From 19acd22c9b853c613124c355a0ffa87067ef2b1f Mon Sep 17 00:00:00 2001
From: Stefan Harmuth <pennywise@drock.de>
Date: Sat, 10 Dec 2022 14:47:50 +0100
Subject: [PATCH] cleanly stop still running background intcode computers

---
 day15.py   |  7 +++----
 intcode.py | 40 +++++++++++++++++++++++++---------------
 2 files changed, 28 insertions(+), 19 deletions(-)

diff --git a/day15.py b/day15.py
index 9f2c2af..6e083af 100644
--- a/day15.py
+++ b/day15.py
@@ -51,7 +51,9 @@ class Day(AOCDay):
         comp = IntCode(self.getInputAsArraySplit(",", int))
         comp.start()
         pos = Coordinate(0, 0)
-        return discover(comp, Grid(), pos)
+        grid = discover(comp, Grid(), pos)
+        comp.stop()
+        return grid
 
     def part1(self) -> Any:
         return len(self.get_grid().getPath(Coordinate(0, 0), OXYGEN_POS, includeDiagonal=False, walls=[True])) - 1
@@ -63,10 +65,7 @@ class Day(AOCDay):
         grid.set(OXYGEN_POS, 2)
         count = 0
 
-        grid.print(true_char='#', false_char=' ', mark=[Coordinate(0, 0), OXYGEN_POS])
-
         while queue:
-            print("step", count, "=>", queue)
             count += 1
             next_queue = deque()
             for pos in queue:
diff --git a/intcode.py b/intcode.py
index 63c14a8..804e296 100644
--- a/intcode.py
+++ b/intcode.py
@@ -1,6 +1,6 @@
 import threading
 from collections import defaultdict
-from queue import Queue
+from queue import Queue, Empty
 from enum import Enum
 from typing import List
 
@@ -9,13 +9,7 @@ class IntCodeState(Enum):
     INITIALIZED = 0
     RUNNING = 1
     HALTED = 2
-
-
-def _get_from_queue(queue: Queue, count: int = 1, timeout: int = 10) -> int | List[int] | None:
-    if count == 1:
-        return queue.get(timeout=timeout)
-    else:
-        return [queue.get(timeout=timeout) for _ in range(count)]
+    STOPPED = 3
 
 
 class IntCode(threading.Thread):
@@ -34,8 +28,6 @@ class IntCode(threading.Thread):
         return int(self.memory[address])
 
     def setMemoryValue(self, address: int, value: int):
-        if not isinstance(value, int):
-            print("Something set", value, "at", address, "and that's not int, but", value.__class__.__name__)
         self.memory[address] = value
 
     def getParameterValue(self, address: int, mode: int = 0) -> int:
@@ -58,6 +50,21 @@ class IntCode(threading.Thread):
     def isHalted(self):
         return self.state == IntCodeState.HALTED
 
+    def isStopped(self):
+        return self.state == IntCodeState.STOPPED
+
+    def _get_from_queue(self, queue: Queue, count: int = 1, timeout: int = 3) -> int | List[int] | None:
+        try:
+            if count == 1:
+                return queue.get(timeout=timeout)
+            else:
+                return [queue.get(timeout=timeout) for _ in range(count)]
+        except Empty as e:
+            if self.state == IntCodeState.STOPPED:
+                return None
+            else:
+                raise e
+
     def addInput(self, value: int):
         self.input_queue.put(value)
 
@@ -67,15 +74,18 @@ class IntCode(threading.Thread):
     def hasOutput(self):
         return self.output_queue.qsize() > 0
 
-    def getOutput(self, count: int = 1, timeout: int = 10) -> int | List[int] | None:
-        return _get_from_queue(self.output_queue, count, timeout)
+    def getOutput(self, count: int = 1, timeout: int = 3) -> int | List[int] | None:
+        return self._get_from_queue(self.output_queue, count, timeout)
 
-    def getInput(self, count: int = 1, timeout: int = 10) -> int | List[int] | None:
-        return _get_from_queue(self.input_queue, count, timeout)
+    def getInput(self, count: int = 1, timeout: int = 3) -> int | List[int] | None:
+        return self._get_from_queue(self.input_queue, count, timeout)
+
+    def stop(self):
+        self.state = IntCodeState.STOPPED
 
     def run(self):
         self.state = IntCodeState.RUNNING
-        while not self.isHalted():
+        while not self.isHalted() and not self.isStopped():
             instr = self.getMemoryValue(self.instr_ptr)
             op_code = instr % 100
             p1_mode = instr // 100 % 10