feat: implement getAttachments

2 files changed, 42 insertions, 19 deletions

diff --git a/src/Cell/Cell.test.ts b/src/Cell/Cell.test.ts
index 56f227f..0931130 100644
--- a/src/Cell/Cell.test.ts
+++ b/src/Cell/Cell.test.ts
@@ -2,7 +2,7 @@ import assert from 'assert';
 import Cell, { Direction, Item } from './Cell';
 
 const { North, East, South, West } = Direction;
-const { Road, Town, Empty, River, Church } = Item;
+const { Road, Town, Empty, River } = Item;
 
 describe('Cell', () => {
   describe('getSide', () => {
@@ -36,15 +36,17 @@ describe('Cell', () => {
     });
   });
 
-  describe('isAttachable', () => {
-    it('Should correctly test if cell is attachable', () => {
-      const cell = new Cell(Church, [Road, Town, Empty, River]);
-      const other = new Cell(Empty, [Road, Road, Town, Road], 3);
-
-      assert.strictEqual(cell.isAttachable(other, North), true);
-      assert.strictEqual(cell.isAttachable(other, East), true);
-      assert.strictEqual(cell.isAttachable(other, South), false);
-      assert.strictEqual(cell.isAttachable(other, West), false);
+  describe('getAttachments', () => {
+    it('Should correclty list legal attachments', () => {
+      const attachTo = new Cell(Town, [Road, Town, Town, Road])
+      const cell = new Cell(Road, [Empty, Road, Road, Empty])
+
+      const attachments = attachTo.getAttachments(cell);
+      assert.strictEqual(attachments.length, 4);
+      assert.deepStrictEqual(attachments[0], { side: 0, rotation: 0, cell, attachTo });
+      assert.deepStrictEqual(attachments[1], { side: 0, rotation: 1, cell, attachTo });
+      assert.deepStrictEqual(attachments[2], { side: 3, rotation: 0, cell, attachTo });
+      assert.deepStrictEqual(attachments[3], { side: 3, rotation: 3, cell, attachTo });
     });
   });
 });
diff --git a/src/Cell/Cell.ts b/src/Cell/Cell.ts
index 23fdc9e..70bb792 100644
--- a/src/Cell/Cell.ts
+++ b/src/Cell/Cell.ts
@@ -1,5 +1,8 @@
+import _ from 'lodash';
 import Debug, { Debugger } from 'debug';
 
+const debug = Debug('cell');
+
 export enum Direction {
   North,
   East,
@@ -15,9 +18,18 @@ export enum Item {
   Church = "C",
 }
 
+export interface Attachment {
+  attachTo: Cell;
+  side: Direction;
+  cell: Cell;
+  rotation: number; // Clockwise rotation of a cell
+}
+
+
 export default class Cell {
   center: Item;
   private sides: [Item, Item, Item, Item];
+  neighbors: [Cell, Cell, Cell, Cell];
   private orientation: number // amount of 90-degree counter-clockwise rotations from original orientation
   shield?: boolean;
 
@@ -28,12 +40,6 @@ export default class Cell {
     this.sides = sides;
     this.shield = shield;
     this.orientation = orientation;
-
-    this.debug = Debug('cell');
-  }
-
-  toString() {
-    return;
   }
 
   print() {
@@ -45,11 +51,26 @@ export default class Cell {
   }
 
   rotate(rotation = 1) {
-    this.debug(`Rotating ${rotation} clockwise`)
+    debug(`Rotating ${rotation} clockwise`)
     this.orientation = this.orientation - rotation;
   }
 
-  isAttachable(cell: Cell, side: Direction) {
-    return (this.getSide(side) === cell.getSide(side + 2));
+  getAttachments(cell: Cell) {
+    return _.flatten([0, 1, 2, 3].map(side => {
+      const item = this.getSide(side);
+      return [0, 1, 2, 3]
+        .filter(rotation => cell.getSide(side - rotation + 2) === item)
+        .map(rotation => ({
+          cell,
+          rotation,
+          side,
+          attachTo: this as Cell
+        }))
+    }));
+  }
+
+  attach(cell: Cell, side: Direction) {
+    if (this.neighbors[side]) throw new Error('There is something already attached to this side!');
+    this.neighbors[side] = cell;
   }
 }