From b3c49e5353e3911aed20aef1a267643d3f9f14f8 Mon Sep 17 00:00:00 2001
From: Stefan Harmuth <stefan.harmuth@docomodigital.com>
Date: Sat, 12 Dec 2020 11:20:30 +0100
Subject: [PATCH] day12: it's a little bit slower, but I like the cleaner code

---
 day12.py | 104 ++++++++++++++++++++++++++-----------------------------
 1 file changed, 50 insertions(+), 54 deletions(-)

diff --git a/day12.py b/day12.py
index 1acd333..9b0cdc4 100644
--- a/day12.py
+++ b/day12.py
@@ -6,73 +6,69 @@ TEST_SOLUTION_PART2 = 286
 FACING = ['N', 'E', 'S', 'W']
 
 
-def move(instruction, posX, posY, facing):
-    where = instruction[0]
-    dist = int(instruction[1:])
+class Ship:
+    def __init__(self, waypoint_mode=False, posShipX=0, posShipY=0, posWaypointX=0, posWaypointY=0, facing=0):
+        self.pos = [
+            {
+                'x': posShipX,
+                'y': posShipY
+            },
+            {
+                'x': posWaypointX,
+                'y': posWaypointY
+            }
+        ]
+        self.waypoint_mode = waypoint_mode
+        self.facing = facing
 
-    if where == 'F':
-        where = FACING[facing]
+    def move(self, direction, distance):
+        if direction == 'F':
+            if self.waypoint_mode:
+                self.pos[0]['x'] += self.pos[1]['x'] * distance
+                self.pos[0]['y'] += self.pos[1]['y'] * distance
+                return
+            else:
+                direction = FACING[self.facing]
 
-    if where == 'N':
-        posY -= dist
-    elif where == 'S':
-        posY += dist
-    elif where == 'E':
-        posX += dist
-    elif where == 'W':
-        posX -= dist
-    elif where == 'R':
-        facing = (facing + int(dist / 90)) % 4
-    elif where == 'L':
-        facing = (facing - int(dist / 90)) % 4
+        if direction == 'N':
+            self.pos[self.waypoint_mode]['y'] -= distance
+        elif direction == 'S':
+            self.pos[self.waypoint_mode]['y'] += distance
+        elif direction == 'E':
+            self.pos[self.waypoint_mode]['x'] += distance
+        elif direction == 'W':
+            self.pos[self.waypoint_mode]['x'] -= distance
+        elif direction == 'R':
+            if not self.waypoint_mode:
+                self.facing = (self.facing + int(distance / 90)) % 4
+            else:
+                for i in range(int(distance / 90)):
+                    self.pos[1]['x'], self.pos[1]['y'] = -self.pos[1]['y'], self.pos[1]['x']
+        elif direction == 'L':
+            if not self.waypoint_mode:
+                self.facing = (self.facing - int(distance / 90)) % 4
+            else:
+                for i in range(int(distance / 90)):
+                    self.pos[1]['x'], self.pos[1]['x'] = self.pos[1]['y'], -self.pos[1]['x']
 
-    return posX, posY, facing
+    def getManhattanDistance(self, startX=0, startY=0):
+        return abs(self.pos[0]['x'] + startX) + abs(self.pos[0]['y'] + startY)
 
 
 def part1(test_mode=False):
     my_input = aoclib.getInputAsArray(day=DAY, test=test_mode)
 
-    posX = 0
-    posY = 0
-    face = 1
+    ship = Ship(facing=1)
     for instruction in my_input:
-        posX, posY, face = move(instruction, posX, posY, face)
+        ship.move(instruction[0], int(instruction[1:]))
 
-    return abs(posX) + abs(posY)
-
-
-def moveWaypoint(instruction, posShipX, posShipY, posWaypointX, posWaypointY):
-    where = instruction[0]
-    dist = int(instruction[1:])
-
-    if where == 'F':
-        posShipX += posWaypointX * dist
-        posShipY += posWaypointY * dist
-    elif where == 'N':
-        posWaypointY -= dist
-    elif where == 'S':
-        posWaypointY += dist
-    elif where == 'E':
-        posWaypointX += dist
-    elif where == 'W':
-        posWaypointX -= dist
-    elif where == 'R':
-        for i in range(int(dist / 90)):
-            posWaypointX, posWaypointY = -posWaypointY, posWaypointX
-    elif where == 'L':
-        for i in range(int(dist / 90)):
-            posWaypointX, posWaypointY = posWaypointY, -posWaypointX
-
-    return posShipX, posShipY, posWaypointX, posWaypointY
+    return ship.getManhattanDistance()
 
 
 def part2(test_mode=False):
     my_input = aoclib.getInputAsArray(day=DAY, test=test_mode)
-    posShipX = 0
-    posShipY = 0
-    posWaypointX = 10
-    posWaypointY = -1
+    ship = Ship(waypoint_mode=True, posWaypointX=10, posWaypointY=-1, facing=1)
     for instruction in my_input:
-        posShipX, posShipY, posWaypointX, posWaypointY = moveWaypoint(instruction, posShipX, posShipY, posWaypointX, posWaypointY)
+        ship.move(instruction[0], int(instruction[1:]))
 
-    return abs(posShipX) + abs(posShipY)
+    return ship.getManhattanDistance()