allow alliance extension Fixes #491 (#1314)

## Description:

About 30s before an alliance is about to expire, both players receive a
prompt to extend the alliance. If both players agree the alliance is
extended.

## Please complete the following:

- [x] I have added screenshots for all UI updates
- [x] I process any text displayed to the user through translateText()
and I've added it to the en.json file
- [x] I have added relevant tests to the test directory
- [x] I confirm I have thoroughly tested these changes and take full
responsibility for any bugs introduced
- [x] I understand that submitting code with bugs that could have been
caught through manual testing blocks releases and new features for all
contributors

## Please put your Discord username so you can be contacted if a bug or
regression is found:

evan

src/client/Transport.ts

@@ -67,6 +67,10 @@ export class SendAllianceReplyIntentEvent implements GameEvent {
   ) {}
 }
 
+export class SendAllianceExtensionIntentEvent implements GameEvent {
+  constructor(public readonly recipient: PlayerView) {}
+}
+
 export class SendSpawnIntentEvent implements GameEvent {
   constructor(public readonly cell: Cell) {}
 }
@@ -194,6 +198,9 @@ export class Transport {
     this.eventBus.on(SendAllianceReplyIntentEvent, (e) =>
       this.onAllianceRequestReplyUIEvent(e),
     );
+    this.eventBus.on(SendAllianceExtensionIntentEvent, (e) =>
+      this.onSendAllianceExtensionIntent(e),
+    );
     this.eventBus.on(SendBreakAllianceIntentEvent, (e) =>
       this.onBreakAllianceRequestUIEvent(e),
     );
@@ -419,6 +426,16 @@ export class Transport {
     });
   }
 
+  private onSendAllianceExtensionIntent(
+    event: SendAllianceExtensionIntentEvent,
+  ) {
+    this.sendIntent({
+      type: "allianceExtension",
+      clientID: this.lobbyConfig.clientID,
+      recipient: event.recipient.id(),
+    });
+  }
+
   private onSendSpawnIntentEvent(event: SendSpawnIntentEvent) {
     this.sendIntent({
       type: "spawn",

src/client/Utils.ts

@@ -141,6 +141,7 @@ export function getMessageTypeClasses(type: MessageType): string {
     case MessageType.SAM_MISS:
     case MessageType.ALLIANCE_EXPIRED:
     case MessageType.NAVAL_INVASION_INBOUND:
+    case MessageType.RENEW_ALLIANCE:
       return severityColors["warn"];
     case MessageType.CHAT:
     case MessageType.ALLIANCE_REQUEST:

src/client/graphics/layers/EventsDisplay.ts

@@ -32,6 +32,7 @@ import {
 import {
   CancelAttackIntentEvent,
   CancelBoatIntentEvent,
+  SendAllianceExtensionIntentEvent,
   SendAllianceReplyIntentEvent,
 } from "../../Transport";
 import { Layer } from "./Layer";
@@ -45,7 +46,6 @@ import {
   GoToUnitEvent,
 } from "./Leaderboard";
 
-import { UserSettings } from "../../../core/game/UserSettings";
 import { getMessageTypeClasses, translateText } from "../../Utils";
 
 interface GameEvent {
@@ -73,9 +73,11 @@ export class EventsDisplay extends LitElement implements Layer {
   public eventBus: EventBus;
   public game: GameView;
 
-  private userSettings: UserSettings = new UserSettings();
   private active: boolean = false;
   private events: GameEvent[] = [];
+
+  // allianceID -> last checked at tick
+  private alliancesCheckedAt = new Map<number, Tick>();
   @state() private incomingAttacks: AttackUpdate[] = [];
   @state() private outgoingAttacks: AttackUpdate[] = [];
   @state() private outgoingLandAttacks: AttackUpdate[] = [];
@@ -182,6 +184,8 @@ export class EventsDisplay extends LitElement implements Layer {
       return;
     }
 
+    this.checkForAllianceExpirations();
+
     const updates = this.game.updatesSinceLastTick();
     if (updates) {
       for (const [ut, fn] of this.updateMap) {
@@ -235,6 +239,64 @@ export class EventsDisplay extends LitElement implements Layer {
     }
   }
 
+  private checkForAllianceExpirations() {
+    const myPlayer = this.game.myPlayer();
+    if (!myPlayer) return;
+
+    for (const alliance of myPlayer.alliances()) {
+      if (
+        alliance.expiresAt >
+        this.game.ticks() + this.game.config().allianceExtensionPromptOffset()
+      ) {
+        continue;
+      }
+
+      if (
+        (this.alliancesCheckedAt.get(alliance.id) ?? 0) >=
+        this.game.ticks() - this.game.config().allianceExtensionPromptOffset()
+      ) {
+        // We've already displayed a message for this alliance.
+        continue;
+      }
+
+      this.alliancesCheckedAt.set(alliance.id, this.game.ticks());
+
+      const other = this.game.player(alliance.other) as PlayerView;
+
+      this.addEvent({
+        description: translateText("events_display.about_to_expire", {
+          name: other.name(),
+        }),
+        type: MessageType.RENEW_ALLIANCE,
+        duration: this.game.config().allianceExtensionPromptOffset() - 3 * 10, // 3 second buffer
+        buttons: [
+          {
+            text: translateText("events_display.focus"),
+            className: "btn-gray",
+            action: () => this.eventBus.emit(new GoToPlayerEvent(other)),
+            preventClose: true,
+          },
+          {
+            text: translateText("events_display.renew_alliance", {
+              name: other.name(),
+            }),
+            className: "btn",
+            action: () =>
+              this.eventBus.emit(new SendAllianceExtensionIntentEvent(other)),
+          },
+          {
+            text: translateText("events_display.ignore"),
+            className: "btn-info",
+            action: () => {},
+          },
+        ],
+        highlight: true,
+        createdAt: this.game.ticks(),
+        focusID: other.smallID(),
+      });
+    }
+  }
+
   private addEvent(event: GameEvent) {
     this.events = [...this.events, event];
     if (this._hidden === true) {

src/client/graphics/layers/PlayerPanel.ts

@@ -176,11 +176,9 @@ export class PlayerPanel extends LitElement implements Layer {
       if (myPlayer !== null && myPlayer.isAlive()) {
         this.actions = await myPlayer.actions(this.tile);
 
-        if (this.actions?.interaction?.allianceCreatedAtTick !== undefined) {
-          const createdAt = this.actions.interaction.allianceCreatedAtTick;
-          const durationTicks = this.g.config().allianceDuration();
-          const expiryTick = createdAt + durationTicks;
-          const remainingTicks = expiryTick - this.g.ticks();
+        if (this.actions?.interaction?.allianceExpiresAt !== undefined) {
+          const expiresAt = this.actions.interaction.allianceExpiresAt;
+          const remainingTicks = expiresAt - this.g.ticks();
 
           if (remainingTicks > 0) {
             const remainingSeconds = Math.max(