give Battleships & Destroyers health, make shells more frequent & larger

src/core/game/Game.ts

@@ -35,6 +35,8 @@ export interface UnitInfo {
     cost: (player: Player) => Gold
     // Determines if its owner changes when its tile is conquered.
     territoryBound: boolean
+    maxHealth?: number,
+    damage?: number
 }
 
 export enum UnitType {
@@ -193,6 +195,8 @@ export interface Unit {
     owner(): Player
     isActive(): boolean
     info(): UnitInfo
+    hasHealth(): boolean
+    health(): number
 }
 
 export interface MutableUnit extends Unit {
@@ -200,6 +204,7 @@ export interface MutableUnit extends Unit {
     owner(): MutablePlayer
     setTroops(troops: number): void
     delete(displayerMessage?: boolean): void
+    modifyHealth(delta: number): void
 }
 
 export interface TerraNullius {

src/core/game/UnitImpl.ts

@@ -1,5 +1,5 @@
 import { MessageType } from "../../client/graphics/layers/EventsDisplay";
-import { simpleHash } from "../Util";
+import { simpleHash, within } from "../Util";
 import { MutableUnit, Tile, TerraNullius, UnitType, Player, UnitInfo } from "./Game";
 import { GameImpl } from "./GameImpl";
 import { PlayerImpl } from "./PlayerImpl";
@@ -8,6 +8,7 @@ import { TerraNulliusImpl } from "./TerraNulliusImpl";
 
 export class UnitImpl implements MutableUnit {
     private _active = true;
+    private _health: number
 
     constructor(
         private _type: UnitType,
@@ -15,7 +16,10 @@ export class UnitImpl implements MutableUnit {
         private _tile: Tile,
         private _troops: number,
         public _owner: PlayerImpl,
-    ) { }
+    ) {
+        // default to half health (or 1 is no health specified)
+        this._health = (this.g.unitInfo(_type).maxHealth ?? 2) / 2
+    }
 
     type(): UnitType {
         return this._type
@@ -35,6 +39,12 @@ export class UnitImpl implements MutableUnit {
     troops(): number {
         return this._troops;
     }
+    health(): number {
+        return this._health
+    }
+    hasHealth(): boolean {
+        return this.info().maxHealth != undefined
+    }
     tile(): Tile {
         return this._tile;
     }
@@ -57,6 +67,15 @@ export class UnitImpl implements MutableUnit {
         )
     }
 
+    modifyHealth(delta: number): void {
+        this._health = within(
+            this._health + delta,
+            0,
+            this.info().maxHealth ?? 1
+        )
+    }
+
+
     delete(displayMessage: boolean = true): void {
         if (!this.isActive()) {
             throw new Error(`cannot delete ${this} not active`)