remove halting logic from day1

lib/aoc_runner.ex

@@ -1,15 +1,29 @@
 defmodule AOCRunner do
+  defp is_empty(s) do
+    (s |> String.trim() |> String.length()) == 0
+  end
+
   def run(advent) do
-    result = IO.stream() |> 
+    {_, state} = IO.stream() |>
     Enum.reduce_while(
-      advent.init_state(),
+      {nil, advent.init_state()},
       fn line, acc -> line
         |> advent.to_command()
-        |> advent.apply_command(acc)
-        |> then(fn acc -> if elem(acc, 2) do {:halt, acc} else {:cont, acc} end end)
+        |> then(fn command ->
+            {u, state} = acc
+            {u, advent.apply_command(command, state)}
+          end)
+        |> then(fn {u, s} ->
+            if (line |> is_empty()) && (u |> is_empty()) do
+              {:halt, {u, s}}
+            else
+              {:cont, {u, s}}
+            end
+          end)
+        |> then(fn {reduce_atom, {_, state}} -> {reduce_atom, {String.trim(line), state}} end)
       end
     )
 
-    IO.puts(advent.get_answer(result))
+    IO.puts(advent.get_answer(state))
   end
 end

lib/day1.ex

@@ -8,12 +8,12 @@ defmodule Day1 do
   end
 
   def get_answer(state) do
-    elem(state, 1) |> 
+    elem(state, 1) |>
       Enum.reduce(0, fn i, acc -> i + acc end)
   end
 
   def init_state() do
-    {nil, [0, 0, 0], false}
+    {nil, [0, 0, 0]}
   end
 
   def apply_command(command, state) do
@@ -24,24 +24,24 @@ defmodule Day1 do
   end
 
   defp apply_add(n, state) do
-    {current, total, exit} = state
-    new_current = if is_nil(current) do 0 else current end + n
+    {current, total} = state
+    new_current = n + if is_nil(current) do 0 else current end
     
-    {new_current, total, exit}
+    {new_current, total}
   end
 
   defp take_top_three(n, list) do
-    [ n | list ] |> 
+    [ n | list ] |>
       Enum.sort(:desc) |>
       Enum.take(3)
   end
 
   defp apply_reset(state) do
-    {current, total, exit} = state
-
-    case current do
-      nil -> {current, total, true}
-      _ -> {nil, take_top_three(current, total), exit}
+    {current, total} = state
+    if !is_nil(current) do
+      {nil, take_top_three(current, total)}
+    else
+      state
     end
   end
 end