From 1ea592b42e879b1ad5985d7b951237ea7f636e58 Mon Sep 17 00:00:00 2001
From: aaron <aaron@duckpond.ch>
Date: Thu, 8 Dec 2022 00:15:32 +0100
Subject: [PATCH] kind of solve part a

---
 7/nospaceleft.py | 56 +++++++++++++++++++++++++++++++++---------------
 1 file changed, 39 insertions(+), 17 deletions(-)

diff --git a/7/nospaceleft.py b/7/nospaceleft.py
index 95f7da7..2b75ca6 100644
--- a/7/nospaceleft.py
+++ b/7/nospaceleft.py
@@ -1,36 +1,58 @@
+from collections import defaultdict
+
 from aocd.models import Puzzle
 from aocd import submit
 
 
-def get_size(commands: list, dirs: list, size: int) -> int:
+def get_sizes(dirs: dict, max_size: int) -> int:
     """
-    parse tree structure and get size of all files > size
+    gather all filesizes from the input
     """
-    print(commands)
-    print(dirs)
-    print(size)
+    filtered_dirs = [ value for value in dirs.values() if value < max_size]
+    return sum(filtered_dirs)
 
-    return 0
-
-
-def parse_input(data: str) -> (list,list):
+def parse_input(input_str: str) -> list:
     """
-    parse input data
+    the input string consists of the following four message types
+    - $ cd ..               -> pop dir name from stack
+    - $ cd [dir]            -> push dir name to stack
+    - $ ls                  -> ignore
+    - dir [dir]             -> ignore
+    - [size] [file]         -> sum up the sizes of all files in this dir
+    parsing is done by implementing a state machine which gathers all
+    available information in the following dictionary.
+    - {list['/','dir','path']:int(size_sum)}
     """
-    return ([],[])
-
+    path = []
+    dirs = defaultdict(int)
+    for line in input_str.splitlines():
+        match line.split():
+            case ('$', 'cd', '..'):
+                path.pop()
+            case ('$', 'cd', name):
+                path.append(name)
+            case ('$', 'ls'):
+                continue
+            case ('dir', _):
+                continue
+            case (size, file):
+                size = int(size)
+                for i in range(len(path)):
+                    key = tuple(path[:i+1]) # list not hashable
+                    dirs[key] += size
+    return dirs
 
 if __name__ == "__main__":
     # get puzzle and parse data
     puzzle = Puzzle(year=2022, day=7)
-    commands, dirs = parse_input(puzzle.input_data)
+    dirs = parse_input(puzzle.input_data)
 
-    # part a:
-    answer_a = get_size(commands, dirs, 1000)
+    # part a: get the sum of all dirs where the size is at most 100k
+    answer_a = get_sizes(dirs, 100000)
     print(f"{answer_a}")
-    #submit(answer_a, part="a", day=7, year=2022)
+    submit(answer_a, part="a", day=7, year=2022)
 
     # part b:
-    answer_b = get_size(commands, dirs, 10000)
+    answer_b = get_sizes(dirs, 100)
     print(f"{answer_b}")
     #submit(answer_b, part="b", day=7, year=2022)