Draw frozen combat in the new UI.

https://github.com/dcs-liberation/dcs_liberation/issues/2039

client/src/api/combat.ts

@@ -0,0 +1,8 @@
+import { LatLng } from "leaflet";
+
+export default interface Combat {
+  id: string;
+  flight_position: LatLng | null;
+  target_positions: LatLng[] | null;
+  footprint: LatLng[][] | null;
+}

client/src/api/combatSlice.ts

@@ -0,0 +1,42 @@
+import { RootState } from "../app/store";
+import Combat from "./combat";
+import { PayloadAction, createSlice } from "@reduxjs/toolkit";
+
+interface CombatState {
+  combat: { [key: string]: Combat };
+}
+
+const initialState: CombatState = {
+  combat: {},
+};
+
+export const combatSlice = createSlice({
+  name: "combat",
+  initialState,
+  reducers: {
+    setCombat: (state, action: PayloadAction<Combat[]>) => {
+      state.combat = {};
+      for (const combat of action.payload) {
+        state.combat[combat.id] = combat;
+      }
+    },
+    newCombat: (state, action: PayloadAction<Combat>) => {
+      const combat = action.payload;
+      state.combat[combat.id] = combat;
+    },
+    updateCombat: (state, action: PayloadAction<Combat>) => {
+      const combat = action.payload;
+      state.combat[combat.id] = combat;
+    },
+    endCombat: (state, action: PayloadAction<string>) => {
+      delete state.combat[action.payload];
+    },
+  },
+});
+
+export const { setCombat, newCombat, updateCombat, endCombat } =
+  combatSlice.actions;
+
+export const selectCombat = (state: RootState) => state.combat;
+
+export default combatSlice.reducer;

client/src/api/eventstream.tsx

@@ -1,5 +1,7 @@
 import { AppDispatch } from "../app/store";
 import backend from "./backend";
+import Combat from "./combat";
+import { endCombat, newCombat, updateCombat } from "./combatSlice";
 import { updateControlPoint } from "./controlPointsSlice";
 import { ControlPoint } from "./controlpoint";
 import { Flight } from "./flight";
@@ -21,14 +23,10 @@ import Tgo from "./tgo";
 import { updateTgo } from "./tgosSlice";
 import { LatLng } from "leaflet";
 
-// Placeholder. We don't use this yet. This is just here so we can flesh out the
-// update events model.
-interface FrozenCombat {}
-
 interface GameUpdateEvents {
   updated_flight_positions: { [id: string]: LatLng };
-  new_combats: FrozenCombat[];
-  updated_combats: FrozenCombat[];
+  new_combats: Combat[];
+  updated_combats: Combat[];
   ended_combats: string[];
   navmesh_updates: boolean[];
   unculled_zones_updated: boolean;
@@ -55,6 +53,18 @@ export const handleStreamedEvents = (
     dispatch(updateFlightPosition([id, position]));
   }
 
+  for (const combat of events.new_combats) {
+    dispatch(newCombat(combat));
+  }
+
+  for (const combat of events.updated_combats) {
+    dispatch(updateCombat(combat));
+  }
+
+  for (const id of events.ended_combats) {
+    dispatch(endCombat(id));
+  }
+
   for (const flight of events.new_flights) {
     dispatch(registerFlight(flight));
   }