From 1dcdb86bedf9e6371945812d54369108d4fbb4ec Mon Sep 17 00:00:00 2001
From: Kristofers Solo <dev@kristofers.xyz>
Date: Mon, 1 Dec 2025 19:16:34 +0200
Subject: [PATCH] Finish part-1

---
 2025/daily-template/src/part1.rs |  2 +
 2025/daily-template/src/part2.rs |  2 +
 2025/day-01/src/part1.rs         | 95 ++++++++++++++++++++++++++++++--
 3 files changed, 94 insertions(+), 5 deletions(-)

diff --git a/2025/daily-template/src/part1.rs b/2025/daily-template/src/part1.rs
index 94144f7..0a00e1f 100644
--- a/2025/daily-template/src/part1.rs
+++ b/2025/daily-template/src/part1.rs
@@ -1,6 +1,8 @@
 use miette::Result;
 
 #[tracing::instrument]
+#[allow(clippy::missing_panics_doc)]
+#[allow(clippy::missing_errors_doc)]
 pub fn process(input: &str) -> Result<usize> {
     todo!("day xx - part 1");
     Ok(0)
diff --git a/2025/daily-template/src/part2.rs b/2025/daily-template/src/part2.rs
index cbcdee4..ede34a7 100644
--- a/2025/daily-template/src/part2.rs
+++ b/2025/daily-template/src/part2.rs
@@ -1,6 +1,8 @@
 use miette::Result;
 
 #[tracing::instrument]
+#[allow(clippy::missing_panics_doc)]
+#[allow(clippy::missing_errors_doc)]
 pub fn process(input: &str) -> Result<usize> {
     todo!("day xx - part 2");
     Ok(0)
diff --git a/2025/day-01/src/part1.rs b/2025/day-01/src/part1.rs
index 94144f7..b23a885 100644
--- a/2025/day-01/src/part1.rs
+++ b/2025/day-01/src/part1.rs
@@ -1,9 +1,85 @@
 use miette::Result;
+use std::str::FromStr;
+
+#[derive(Debug, Clone, Copy, PartialEq)]
+enum Direction {
+    Left,
+    Right,
+}
+
+impl FromStr for Direction {
+    type Err = String;
+    fn from_str(s: &str) -> std::result::Result<Self, Self::Err> {
+        match s.to_lowercase().trim() {
+            "l" => Ok(Self::Left),
+            "r" => Ok(Self::Right),
+            _ => Err("Wrong value".to_string()),
+        }
+    }
+}
+
+#[derive(Debug, Clone, Copy)]
+struct Rotation {
+    amount: i32,
+    direction: Direction,
+}
+
+impl Rotation {
+    const fn right(self, dial: i32) -> i32 {
+        (dial + self.amount).rem_euclid(100)
+    }
+
+    const fn left(self, dial: i32) -> i32 {
+        (dial - self.amount).rem_euclid(100)
+    }
+}
+
+impl FromStr for Rotation {
+    type Err = String;
+    fn from_str(s: &str) -> std::result::Result<Self, Self::Err> {
+        let trimmed = s.trim();
+        let (direction_str, amount_str) = trimmed.split_at(1);
+        let direction = direction_str.parse()?;
+        let amount = amount_str.parse::<i32>().map_err(|e| e.to_string())?;
+
+        Ok(Self { amount, direction })
+    }
+}
+
+#[derive(Debug, Clone)]
+struct Sequence {
+    rotations: Vec<Rotation>,
+}
+
+impl FromStr for Sequence {
+    type Err = String;
+    fn from_str(s: &str) -> std::result::Result<Self, Self::Err> {
+        let rotations = s
+            .trim()
+            .lines()
+            .map(|line| line.parse::<Rotation>().unwrap())
+            .collect::<Vec<_>>();
+        Ok(Self { rotations })
+    }
+}
 
 #[tracing::instrument]
+#[allow(clippy::missing_panics_doc)]
+#[allow(clippy::missing_errors_doc)]
 pub fn process(input: &str) -> Result<usize> {
-    todo!("day xx - part 1");
-    Ok(0)
+    let sequence = input.parse::<Sequence>().unwrap();
+    let mut count = 0;
+    sequence.rotations.iter().fold(50, |acc, rotation| {
+        let number = match rotation.direction {
+            Direction::Left => rotation.left(acc),
+            Direction::Right => rotation.right(acc),
+        };
+        if number == 0 {
+            count += 1;
+        }
+        number
+    });
+    Ok(count)
 }
 
 #[cfg(test)]
@@ -12,9 +88,18 @@ mod tests {
 
     #[test]
     fn test_process() -> Result<()> {
-        let input = "";
-        todo!("haven't built test yet");
-        let result = 0;
+        let input = "L68
+L30
+R48
+L5
+R60
+L55
+L1
+L99
+R14
+L82
+";
+        let result = 3;
         assert_eq!(process(input)?, result);
         Ok(())
     }