Highlight @username, links and emails in descriptions; and some fixes

lib/textparsing/init.go

@@ -0,0 +1,42 @@
+package textparsing
+
+import (
+	"fmt"
+	"html"
+	"net/url"
+	"regexp"
+	"strings"
+)
+
+//var wordre = regexp.MustCompile(`\S+`)
+
+// var urlre = regexp.MustCompile(`https?:\/\/[-a-zA-Z0-9@%._\+~#=]{2,256}\.[a-z]{1,6}[-a-zA-Z0-9@:%_\+.~#?&\/\/=]*`)
+// var emailre = regexp.MustCompile(`[-a-zA-Z0-9%._\+~#=]+@[-a-zA-Z0-9%._\+~=&]{2,256}\.[a-z]{1,6}`)
+// var usernamere = regexp.MustCompile(`@[a-z0-9\-]+`)
+var theregex = regexp.MustCompile(`@[a-z0-9\-]+|(?:https?:\/\/[-a-zA-Z0-9@%._\+~#=]{2,256}\.[a-z]{1,6}[-a-zA-Z0-9@:%_\+.~#?&\/\/=]*)|(?:[-a-zA-Z0-9%._\+~#=]+@[-a-zA-Z0-9%._\+~=&]{2,256}\.[a-z]{1,6})`)
+
+func replacer(ent string) string {
+	if strings.HasPrefix(ent, "@") {
+		return fmt.Sprintf(`<a class="link" href="/%s">%s</a>`, ent[1:], ent)
+	}
+
+	if strings.HasPrefix(ent, "https://") || strings.HasPrefix(ent, "http://") {
+		ent = html.UnescapeString(ent)
+		parsed, err := url.Parse(ent)
+		if err == nil {
+			href := ent
+			if parsed.Host == "soundcloud.com" || strings.HasSuffix(parsed.Host, ".soundcloud.com") {
+				href = "/" + strings.Join(strings.Split(ent, "/")[3:], "/")
+			}
+
+			return fmt.Sprintf(`<a class="link" href="%s" referrerpolicy="no-referrer" rel="external nofollow noopener noreferrer ugc" target="_blank">%s</a>`, href, ent)
+		}
+	}
+
+	// Otherwise, it can only be an email
+	return fmt.Sprintf(`<a class="link" href="mailto:%s">%s</a>`, ent, ent)
+}
+
+func Format(text string) string {
+	return theregex.ReplaceAllStringFunc(html.EscapeString(text), replacer)
+}