feat(pkg): Add pathfinding edge pkg to packages dir

packages/pathfinding-edge/src/edge/guaranteeWalkablePath.ts

@@ -0,0 +1,31 @@
+import type { Grid } from 'pathfinding'
+import { Position, XYPosition } from '@braks/vue-flow'
+
+type Direction = 'top' | 'bottom' | 'left' | 'right'
+
+export const getNextPointFromPosition = (point: XYPosition, position: Direction): XYPosition => {
+  switch (position) {
+    case 'top':
+      return { x: point.x, y: point.y - 1 }
+    case 'bottom':
+      return { x: point.x, y: point.y + 1 }
+    case 'left':
+      return { x: point.x - 1, y: point.y }
+    case 'right':
+      return { x: point.x + 1, y: point.y }
+  }
+}
+
+/**
+ * Guarantee that the path is walkable, even if the point is inside a non
+ * walkable area, by adding a walkable path in the direction of the point's
+ * Position.
+ */
+export const guaranteeWalkablePath = (grid: Grid, point: XYPosition, position: Position) => {
+  let node = grid.getNodeAt(point.x, point.y)
+  while (!node.walkable) {
+    grid.setWalkableAt(node.x, node.y, true)
+    const next = getNextPointFromPosition(node, position)
+    node = grid.getNodeAt(next.x, next.y)
+  }
+}