1 files changed, 143 insertions, 0 deletions
diff --git a/packages/challenger-ui/src/hooks/session.ts b/packages/challenger-ui/src/hooks/session.ts
new file mode 100644
index 000000000..ed7ea8986
--- /dev/null
+++ b/packages/challenger-ui/src/hooks/session.ts
@@ -0,0 +1,143 @@
+/*
+ This file is part of GNU Taler
+ (C) 2022-2024 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 {
+  ChallengerApi,
+  Codec,
+  buildCodecForObject,
+  codecForBoolean,
+  codecForChallengeStatus,
+  codecForNumber,
+  codecForString,
+  codecForStringURL,
+  codecOptional,
+} from "@gnu-taler/taler-util";
+import { buildStorageKey, useLocalStorage } from "@gnu-taler/web-util/browser";
+import { mutate } from "swr";
+
+/**
+ * Has the information to reach and
+ * authenticate at the bank's backend.
+ */
+export type SessionId = {
+  clientId: string;
+  redirectURL: string;
+  state: string;
+};
+
+export type LastChallengeResponse = {
+  attemptsLeft: number;
+  nextSend: string;
+  transmitted: boolean;
+};
+
+export type SessionState = SessionId & {
+  lastTry: LastChallengeResponse | undefined;
+  lastStatus: ChallengerApi.ChallengeStatus | undefined;
+  completedURL: string | undefined;
+};
+export const codecForLastChallengeResponse = (): Codec<LastChallengeResponse> =>
+  buildCodecForObject<LastChallengeResponse>()
+    .property("attemptsLeft", codecForNumber())
+    .property("nextSend", codecForString())
+    .property("transmitted", codecForBoolean())
+    .build("LastChallengeResponse");
+
+export const codecForSessionState = (): Codec<SessionState> =>
+  buildCodecForObject<SessionState>()
+    .property("clientId", codecForString())
+    .property("redirectURL", codecForStringURL())
+    .property("completedURL", codecOptional(codecForStringURL()))
+    .property("state", codecForString())
+    .property("lastStatus", codecOptional(codecForChallengeStatus()))
+    .property("lastTry", codecOptional(codecForLastChallengeResponse()))
+    .build("SessionState");
+
+export interface SessionStateHandler {
+  state: SessionState | undefined;
+  start(s: SessionId): void;
+  accepted(l: LastChallengeResponse): void;
+  completed(e: URL): void;
+  updateStatus(s: ChallengerApi.ChallengeStatus): void;
+}
+
+const SESSION_STATE_KEY = buildStorageKey(
+  "challenger-session",
+  codecForSessionState(),
+);
+
+/**
+ * Return getters and setters for
+ * login credentials and backend's
+ * base URL.
+ */
+export function useSessionState(): SessionStateHandler {
+  const { value: state, update } = useLocalStorage(SESSION_STATE_KEY);
+
+  return {
+    state,
+    start(info) {
+      update({
+        ...info,
+        lastTry: undefined,
+        completedURL: undefined,
+        lastStatus: undefined,
+      });
+      cleanAllCache();
+    },
+    accepted(lastTry) {
+      if (!state) return;
+      update({
+        ...state,
+        lastTry,
+      });
+    },
+    completed(url) {
+      if (!state) return;
+      update({
+        ...state,
+        completedURL: url.href,
+      });
+    },
+    updateStatus(st: ChallengerApi.ChallengeStatus) {
+      if (!state) return;
+      if (!state.lastStatus) {
+        update({
+          ...state,
+          lastStatus: st,
+        });
+        return;
+      }
+      // current status
+      const ls = state.lastStatus;
+      if (
+        ls.changes_left !== st.changes_left ||
+        ls.fix_address !== st.fix_address ||
+        ls.last_address !== st.last_address
+      ) {
+        update({
+          ...state,
+          lastStatus: st,
+        });
+        return;
+      }
+    },
+  };
+}
+
+function cleanAllCache(): void {
+  mutate(() => true, undefined, { revalidate: false });
+}