Nation build order improvements 🤖 (#2833)

## Description:

My first PR about the nation build order.
This one is a bit important for HumansVsNations.

- Nations build more SAMs in team games
- Nations build less factories if they have access to the ocean (instead
of focusing ports and factories with the same priority)
- Nations no longer place defense posts "without reason" - only when
they share a border with someone they haven't allied

I'm planning to make the build order a bit different based on
difficulty.

## 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

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

FloPinguin

src/core/execution/NationExecution.ts

@@ -2,6 +2,7 @@ import {
   Difficulty,
   Execution,
   Game,
+  GameMode,
   Gold,
   Nation,
   Player,
@@ -250,17 +251,31 @@ export class NationExecution implements Execution {
 
   private handleUnits() {
     if (this.warshipBehavior === null) throw new Error("not initialized");
+    const hasCoastalTiles = this.hasCoastalTiles();
+    const isTeamGame = this.mg.config().gameConfig().gameMode === GameMode.Team;
     return (
       this.maybeSpawnStructure(UnitType.City, (num) => num) ||
       this.maybeSpawnStructure(UnitType.Port, (num) => num) ||
       this.warshipBehavior.maybeSpawnWarship() ||
-      this.maybeSpawnStructure(UnitType.Factory, (num) => num) ||
+      this.maybeSpawnStructure(UnitType.Factory, (num) =>
+        hasCoastalTiles ? num * 3 : num,
+      ) ||
       this.maybeSpawnStructure(UnitType.DefensePost, (num) => (num + 2) ** 2) ||
-      this.maybeSpawnStructure(UnitType.SAMLauncher, (num) => num ** 2) ||
+      this.maybeSpawnStructure(UnitType.SAMLauncher, (num) =>
+        isTeamGame ? num : num ** 2,
+      ) ||
       this.maybeSpawnStructure(UnitType.MissileSilo, (num) => num ** 2)
     );
   }
 
+  private hasCoastalTiles(): boolean {
+    if (this.player === null) throw new Error("not initialized");
+    for (const tile of this.player.borderTiles()) {
+      if (this.mg.isOceanShore(tile)) return true;
+    }
+    return false;
+  }
+
   private maybeSpawnStructure(
     type: UnitType,
     multiplier: (num: number) => number,
@@ -294,6 +309,7 @@ export class NationExecution implements Execution {
         : randTerritoryTileArray(this.random, this.mg, this.player, 25);
     if (tiles.length === 0) return null;
     const valueFunction = structureSpawnTileValue(this.mg, this.player, type);
+    if (valueFunction === null) return null;
     let bestTile: TileRef | null = null;
     let bestValue = 0;
     for (const t of tiles) {

src/core/execution/nation/structureSpawnTileValue.ts

@@ -1,4 +1,4 @@
-import { Game, Player, Relation, UnitType } from "../../game/Game";
+import { Game, Player, PlayerType, Relation, UnitType } from "../../game/Game";
 import { TileRef } from "../../game/GameMap";
 import { closestTile, closestTwoTiles } from "../Util";
 
@@ -6,7 +6,7 @@ export function structureSpawnTileValue(
   mg: Game,
   player: Player,
   type: UnitType,
-): (tile: TileRef) => number {
+): ((tile: TileRef) => number) | null {
   const borderTiles = player.borderTiles();
   const otherUnits = player.units(type);
   // Prefer spacing structures out of atom bomb range
@@ -57,6 +57,22 @@ export function structureSpawnTileValue(
       };
     }
     case UnitType.DefensePost: {
+      // Check if we have any non-friendly non-bot neighbors
+      const hasHostileNeighbor =
+        player
+          .neighbors()
+          .filter(
+            (n): n is Player =>
+              n.isPlayer() &&
+              player.isFriendly(n) === false &&
+              n.type() !== PlayerType.Bot,
+          ).length > 0;
+
+      // Don't build defense posts if there is no danger
+      if (!hasHostileNeighbor) {
+        return null;
+      }
+
       return (tile) => {
         let w = 0;
 
@@ -79,6 +95,7 @@ export function structureSpawnTileValue(
             if (id === player.smallID()) continue;
             const neighbor = mg.playerBySmallID(id);
             if (!neighbor.isPlayer()) continue;
+            if (neighbor.type() === PlayerType.Bot) continue;
             neighbors.add(neighbor);
           }
           for (const neighbor of neighbors) {