refactor: separate TileOnBoard class

1 files changed, 46 insertions, 0 deletions

diff --git a/src/Tile/TileOnBoard.ts b/src/Tile/TileOnBoard.ts
new file mode 100644
index 0000000..65f3731
--- /dev/null
+++ b/src/Tile/TileOnBoard.ts
@@ -0,0 +1,46 @@
+import _ from 'lodash';
+import Tile, { Feature, Direction } from './Tile';
+
+export interface Attachment {
+  attachTo: Tile;
+  side: Direction;
+  tile: Tile;
+  rotation: number; // Clockwise rotation of a tile
+}
+
+export default class TileOnBoard extends Tile {
+  neighbors: [Tile, Tile, Tile, Tile];
+  private orientation: number // amount of 90-degree counter-clockwise rotations from original orientation
+
+  constructor(center: Feature, sides: [Feature, Feature, Feature, Feature], shield = false, orientation = 0) {
+    super(center, sides, shield);
+    this.orientation = orientation;
+  }
+
+  getSide(direction: Direction) {
+    return this.sides[(((this.orientation + direction) % 4) + 4) % 4];
+  }
+
+  rotate(rotation = 1) {
+    this.orientation = this.orientation - rotation;
+  }
+
+  getAttachments(tile: Tile): Attachment[] {
+    return _.flatten([0, 1, 2, 3].map(side => {
+      const item = this.getSide(side);
+      return [0, 1, 2, 3]
+        .filter(rotation => tile.getSide(side - rotation + 2) === item)
+        .map(rotation => ({
+          tile,
+          rotation,
+          side,
+          attachTo: this as Tile
+        }))
+    }));
+  }
+
+  attach(tile: Tile, side: Direction) {
+    if (this.neighbors[side]) throw new Error('There is something already attached to this side!');
+    this.neighbors[side] = tile;
+  }
+}