[MIRROR] [TGUI 5.0 Prep] Removes context (#7455)

Co-authored-by: Selis <sirlionfur@hotmail.de>
Co-authored-by: Selis <selis@xynolabs.com>

tgui/packages/tgui-panel/ping/reducer.ts

@@ -0,0 +1,53 @@
+/**
+ * @file
+ * @copyright 2020 Aleksej Komarov
+ * @license MIT
+ */
+
+import { clamp01, scale } from 'common/math';
+import { pingFail, pingSuccess } from './actions';
+import { PING_MAX_FAILS, PING_ROUNDTRIP_BEST, PING_ROUNDTRIP_WORST } from './constants';
+
+type PingState = {
+  roundtrip: number | undefined;
+  roundtripAvg: number | undefined;
+  failCount: number;
+  networkQuality: number;
+};
+
+export const pingReducer = (state = {} as PingState, action) => {
+  const { type, payload } = action;
+
+  if (type === pingSuccess.type) {
+    const { roundtrip } = payload;
+    const prevRoundtrip = state.roundtripAvg || roundtrip;
+    const roundtripAvg = Math.round(prevRoundtrip * 0.4 + roundtrip * 0.6);
+    const networkQuality =
+      1 - scale(roundtripAvg, PING_ROUNDTRIP_BEST, PING_ROUNDTRIP_WORST);
+    return {
+      roundtrip,
+      roundtripAvg,
+      failCount: 0,
+      networkQuality,
+    };
+  }
+
+  if (type === pingFail.type) {
+    const { failCount = 0 } = state;
+    const networkQuality = clamp01(
+      state.networkQuality - failCount / PING_MAX_FAILS
+    );
+    const nextState: PingState = {
+      ...state,
+      failCount: failCount + 1,
+      networkQuality,
+    };
+    if (failCount > PING_MAX_FAILS) {
+      nextState.roundtrip = undefined;
+      nextState.roundtripAvg = undefined;
+    }
+    return nextState;
+  }
+
+  return state;
+};