultConfig
 	}
@@ -58,18 +58,18 @@ func main() {
 		}
 
 		if configExists || configFile != defaultConfig {
-			err := readconfig(configFile)
+			err := gmitohtml.ReadConfig(configFile)
 			if err != nil {
 				log.Fatalf("failed to read configuration file at %s: %v\nSee CONFIGURATION.md for information on configuring gmitohtml", configFile, err)
 			}
 
-			for u, label := range config.Bookmarks {
+			for u, label := range gmitohtml.Config.Bookmarks {
 				gmitohtml.AddBookmark(u, label)
 			}
 		}
 	}
 
-	for domain, cc := range config.Certs {
+	for domain, cc := range gmitohtml.Config.Certs {
 		certData, err := ioutil.ReadFile(cc.Cert)
 		if err != nil {
 			log.Fatalf("failed to load client certificate for domain %s: %s", domain, err)
@@ -88,9 +88,9 @@ func main() {
 
 	if daemon != "" {
 		gmitohtml.SetOnBookmarksChanged(func() {
-			config.Bookmarks = gmitohtml.GetBookmarks()
+			gmitohtml.Config.Bookmarks = gmitohtml.GetBookmarks()
 
-			err := saveConfig(configFile)
+			err := gmitohtml.SaveConfig(configFile)
 			if err != nil {
 				log.Fatal(err)
 			}
diff --git a/pkg/gmitohtml/convert.go b/pkg/gmitohtml/convert.go
index 549df8e..59588be 100644
--- a/pkg/gmitohtml/convert.go
+++ b/pkg/gmitohtml/convert.go
@@ -19,6 +19,8 @@ var daemonAddress string
 
 var assetLock sync.Mutex
 
+var imageExtensions = []string{"png", "jpg", "jpeg", "gif", "svg", "webp"}
+
 func rewriteURL(u string, loc *url.URL) string {
 	if daemonAddress != "" {
 		scheme := "gemini"
@@ -126,12 +128,31 @@ func Convert(page []byte, u string) []byte {
 				linkLabel = line[splitStart:]
 			}
 
-			link := append([]byte(`<a href="`), html.EscapeString(rewriteURL(string(linkURL), parsedURL))...)
-			link = append(link, []byte(`">`)...)
-			link = append(link, html.EscapeString(string(linkLabel))...)
-			link = append(link, []byte(`</a>`)...)
-			result = append(result, link...)
-			result = append(result, []byte("<br>")...)
+			// If link ends with gif/png/jpg, add a image instead of a link
+			parts := strings.Split(string(linkURL), ".")
+			extension := parts[len(parts)-1]
+			isImage := false
+			for _, ext := range imageExtensions {
+				if extension == ext {
+					isImage = true
+				}
+			}
+
+			if isImage && Config.ConvertImages {
+				img := append([]byte(`<img src="`), html.EscapeString(rewriteURL(string(linkURL), parsedURL))...)
+				img = append(img, []byte(`" alt="`)...)
+				img = append(img, html.EscapeString(string(linkLabel))...)
+				img = append(img, []byte(`"/>`)...)
+				result = append(result, img...)
+			} else {
+				link := append([]byte(`<a href="`), html.EscapeString(rewriteURL(string(linkURL), parsedURL))...)
+				link = append(link, []byte(`">`)...)
+				link = append(link, html.EscapeString(string(linkLabel))...)
+				link = append(link, []byte(`</a>`)...)
+				result = append(result, link...)
+			    result = append(result, []byte("<br>")...)
+			}
+
 			continue
 		}