1 files changed, 60 insertions, 0 deletions
diff --git a/forged/internal/web/error_pages.go b/forged/internal/web/error_pages.go
new file mode 100644
index 0000000..2ba9a1a
--- /dev/null
+++ b/forged/internal/web/error_pages.go
@@ -0,0 +1,60 @@
+// SPDX-License-Identifier: AGPL-3.0-only
+// SPDX-FileCopyrightText: Copyright (c) 2025 Runxi Yu <https://runxiyu.org>
+
+package web
+
+import (
+	"html/template"
+	"net/http"
+)
+
+// ErrorPage404 renders a 404 Not Found error page using the "404" template.
+func ErrorPage404(templates *template.Template, w http.ResponseWriter, params map[string]any) {
+	w.WriteHeader(http.StatusNotFound)
+	_ = templates.ExecuteTemplate(w, "404", params)
+}
+
+// ErrorPage400 renders a 400 Bad Request error page using the "400" template.
+// The error message is passed via the "complete_error_msg" template param.
+func ErrorPage400(templates *template.Template, w http.ResponseWriter, params map[string]any, msg string) {
+	w.WriteHeader(http.StatusBadRequest)
+	params["complete_error_msg"] = msg
+	_ = templates.ExecuteTemplate(w, "400", params)
+}
+
+// ErrorPage400Colon renders a 400 Bad Request error page telling the user
+// that we migrated from : to -.
+func ErrorPage400Colon(templates *template.Template, w http.ResponseWriter, params map[string]any) {
+	w.WriteHeader(http.StatusBadRequest)
+	_ = templates.ExecuteTemplate(w, "400_colon", params)
+}
+
+// ErrorPage403 renders a 403 Forbidden error page using the "403" template.
+// The error message is passed via the "complete_error_msg" template param.
+func ErrorPage403(templates *template.Template, w http.ResponseWriter, params map[string]any, msg string) {
+	w.WriteHeader(http.StatusForbidden)
+	params["complete_error_msg"] = msg
+	_ = templates.ExecuteTemplate(w, "403", params)
+}
+
+// ErrorPage451 renders a 451 Unavailable For Legal Reasons error page using the "451" template.
+// The error message is passed via the "complete_error_msg" template param.
+func ErrorPage451(templates *template.Template, w http.ResponseWriter, params map[string]any, msg string) {
+	w.WriteHeader(http.StatusUnavailableForLegalReasons)
+	params["complete_error_msg"] = msg
+	_ = templates.ExecuteTemplate(w, "451", params)
+}
+
+// ErrorPage500 renders a 500 Internal Server Error page using the "500" template.
+// The error message is passed via the "complete_error_msg" template param.
+func ErrorPage500(templates *template.Template, w http.ResponseWriter, params map[string]any, msg string) {
+	w.WriteHeader(http.StatusInternalServerError)
+	params["complete_error_msg"] = msg
+	_ = templates.ExecuteTemplate(w, "500", params)
+}
+
+// ErrorPage501 renders a 501 Not Implemented error page using the "501" template.
+func ErrorPage501(templates *template.Template, w http.ResponseWriter, params map[string]any) {
+	w.WriteHeader(http.StatusNotImplemented)
+	_ = templates.ExecuteTemplate(w, "501", params)
+}