#!/usr/bin/env python

from collections import Counter

myinput = []

with open("/home/login/bin/advent/input7.txt", 'r') as f:
	for line in f:
		myinput.append(line[:-1]) #no newlines in myinput

def stripChar(text):
	if text[0]=='(' and text[-1]==')':
		return text[1:-1]
	elif text[-1]==',':
		return text[:-1]
	else:
		return text

mysecondfinalinput = [line.split(" ") for line in myinput]
myfinalinput = [[stripChar(item) for item in line if item != '->'] for line in mysecondfinalinput]

my_parent = {}

for line in myfinalinput:
	for item in line:
		if line.index(item) < 2:
			continue
		else:
			my_parent[item] = {'name': line[0], 'weight': int(line[1])}

answer1 = ""

for line in myfinalinput:
	if line[0] not in my_parent:
		answer1 = line[0]
		break

print("Part 1: " + answer1)

self_weights = {}

def self_weight(text):
 	global self_weights
 	if text in self_weights:
 		return self_weights[text]
	else:
		index = [line[0] for line in myfinalinput].index(text)
		self_weights[text] = int(myfinalinput[index][1])
		return int(myfinalinput[index][1])

my_children = {}

for line in myfinalinput:
		my_children[line[0]] = list(map(lambda x: {'name': x, 'weight': self_weight(x)}, line[2:]))

answer2 = 0

total_weight_carried = {}

def total_weight(node_name):
	global total_weight_carried

	my_weight = self_weight(node_name)

	if node_name not in my_children:
		return my_weight
	elif node_name in total_weight_carried:
		return my_weight + total_weight_carried[node_name]
	else:
		children = my_children[node_name]
		children_total_weight = 0
		for child in children:
			child_self_weight = child['weight']
			child_total_weight = total_weight(child['name'])
			children_total_weight += child_total_weight
			total_weight_carried[child['name']] = child_total_weight - child_self_weight
		return my_weight + children_total_weight

def sibling_name(node_name):
	siblings_incl_self = my_children[my_parent[node_name]['name']]
	for sibling in siblings_incl_self:
		if sibling['name'] == node_name:
			continue
		else:
			return sibling['name']

# Assumption: only one wrong-weighted node
def return_corrected_weight(node_name):
	if node_name not in my_children:
		#My parent has leaf-nodes for children.
	    #I have no carried weight, so self-weight must be unequal to sibling self-weights.
		return (node_name, self_weight(node_name), self_weight(node_name) - abs(self_weight(node_name)-sibling_weight(node_name)))
	else:
		children = my_children[node_name]
		children_props = {'total_weights': [total_weight(child['name']) for child in children], 'names': [child['name'] for child in children]}
		if len(set(children_props['total_weights']))==1: #I carry balanced children, so my self-weight must be problematic.
			return (node_name, "Old weight: " + str(self_weight(node_name)), "New weight: " + str(self_weight(node_name) - abs(total_weight(node_name)-total_weight(sibling_name(node_name)))))
		else:
			counter = Counter(children_props['total_weights'])
			unbalanced_node_name = children_props['names'][children_props['total_weights'].index(min(counter, key=counter.get))]
			return return_corrected_weight(unbalanced_node_name)


answer2 = return_corrected_weight(answer1)

print("Part 2: " + str(answer2))