[#82] added cozy-ui for internationnalisation (#267)

Co-authored-by: Camille Moussu <cmoussu@linagora.com>

src/features/Settings/SettingsSlice.ts

@@ -0,0 +1,26 @@
+import { createSlice, PayloadAction } from "@reduxjs/toolkit";
+
+export interface SettingsState {
+  language: string;
+}
+
+const savedLang = localStorage.getItem("lang");
+const defaultLang = savedLang ?? (window as any).LANG ?? "en";
+
+const initialState: SettingsState = {
+  language: defaultLang,
+};
+
+export const settingsSlice = createSlice({
+  name: "settings",
+  initialState,
+  reducers: {
+    setLanguage: (state, action: PayloadAction<string>) => {
+      state.language = action.payload;
+      localStorage.setItem("lang", action.payload);
+    },
+  },
+});
+
+export const { setLanguage } = settingsSlice.actions;
+export default settingsSlice.reducer;