1 files changed, 110 insertions, 0 deletions
diff --git a/packages/merchant-backend-ui/src/hooks/index.ts b/packages/merchant-backend-ui/src/hooks/index.ts
new file mode 100644
index 000000000..19d672ad3
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+++ b/packages/merchant-backend-ui/src/hooks/index.ts
@@ -0,0 +1,110 @@
+/*
+ This file is part of GNU Taler
+ (C) 2021 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/>
+ */
+
+/**
+*
+* @author Sebastian Javier Marchano (sebasjm)
+*/
+
+import { StateUpdater, useCallback, useState } from "preact/hooks";
+import { ValueOrFunction } from '../utils/types';
+
+
+const calculateRootPath = () => {
+  const rootPath = typeof window !== undefined ? window.location.origin + window.location.pathname : '/'
+  return rootPath
+}
+
+export function useBackendURL(url?: string): [string, boolean, StateUpdater<string>, () => void] {
+  const [value, setter] = useNotNullLocalStorage('backend-url', url || calculateRootPath())
+  const [triedToLog, setTriedToLog] = useLocalStorage('tried-login')
+
+  const checkedSetter = (v: ValueOrFunction<string>) => {
+    setTriedToLog('yes')
+    return setter(p => (v instanceof Function ? v(p) : v).replace(/\/$/, ''))
+  }
+
+  const resetBackend = () => {
+    setTriedToLog(undefined)
+  }
+  return [value, !!triedToLog, checkedSetter, resetBackend]
+}
+
+export function useBackendDefaultToken(): [string | undefined, StateUpdater<string | undefined>] {
+  return useLocalStorage('backend-token')
+}
+
+export function useBackendInstanceToken(id: string): [string | undefined, StateUpdater<string | undefined>] {
+  const [token, setToken] = useLocalStorage(`backend-token-${id}`)
+  const [defaultToken, defaultSetToken] = useBackendDefaultToken()
+
+  // instance named 'default' use the default token
+  if (id === 'default') {
+    return [defaultToken, defaultSetToken]
+  }
+
+  return [token, setToken]
+}
+
+export function useLang(initial?: string): [string, StateUpdater<string>] {
+  const browserLang = typeof window !== "undefined" ? navigator.language || (navigator as any).userLanguage : undefined;
+  const defaultLang = (browserLang || initial || 'en').substring(0, 2)
+  return useNotNullLocalStorage('lang-preference', defaultLang)
+}
+
+export function useLocalStorage(key: string, initialValue?: string): [string | undefined, StateUpdater<string | undefined>] {
+  const [storedValue, setStoredValue] = useState<string | undefined>((): string | undefined => {
+    return typeof window !== "undefined" ? window.localStorage.getItem(key) || initialValue : initialValue;
+  });
+
+  const setValue = (value?: string | ((val?: string) => string | undefined)) => {
+    setStoredValue(p => {
+      const toStore = value instanceof Function ? value(p) : value
+      if (typeof window !== "undefined") {
+        if (!toStore) {
+          window.localStorage.removeItem(key)
+        } else {
+          window.localStorage.setItem(key, toStore);
+        }
+      }
+      return toStore
+    })
+  };
+
+  return [storedValue, setValue];
+}
+
+export function useNotNullLocalStorage(key: string, initialValue: string): [string, StateUpdater<string>] {
+  const [storedValue, setStoredValue] = useState<string>((): string => {
+    return typeof window !== "undefined" ? window.localStorage.getItem(key) || initialValue : initialValue;
+  });
+
+  const setValue = (value: string | ((val: string) => string)) => {
+    const valueToStore = value instanceof Function ? value(storedValue) : value;
+    setStoredValue(valueToStore);
+    if (typeof window !== "undefined") {
+      if (!valueToStore) {
+        window.localStorage.removeItem(key)
+      } else {
+        window.localStorage.setItem(key, valueToStore);
+      }
+    }
+  };
+
+  return [storedValue, setValue];
+}
+
+