auto grab input & day 5

.gitignore

@@ -1,9 +1,10 @@
 # temporary files
 /target
+/input
+session.txt
 
 # secrets
 .env
 
-# don't include inputs
+# editors
-/input
+.vscode
-session.txt

Cargo.lock

@@ -12,7 +12,7 @@ dependencies = [
 ]
 
 [[package]]
-name = "aoc-2022"
+name = "aoc"
 version = "0.1.0"
 dependencies = [
  "eyes",

Cargo.toml

@@ -1,5 +1,5 @@
 [package]
-name = "aoc-2022"
+name = "aoc"
 version = "0.1.0"
 edition = "2021"
 
@@ -8,6 +8,4 @@ regex = "1"
 itertools = "0.10"
 rayon = "1"
 eyes = "1"
-
-[build-dependencies]
 reqwest = { version = "0.11", features = ["blocking", "cookies"] }

build.rs

@@ -1,39 +0,0 @@
-use reqwest::{blocking::Client, cookie::Jar};
-use std::{collections::HashMap, env, fs, path::PathBuf, sync::Arc};
-
-const BASE_URL: &str = "https://adventofcode.com";
-const YEAR: &str = "2022";
-
-fn main() {
-    // get env and dotenv into hashmap
-    let file = fs::read_to_string(".env").unwrap_or(String::new());
-    let env = file
-        .lines()
-        .filter_map(|line| line.split_once('='))
-        .map(|(key, value)| (key.to_string(), value.to_string()))
-        .chain(env::vars())
-        .collect::<HashMap<_, _>>();
-
-    // create session cookie
-    let session = env
-        .get("SESSION")
-        .expect("SESSION environment variable not set, retrieve it from https://adventofcode.com");
-    let cookie = format!("session={session}");
-
-    // setup client
-    let jar = Arc::new(Jar::default());
-    jar.add_cookie_str(&cookie, &BASE_URL.parse().unwrap());
-    let client = Client::builder().cookie_provider(jar).build().unwrap();
-
-    // download until day fails
-    for day in 1..=25 {
-        let path = PathBuf::from(format!("input/day{day}.txt"));
-        if path.try_exists().is_err() {
-            let url = format!("{BASE_URL}/{YEAR}/day/{day}/input");
-            let Ok(res) = client.get(url).send() else {
-                break
-            };
-            fs::write(path, res.text().unwrap()).unwrap();
-        }
-    }
-}

src/bin/2022-1.rs

@@ -1,7 +1,7 @@
 use itertools::Itertools;
 
 fn main() {
-    let input = std::fs::read_to_string("input/day1.txt").unwrap();
+    let input = aoc::input!();
     println!("part 1: {}", part1(&input));
     println!("part 1: {}", part2(&input));
 }

src/bin/2022-2.rs

@@ -1,7 +1,7 @@
 use eyes::parse;
 
 fn main() {
-    let input = std::fs::read_to_string("input/day2.txt").unwrap();
+    let input = aoc::input!();
     println!("part 1: {}", part1(&input));
     println!("part 1: {}", part2(&input));
 }

src/bin/2022-3.rs

@@ -2,7 +2,7 @@ use itertools::Itertools;
 use std::collections::HashSet;
 
 fn main() {
-    let input = std::fs::read_to_string("input/day3.txt").unwrap();
+    let input = aoc::input!();
     println!("part 1: {}", part1(&input));
     println!("part 1: {}", part2(&input));
 }

src/bin/2022-4.rs

@@ -1,7 +1,7 @@
 use eyes::parse;
 
 fn main() {
-    let input = std::fs::read_to_string("input/day4.txt").unwrap();
+    let input = aoc::input!();
     println!("part 1: {}", part1(&input));
     println!("part 1: {}", part2(&input));
 }

src/bin/2022-5.rs

@@ -0,0 +1,109 @@
+use eyes::parse;
+use itertools::Itertools;
+
+fn main() {
+    let input = aoc::input!();
+    println!("part 1: {}", part1(&input));
+    println!("part 1: {}", part2(&input));
+}
+
+fn part1(input: &str) -> String {
+    // parsing challenge..... yay......
+    let (crates, instructions) = input.split_once("\n\n").unwrap();
+    let mut stacks = crates
+        .lines()
+        .rev()
+        .skip(1)
+        .map(|line| {
+            line.chars()
+                .chunks(4)
+                .into_iter()
+                .map(|mut cr| (cr.next() == Some('[')).then(|| cr.next().unwrap()))
+                .collect::<Vec<_>>()
+        })
+        .fold(vec![vec![]; 9], |mut stacks, crates| {
+            for (i, c) in crates.into_iter().enumerate() {
+                if let Some(c) = c {
+                    stacks[i].push(c)
+                }
+            }
+            stacks
+        });
+
+    // perform instructions
+    instructions
+        .lines()
+        .map(|line| parse!(line, "move {} from {} to {}", usize, usize, usize))
+        .for_each(|(n, from, to)| {
+            (0..n).for_each(|_| {
+                if let Some(c) = stacks[from - 1].pop() {
+                    stacks[to - 1].push(c)
+                }
+            })
+        });
+
+    // get message
+    stacks
+        .into_iter()
+        .filter_map(|mut stack| stack.pop())
+        .collect::<String>()
+}
+
+fn part2(input: &str) -> String {
+    let (crates, instructions) = input.split_once("\n\n").unwrap();
+    let mut stacks = crates
+        .lines()
+        .rev()
+        .skip(1)
+        .map(|line| {
+            line.chars()
+                .chunks(4)
+                .into_iter()
+                .map(|mut cr| (cr.next() == Some('[')).then(|| cr.next().unwrap()))
+                .collect::<Vec<_>>()
+        })
+        .fold(vec![vec![]; 9], |mut stacks, crates| {
+            for (i, c) in crates.into_iter().enumerate() {
+                if let Some(c) = c {
+                    stacks[i].push(c)
+                }
+            }
+            stacks
+        });
+
+    // perform instructions
+    instructions
+        .lines()
+        .map(|line| parse!(line, "move {} from {} to {}", usize, usize, usize))
+        .for_each(|(n, from, to)| {
+            let len = stacks[from - 1].len();
+            let split = stacks[from - 1].split_off(len - n);
+            stacks[to - 1].extend(split);
+        });
+
+    // get message
+    stacks
+        .into_iter()
+        .filter_map(|mut stack| stack.pop())
+        .collect::<String>()
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn examples() {
+        let example = r#"    [D]    
+[N] [C]    
+[Z] [M] [P]
+ 1   2   3 
+
+move 1 from 2 to 1
+move 3 from 1 to 3
+move 2 from 2 to 1
+move 1 from 1 to 2"#;
+        assert_eq!(part1(example), "CMZ".to_string());
+        assert_eq!(part2(example), "MCD".to_string());
+    }
+}

src/lib.rs

@@ -1 +1,53 @@
+use reqwest::{blocking::Client, cookie::Jar};
+use std::{env, error::Error, fs, path::PathBuf, sync::Arc};
 
+const BASE_URL: &str = "https://adventofcode.com";
+
+#[macro_export]
+macro_rules! input {
+    () => {{
+        let stem = std::path::Path::new(file!())
+            .file_stem()
+            .unwrap()
+            .to_string_lossy();
+        let (year, day) = stem.split_once('-').unwrap();
+        $crate::get_day(year, day).unwrap()
+    }};
+}
+
+pub fn get_day(year: &str, day: &str) -> Result<String, Box<dyn Error>> {
+    let path = PathBuf::from(format!("input/{year}/day{day}.txt"));
+    fs::create_dir_all(path.parent().unwrap())?;
+
+    if let Ok(input) = fs::read_to_string(&path) {
+        Ok(input)
+    } else {
+        // get session token
+        let file = fs::read_to_string(".env").unwrap_or(String::new());
+        let session = file
+            .lines()
+            .filter_map(|line| line.split_once('='))
+            .map(|(key, value)| (key.to_string(), value.to_string()))
+            .chain(env::vars())
+            .find_map(|(k, v)| (k == "SESSION").then_some(v))
+            .ok_or(
+                "SESSION environment variable not set, retrieve it from https://adventofcode.com",
+            )?;
+
+        // create session cookie
+        let cookie = format!("session={session}");
+
+        // setup client
+        let jar = Arc::new(Jar::default());
+        jar.add_cookie_str(&cookie, &BASE_URL.parse()?);
+        let client = Client::builder().cookie_provider(jar).build()?;
+
+        // download until day fails
+        let url = format!("{BASE_URL}/{year}/day/{day}/input");
+        let text = client.get(url).send()?.text()?;
+        fs::create_dir_all(path.parent().unwrap())?;
+        fs::write(path, &text)?;
+
+        Ok(text)
+    }
+}