NPCs send boats at enemies when not adjacent

src/core/execution/FakeHumanExecution.ts

@@ -16,6 +16,7 @@ import { NukeExecution } from "./NukeExecution";
 import { MissileSiloExecution } from "./MissileSiloExecution";
 import { EmojiExecution } from "./EmojiExecution";
 import { AllianceRequestReplyExecution } from "./alliance/AllianceRequestReplyExecution";
+import { closestTwoTiles } from "./Util";
 
 export class FakeHumanExecution implements Execution {
 
@@ -186,10 +187,17 @@ export class FakeHumanExecution implements Execution {
             }
         }
 
+        if (this.player.isAlliedWith(this.enemy)) {
+            this.enemy = null
+            return
+        }
+
         if (this.enemy) {
             this.maybeSendNuke(this.enemy)
-            if (this.player.sharesBorderWith(this.enemy) && !this.player.isAlliedWith(this.enemy)) {
+            if (this.player.sharesBorderWith(this.enemy)) {
                 this.sendAttack(this.enemy)
+            } else {
+                this.maybeSendBoatAttack(this.enemy)
             }
             return
         }
@@ -221,6 +229,24 @@ export class FakeHumanExecution implements Execution {
         }
     }
 
+    private maybeSendBoatAttack(other: Player) {
+        const closest = closestTwoTiles(
+            Array.from(this.player.borderTiles()).filter(t => t.isOceanShore()),
+            Array.from(other.borderTiles()).filter(t => t.isOceanShore())
+        )
+        if (closest == null) {
+            return
+        }
+        if (manhattanDist(closest.x.cell(), closest.y.cell()) < this.mg.config().boatMaxDistance()) {
+            this.mg.addExecution(new TransportShipExecution(
+                this.player.id(),
+                other.id(),
+                closest.y.cell(),
+                this.player.troops() / 5
+            ))
+        }
+    }
+
     private handleUnits() {
         const ports = this.player.units(UnitType.Port)
         if (ports.length == 0 && this.player.gold() > this.cost(UnitType.Port)) {

src/core/execution/Util.ts

@@ -1,4 +1,4 @@
-import {Game, Cell} from "../game/Game";
+import { Game, Cell, Tile } from "../game/Game";
 
 
 export function getSpawnCells(gs: Game, cell: Cell): Cell[] {
@@ -23,3 +23,48 @@ export function getSpawnCells(gs: Game, cell: Cell): Cell[] {
     }
     return result;
 }
+
+export function closestTwoTiles(x: Iterable<Tile>, y: Iterable<Tile>): { x: Tile, y: Tile } {
+    const xSorted = Array.from(x).sort((a, b) => a.cell().x - b.cell().x);
+    const ySorted = Array.from(y).sort((a, b) => a.cell().x - b.cell().x);
+
+    if (xSorted.length == 0 || ySorted.length == 0) {
+        return null;
+    }
+
+    let i = 0;
+    let j = 0;
+    let minDistance = Infinity;
+    let result = { x: xSorted[0], y: ySorted[0] };
+
+    while (i < xSorted.length && j < ySorted.length) {
+        const currentX = xSorted[i];
+        const currentY = ySorted[j];
+
+        const distance =
+            Math.abs(currentX.cell().x - currentY.cell().x) +
+            Math.abs(currentX.cell().y - currentY.cell().y);
+
+        if (distance < minDistance) {
+            minDistance = distance;
+            result = { x: currentX, y: currentY };
+        }
+
+        // If we're at the end of X, must move Y forward
+        if (i === xSorted.length - 1) {
+            j++;
+        }
+        // If we're at the end of Y, must move X forward
+        else if (j === ySorted.length - 1) {
+            i++;
+        }
+        // Otherwise, move whichever pointer has smaller x value
+        else if (currentX.cell().x < currentY.cell().x) {
+            i++;
+        } else {
+            j++;
+        }
+    }
+
+    return result;
+}