localize community and user links, regex cleanup

Makefile

@@ -11,7 +11,7 @@ reload:
 
 serve:
 	#python  -m http.server --directory ./public 8081 &>/dev/null
-	watchexec -e go -r "go run . --addr 0.0.0.0:8008 -w"
+	DEBUG=true watchexec -e go -r "go run . --addr 0.0.0.0:8008 -w"
 
 style:
 	npm run watchcss > /dev/null 2>&1

main.go

@@ -7,6 +7,7 @@ import (
 	"log"
 	"net"
 	"net/http"
+	"os"
 
 	"github.com/julienschmidt/httprouter"
 	"github.com/yuin/goldmark"
@@ -64,6 +65,40 @@ func init() {
 			templates[name] = glob
 		}
 	}
+	if os.Getenv("DEBUG") != "" {
+		test()
+	}
+}
+func test() {
+	links := [][]string{
+		[]string{"https://lemmy.local/u/dude", "/lemmy.local/u/dude", "/u/dude"},
+		[]string{"https://lemmy.local/u/dude@lemmy.local", "/lemmy.local/u/dude", "/u/dude"},
+		[]string{"/u/dude", "/lemmy.local/u/dude", "/u/dude"},
+		[]string{"https://lemmy.world/c/dude", "/lemmy.local/c/dude@lemmy.world", "/c/dude@lemmy.world"},
+		[]string{"https://lemmy.world/u/dude", "/lemmy.local/u/dude@lemmy.world", "/u/dude@lemmy.world"},
+		[]string{"https://lemmy.world/u/dude@lemmy.world", "/lemmy.local/u/dude@lemmy.world", "/u/dude@lemmy.world"},
+		[]string{"https://lemmy.world/post/123", "/lemmy.world/post/123", "https://lemmy.world/post/123"},
+		[]string{"/post/123", "/lemmy.local/post/123", "/post/123"},
+		[]string{"/comment/123", "/lemmy.local/comment/123", "/comment/123"},
+		[]string{"https://lemmy.local/comment/123", "/lemmy.local/comment/123", "/comment/123"},
+	}
+	for _, url := range links {
+		output := LemmyLinkRewrite(`href="`+url[0]+`"`, "lemmy.local", "")
+		success := (output == (`href="` + url[1] + `"`))
+		if !success {
+			fmt.Println("\n!!!! Link rewrite failure !!!!")
+			fmt.Println(url)
+			fmt.Println(output)
+			fmt.Println("")
+		}
+		output = LemmyLinkRewrite(`href="`+url[0]+`"`, ".", "lemmy.local")
+		success = (output == (`href="` + url[2] + `"`))
+		if !success {
+			fmt.Println(success, url)
+			fmt.Println(output)
+			fmt.Println("")
+		}
+	}
 }
 func middleware(n httprouter.Handle) httprouter.Handle {
 	return func(w http.ResponseWriter, r *http.Request, ps httprouter.Params) {

routes.go

@@ -32,12 +32,12 @@ var funcMap = template.FuncMap{
 		}
 		return host
 	},
-	"proxy": func(s string) string {
+	"localize": func(s string) string {
 		u, err := url.Parse(s)
 		if err != nil {
 			return s
 		}
-		return "/" + u.Host + u.Path
+		return "." + u.Path + "@" + u.Host
 	},
 	"printer": func(n any) string {
 		p := message.NewPrinter(language.English)
@@ -137,22 +137,11 @@ var funcMap = template.FuncMap{
 			fmt.Println(err)
 			return template.HTML(body)
 		}
-		converted := buf.String()
+		body = buf.String()
-		converted = strings.Replace(converted, `<img `, `<img loading="lazy" `, -1)
+		body = strings.Replace(body, `<img `, `<img loading="lazy" `, -1)
-		re = regexp.MustCompile(`!([a-zA-Z0-9]+)@([a-zA-Z0-9\.\-]+)[ $]?`)
+		body = LemmyLinkRewrite(body, host, os.Getenv("LEMMY_DOMAIN"))
-		converted = re.ReplaceAllString(converted, `<a href="https://$2/c/$1">!$1@$2</a> `)
+		body = RegReplace(body, `::: spoiler (.*?)\n([\S\s]*?):::`, "<details><summary>$1</summary>$2</details>")
-		if os.Getenv("LEMMY_DOMAIN") == "" {
+		return template.HTML(body)
-			re = regexp.MustCompile(`href="\/(c\/[a-zA-Z0-9\-]+|(post|comment)\/\d+)`)
-			converted = re.ReplaceAllString(converted, `href="https://`+host+`/$1`)
-			re := regexp.MustCompile(`href="https:\/\/([a-zA-Z0-9\.\-]+\/(c\/[a-zA-Z0-9]+|(post|comment)\/\d+))`)
-			converted = re.ReplaceAllString(converted, `href="/$1`)
-		} else {
-			re := regexp.MustCompile(`href="https:\/\/` + os.Getenv("LEMMY_DOMAIN") + `\/(c\/[a-zA-Z0-9]+|(post|comment)\/\d+)`)
-			converted = re.ReplaceAllString(converted, `href="/$1`)
-		}
-		re = regexp.MustCompile(`::: spoiler (.*?)\n([\S\s]*?):::`)
-		converted = re.ReplaceAllString(converted, "<details><summary>$1</summary>$2</details>")
-		return template.HTML(converted)
 	},
 	"rmmarkdown": func(body string) string {
 		var buf bytes.Buffer
@@ -173,6 +162,40 @@ var funcMap = template.FuncMap{
 	},
 }
 
+func LemmyLinkRewrite(input string, host string, lemmy_domain string) (body string) {
+	body = input
+	// community bangs
+	body = RegReplace(body, `!([a-zA-Z0-9]+)@([a-zA-Z0-9\.\-]+)[ $]?`, `<a href="/c/$1">!$1@$2</a> `)
+	// localize community and user links
+	body = RegReplace(body, `href="https:\/\/([a-zA-Z0-9\.\-]+)\/((c|u)\/.*?)"`, `href="/$2@$1"`)
+	// remove extra instance tag
+	body = RegReplace(body, `href="\/((c|u)\/.*@.*?)@(.*?)"`, `href="/$1"`)
+	if lemmy_domain == "" {
+		// add domain to relative links
+		body = RegReplace(body, `href="\/(c\/[a-zA-Z0-9\-]+"|(post|comment)\/\d+"|(c|u)\/(.*?)")`, `href="/`+host+`/$1`)
+		// convert links to relative
+		body = RegReplace(body, `href="https:\/\/([a-zA-Z0-9\.\-]+\/(c\/[a-zA-Z0-9]+"|(post|comment)\/\d+"|u\/(.*?)"))`, `href="/$1`)
+	} else {
+		// convert local links to relative
+		body = RegReplace(body, `href="https:\/\/`+lemmy_domain+`\/(c\/[a-zA-Z0-9]+"|(post|comment)\/\d+"|u\/(.*?)")`, `href="/$1`)
+		body = RegReplace(body, `href="(.*)@`+lemmy_domain+`"`, `href="$1"`)
+	}
+	// remove redundant instance tag
+	re := regexp.MustCompile(`href="\/([a-zA-Z0-9\.\-]+)\/(c|u)\/(.*?)@(.*?)"`)
+	matches := re.FindAllStringSubmatch(body, -1)
+	for _, match := range matches {
+		if match[1] == match[4] {
+			body = strings.Replace(body, match[0], `href="/`+strings.Join(match[1:4], "/")+`"`, -1)
+		}
+	}
+	return body
+}
+
+func RegReplace(input string, match string, replace string) string {
+	re := regexp.MustCompile(match)
+	return re.ReplaceAllString(input, replace)
+}
+
 func Initialize(Host string, r *http.Request) (State, error) {
 	state := State{
 		Host:   Host,

templates/community.html

@@ -3,11 +3,11 @@
       <input name="op" type="submit" value="{{ membership .Subscribed}}">
       <input type="hidden" name="communityid" value ="{{.Community.ID}}">
     </form>
-    <span class="title"><a href="{{proxy .Community.ActorID}}">c/{{fullcname .Community}}: {{.Community.Title}}</a></span>
+    <span class="title"><a href="{{localize .Community.ActorID}}">c/{{fullcname .Community}}: {{.Community.Title}}</a></span>
   <div class="details">
 {{ if .Community.Description.IsValid }}
     <div class="description">
-      {{markdown "poop" .Community.Description.String}}
+      {{markdown "" .Community.Description.String}}
     </div>
 {{ end }}
     <div class="gray">