From c0f5a8f7f7257a36d7d6e9886753cdfedcd7d7fb Mon Sep 17 00:00:00 2001
From: = <=>
Date: Mon, 27 Apr 2020 10:49:30 +0200
Subject: [PATCH] added BFS

---
 kelner/src/algorithms/BFS/BFS.py     | 49 ++++++++++++++++++++++++++++
 kelner/src/managers/WaiterManager.py |  3 ++
 2 files changed, 52 insertions(+)
 create mode 100644 kelner/src/algorithms/BFS/BFS.py

diff --git a/kelner/src/algorithms/BFS/BFS.py b/kelner/src/algorithms/BFS/BFS.py
new file mode 100644
index 0000000..ddc1d38
--- /dev/null
+++ b/kelner/src/algorithms/BFS/BFS.py
@@ -0,0 +1,49 @@
+import queue
+
+
+class BFS:
+    def __init__(self, grid):
+        self.grid = grid
+        self.visited = []
+
+    def get_neighbors(self, node, grid):
+        dr = [-1, +1, 0, 0]
+        dc = [0, 0, +1, -1]
+        x = node[0]
+        y = node[1]
+        node = (x, y)
+        neighbors = []
+
+        for i in range(4):
+            new_col = x + dc[i]
+            new_row = y + dr[i]
+            node = (new_col, new_row)
+
+            if 0 <= new_row < len(grid) and 0 <= new_col < len(grid[0]):
+                if (new_col, new_row) not in self.visited:
+                    if grid[new_row][new_col] != 1:
+                        neighbors.append((new_col, new_row))
+
+        return neighbors
+
+    def find_path(self, start, end):
+        grid = self.grid
+        queue = [(start, [])]
+
+        while len(queue) > 0:
+            node, path = queue.pop(0)
+
+            path.append(node)
+            self.visited.append(node)
+
+            if node == end:
+                if len(path) > 1:
+                    path.pop(0)
+                return path
+
+            adj_nodes = self.get_neighbors(node, grid)
+            for item in adj_nodes:
+                if item not in self.visited:
+                    queue.append((item, path[:]))
+
+        return None
diff --git a/kelner/src/managers/WaiterManager.py b/kelner/src/managers/WaiterManager.py
index 2240637..e75a9d6 100644
--- a/kelner/src/managers/WaiterManager.py
+++ b/kelner/src/managers/WaiterManager.py
@@ -3,6 +3,7 @@ import time
 import sys
 from kelner.src.components.Table import Status
 from kelner.src.algorithms.AStar.Finder import Finder
+from kelner.src.algorithms.BFS.BFS import BFS
 
 
 # creates new thread
@@ -20,11 +21,13 @@ class WaiterManager (threading.Thread):
         if tables:
             reservedPlaces = self.__drawableManager.getReservedPlaces(waiter)
             finder = Finder(reservedPlaces)
+            # bfs = BFS(reservedPlaces)
             origin = (waiter.getX(), waiter.getY())
             for table in tables:
                 targets = finder.getNeighbours((table.getX(), table.getY()), False)
                 for target in targets:
                     if target is not None:
+                        # path = bfs.find_path(origin, target)
                         path = finder.getPath(origin, target, True)
                         if path:
                             result = len(path)