Reroute trade ships when destination port is no longer valid

src/core/execution/TradeShipExecution.ts

@@ -66,6 +66,8 @@ export class TradeShipExecution implements Execution {
 
     const tradeShipOwner = this.tradeShip.owner();
     const dstPortOwner = this._dstPort.owner();
+    const curTile = this.tradeShip.tile();
+
     if (this.wasCaptured !== true && this.origOwner !== tradeShipOwner) {
       // Store as variable in case ship is recaptured by previous owner
       this.wasCaptured = true;
@@ -79,42 +81,51 @@ export class TradeShipExecution implements Execution {
       return;
     }
 
+    if (!this.tradeShip.isActive()) {
+      this.active = false;
+      return;
+    }
+
+    // Handle embargo or inactives ports destinations
     if (
       !this.wasCaptured &&
       (!this._dstPort.isActive() || !tradeShipOwner.canTrade(dstPortOwner))
     ) {
-      this.tradeShip.delete(false);
-      this.active = false;
-      return;
-    }
+      const newPort = this.findNearestValidPort(
+        curTile,
+        (p) => p !== this.origOwner && p.canTrade(tradeShipOwner),
+      );
 
-    const curTile = this.tradeShip.tile();
+      if (newPort === null) {
+        this.tradeShip.delete(false);
+        this.active = false;
+        return;
+      }
+      this._dstPort = newPort;
+      this.tradeShip.setTargetUnit(this._dstPort);
+      this.tradeShip.touch();
+      this.motionPlanDst = null; // Force motion plan re-recording
+    }
 
+    // Handle captured ship that needs rerouting to nearest new owner port
     if (
       this.wasCaptured &&
       (tradeShipOwner !== dstPortOwner || !this._dstPort.isActive())
     ) {
-      const myComponent = this.mg.getWaterComponent(curTile);
-      const nearestPort = findClosestBy(
-        tradeShipOwner.units(UnitType.Port),
-        (port) => this.mg.manhattanDist(port.tile(), curTile),
-        (port) =>
-          port.isActive() &&
-          !port.isMarkedForDeletion() &&
-          !port.isUnderConstruction() &&
-          myComponent !== null &&
-          this.mg.hasWaterComponent(port.tile(), myComponent),
+      const newPort = this.findNearestValidPort(
+        curTile,
+        (p) => p === tradeShipOwner,
       );
-      if (nearestPort === null) {
+
+      if (newPort === null) {
         this.tradeShip.delete(false);
         this.active = false;
         return;
-      } else {
-        this._dstPort = nearestPort;
-        this.tradeShip.setTargetUnit(this._dstPort);
-        // Plan-driven units don't emit per-tick unit updates, so force a sync for the new target.
-        this.tradeShip.touch();
       }
+      this._dstPort = newPort;
+      this.tradeShip.setTargetUnit(this._dstPort);
+      this.tradeShip.touch();
+      this.motionPlanDst = null; // Force path recalc
     }
 
     if (curTile === this.dstPort()) {
@@ -230,4 +241,32 @@ export class TradeShipExecution implements Execution {
   dstPort(): TileRef {
     return this._dstPort.tile();
   }
+
+  private findNearestValidPort(
+    curTile: TileRef,
+    playerFilter: (p: Player) => boolean,
+  ): Unit | null {
+    const myComponent = this.mg.getWaterComponent(curTile);
+    if (myComponent === null) return null;
+
+    const eligiblePlayers = this.mg.players().filter(playerFilter);
+
+    const candidatePorts = eligiblePlayers.flatMap((p) =>
+      p.units(UnitType.Port),
+    );
+
+    const validPorts = candidatePorts.filter(
+      (port) =>
+        port.isActive() &&
+        !port.isMarkedForDeletion() &&
+        !port.isUnderConstruction() &&
+        this.mg.hasWaterComponent(port.tile(), myComponent),
+    );
+
+    if (validPorts.length === 0) return null;
+
+    return findClosestBy(validPorts, (port) =>
+      this.mg.manhattanDist(port.tile(), curTile),
+    );
+  }
 }

tests/core/executions/TradeShipExecution.test.ts

@@ -8,12 +8,15 @@ describe("TradeShipExecution", () => {
   let origOwner: Player;
   let dstOwner: Player;
   let pirate: Player;
+  let halfPirate: Player;
   let srcPort: Unit;
   let piratePort: Unit;
   let piratePort2: Unit;
+  let halfPiratePort: Unit;
   let tradeShip: Unit;
   let dstPort: Unit;
   let tradeShipExecution: TradeShipExecution;
+  let currentTarget: Unit | null = null;
 
   beforeEach(async () => {
     // Mock Game, Player, Unit, and required methods
@@ -48,12 +51,21 @@ describe("TradeShipExecution", () => {
     pirate = {
       id: vi.fn(() => 3),
       addGold: vi.fn(),
-      displayName: vi.fn(() => "Destination"),
+      displayName: vi.fn(() => "Destination 1"),
       units: vi.fn(() => [piratePort, piratePort2]),
       unitCount: vi.fn(() => 2),
       canTrade: vi.fn(() => true),
     } as any;
 
+    halfPirate = {
+      id: vi.fn(() => 4),
+      addGold: vi.fn(),
+      displayName: vi.fn(() => "Destination 2"),
+      units: vi.fn(() => [halfPiratePort]),
+      unitCount: vi.fn(() => 1),
+      canTrade: vi.fn(() => true),
+    } as any;
+
     piratePort = {
       id: vi.fn(() => 201),
       tile: vi.fn(() => 56),
@@ -72,6 +84,15 @@ describe("TradeShipExecution", () => {
       isMarkedForDeletion: vi.fn(() => false),
     } as any;
 
+    halfPiratePort = {
+      id: vi.fn(() => 301),
+      tile: vi.fn(() => 11),
+      owner: vi.fn(() => halfPirate),
+      isActive: vi.fn(() => true),
+      isUnderConstruction: vi.fn(() => false),
+      isMarkedForDeletion: vi.fn(() => false),
+    } as any;
+
     srcPort = {
       id: vi.fn(() => 101),
       tile: vi.fn(() => 10),
@@ -95,7 +116,10 @@ describe("TradeShipExecution", () => {
       owner: vi.fn(() => origOwner),
       id: vi.fn(() => 123),
       move: vi.fn(),
-      setTargetUnit: vi.fn(),
+      setTargetUnit: vi.fn((port: Unit) => {
+        currentTarget = port;
+      }),
+      targetUnit: vi.fn(() => currentTarget),
       setSafeFromPirates: vi.fn(),
       touch: vi.fn(),
       delete: vi.fn(),
@@ -109,6 +133,18 @@ describe("TradeShipExecution", () => {
       findPath: vi.fn((from: number) => [from]),
     } as any;
     tradeShipExecution["tradeShip"] = tradeShip;
+
+    vi.spyOn(game, "players").mockReturnValue([
+      origOwner,
+      dstOwner,
+      pirate,
+      halfPirate,
+    ]);
+    vi.spyOn(game, "getWaterComponent").mockReturnValue(1);
+    vi.spyOn(game, "hasWaterComponent").mockReturnValue(true);
+    vi.spyOn(game, "manhattanDist").mockReturnValue(10);
+
+    currentTarget = null;
   });
 
   it("should initialize and tick without errors", () => {
@@ -135,6 +171,22 @@ describe("TradeShipExecution", () => {
     expect(tradeShip.setTargetUnit).toHaveBeenCalledWith(piratePort);
   });
 
+  it("should pick another port if destination is embargoed and ship not captured", () => {
+    dstOwner.canTrade = vi.fn(() => false);
+    halfPirate.canTrade = vi.fn(() => true);
+    pirate.canTrade = vi.fn(() => false);
+    origOwner.canTrade = vi.fn((target: Player) => {
+      if (target.id() === halfPirate.id()) return true;
+      return false;
+    });
+
+    tradeShipExecution.tick(1);
+    expect(tradeShip.delete).not.toHaveBeenCalled();
+    expect(tradeShipExecution.isActive()).toBe(true);
+    expect(tradeShip.targetUnit()).toBe(halfPiratePort);
+    expect(tradeShip.touch).toHaveBeenCalled();
+  });
+
   it("should complete trade and award gold", () => {
     tradeShipExecution["pathFinder"] = {
       next: vi.fn(() => ({ status: PathStatus.COMPLETE, node: 32 })),