1 files changed, 84 insertions, 0 deletions
diff --git a/packages/merchant-backoffice-ui/src/settings.ts b/packages/merchant-backoffice-ui/src/settings.ts
new file mode 100644
index 000000000..0e377bec2
--- /dev/null
+++ b/packages/merchant-backoffice-ui/src/settings.ts
@@ -0,0 +1,84 @@
+/*
+ This file is part of GNU Taler
+ (C) 2021-2024 Taler Systems S.A.
+
+ GNU Taler is free software; you can redistribute it and/or modify it under the
+ terms of the GNU General Public License as published by the Free Software
+ Foundation; either version 3, or (at your option) any later version.
+
+ GNU Taler is distributed in the hope that it will be useful, but WITHOUT ANY
+ WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR
+ A PARTICULAR PURPOSE.  See the GNU General Public License for more details.
+
+ You should have received a copy of the GNU General Public License along with
+ GNU Taler; see the file COPYING.  If not, see <http://www.gnu.org/licenses/>
+ */
+
+import {
+  Codec,
+  buildCodecForObject,
+  canonicalizeBaseUrl,
+  codecForString,
+  codecOptional
+} from "@gnu-taler/taler-util";
+
+export interface MerchantUiSettings {
+  // Where merchant backend is localted
+  // default: window.origin without "webui/"
+  backendBaseURL?: string;
+}
+
+/**
+ * Global settings for the bank UI.
+ */
+const defaultSettings: MerchantUiSettings = {
+  backendBaseURL: buildDefaultBackendBaseURL(),
+};
+
+const codecForBankUISettings = (): Codec<MerchantUiSettings> =>
+  buildCodecForObject<MerchantUiSettings>()
+    .property("backendBaseURL", codecOptional(codecForString()))
+    .build("MerchantUiSettings");
+
+function removeUndefineField<T extends object>(obj: T): T {
+  const keys = Object.keys(obj) as Array<keyof T>;
+  return keys.reduce((prev, cur) => {
+    if (typeof prev[cur] === "undefined") {
+      delete prev[cur];
+    }
+    return prev;
+  }, obj);
+}
+
+export function fetchSettings(listener: (s: MerchantUiSettings) => void): void {
+  fetch("./settings.json")
+    .then((resp) => resp.json())
+    .then((json) => codecForBankUISettings().decode(json))
+    .then((result) =>
+      listener({
+        ...defaultSettings,
+        ...removeUndefineField(result),
+      }),
+    )
+    .catch((e) => {
+      console.log("failed to fetch settings", e);
+      listener(defaultSettings);
+    });
+}
+
+export function buildDefaultBackendBaseURL(): string {
+  if (typeof window !== "undefined") {
+    const currentLocation = new URL(
+      window.location.pathname,
+      window.location.origin,
+    ).href;
+    /**
+     * By default, merchant backend serves the html content
+     * from the /webui root. This should cover most of the 
+     * cases and the rootPath will be the merchant backend
+     * URL where the instances are
+     */
+    return canonicalizeBaseUrl(currentLocation.replace("/webui", ""));
+  }
+  throw Error("No default URL")
+}