1 files changed, 49 insertions, 0 deletions
diff --git a/opendc-web/opendc-web-ui/src/data/topology.js b/opendc-web/opendc-web-ui/src/data/topology.js
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+++ b/opendc-web/opendc-web-ui/src/data/topology.js
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+/*
+ * Copyright (c) 2021 AtLarge Research
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in all
+ * copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ */
+
+import { useSelector } from 'react-redux'
+
+/**
+ * Return the current active topology.
+ */
+export function useActiveTopology() {
+    return useSelector((state) => state.currentTopologyId !== '-1' && state.objects.topology[state.currentTopologyId])
+}
+
+/**
+ * Return the topologies for the active project.
+ */
+export function useProjectTopologies() {
+    return useSelector(({ currentProjectId, objects }) => {
+        if (currentProjectId === '-1' || !objects.project[currentProjectId]) {
+            return []
+        }
+
+        const topologies = objects.project[currentProjectId].topologyIds.map((t) => objects.topology[t])
+
+        if (topologies.filter((t) => !t).length > 0) {
+            return []
+        }
+
+        return topologies
+    })
+}