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src/utils/getHS.ts

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+/*
+Copyright 2020 The Matrix.org Foundation C.I.C.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+import { useContext } from 'react';
+import HSContext, {
+    TempHSContext,
+    State,
+    HSOptions,
+} from '../contexts/HSContext';
+import { SafeLink } from '../parser/types';
+
+function selectedClient(link: SafeLink, hsOptions: State): string[] {
+    switch (hsOptions.option) {
+        case HSOptions.Unset:
+            return [];
+        case HSOptions.TrustedHSOnly:
+            return [hsOptions.hs];
+        case HSOptions.Any:
+            return [
+                ...link.identifier
+                    .split('/')
+                    .map((i) => 'https://' + i.split(':')[1]),
+                ...link.arguments.vias,
+            ];
+    }
+}
+
+export default function useHSs(link: SafeLink): string[] {
+    const [HSState] = useContext(HSContext);
+    const [TempHSState] = useContext(TempHSContext);
+
+    if (HSState.option !== HSOptions.Unset) {
+        return selectedClient(link, HSState);
+    } else if (TempHSState.option !== HSOptions.Unset) {
+        return selectedClient(link, TempHSState);
+    } else {
+        return [];
+    }
+}