From fceb4ffa4219a8916ff9dbdb6108be6db8961d02 Mon Sep 17 00:00:00 2001
From: alexion <contact@alexion.dev>
Date: Thu, 17 Sep 2026 13:22:11 -0400
Subject: [PATCH] feat(xatu): collect Nix source files

---
 Cargo.lock            |  1 +
 src/xatu/BUILD        |  1 +
 src/xatu/Cargo.toml   |  1 +
 src/xatu/xatu.rs      | 16 ++++++---
 src/xatu/xatu_main.rs | 77 +++++++++++++++++++++++++++++++++++++++++--
 5 files changed, 89 insertions(+), 7 deletions(-)

diff --git a/Cargo.lock b/Cargo.lock
index f469377..7db0b5b 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -256,6 +256,7 @@ name = "xatu"
 version = "0.1.0"
 dependencies = [
  "clap",
+ "monorepo",
 ]
 
 [[package]]
diff --git a/src/xatu/BUILD b/src/xatu/BUILD
index 235452b..7eb3699 100644
--- a/src/xatu/BUILD
+++ b/src/xatu/BUILD
@@ -12,6 +12,7 @@ rust_binary(
     srcs = ["xatu_main.rs"],
     deps = [
         ":xatu_lib",
+        "//src/monorepo:monorepo",
         "//third_party/crates:clap",
     ],
 )
diff --git a/src/xatu/Cargo.toml b/src/xatu/Cargo.toml
index 35b9fb0..aa1d37b 100644
--- a/src/xatu/Cargo.toml
+++ b/src/xatu/Cargo.toml
@@ -12,3 +12,4 @@ path = "xatu_main.rs"
 
 [dependencies]
 clap = { workspace = true, features = ["derive"] }
+monorepo = { workspace = true }
diff --git a/src/xatu/xatu.rs b/src/xatu/xatu.rs
index 1e67e84..ac8d3a5 100644
--- a/src/xatu/xatu.rs
+++ b/src/xatu/xatu.rs
@@ -1,8 +1,16 @@
-pub fn run() -> Result<()> {
+use std::path::PathBuf;
+
+pub fn run(files: Vec<SourceFile>) -> Result<()> {
+    for file in files {
+        println!("{}", file.path.display());
+    }
     Ok(())
 }
 
-pub type Result<T> = std::result::Result<T, Error>;
+pub type Result<T> = std::result::Result<T, std::io::Error>;
 
-#[derive(Debug, PartialEq, Eq)]
-pub enum Error {}
+#[derive(Debug)]
+pub struct SourceFile {
+    pub path: PathBuf,
+    pub source: String,
+}
diff --git a/src/xatu/xatu_main.rs b/src/xatu/xatu_main.rs
index 28b0a58..567dfe1 100644
--- a/src/xatu/xatu_main.rs
+++ b/src/xatu/xatu_main.rs
@@ -1,9 +1,80 @@
 use clap::Parser;
+use std::path::{Path, PathBuf};
+use xatu::SourceFile;
+
+fn is_nix_file(path: &Path) -> bool {
+    path.extension().is_some_and(|extension| extension == "nix")
+}
+
+// TODO: Add configurable exclusions.
+fn is_excluded_dir(path: &Path) -> bool {
+    path.file_name()
+        .and_then(|name| name.to_str())
+        .is_some_and(|name| {
+            matches!(
+                name,
+                ".git"
+                    | "bazel-bin"
+                    | "bazel-dev"
+                    | "bazel-out"
+                    | "bazel-testlogs"
+                    | "target"
+                    | "third_party"
+            ) || name == "result"
+                || name.starts_with("result-")
+        })
+}
+
+fn collect_source_files(path: &Path) -> xatu::Result<Vec<SourceFile>> {
+    let metadata = std::fs::symlink_metadata(path)?;
+
+    if metadata.file_type().is_dir() {
+        if is_excluded_dir(path) {
+            return Ok(Vec::new());
+        }
+
+        let mut files = Vec::new();
+
+        for entry in std::fs::read_dir(path)? {
+            let entry = entry?;
+            files.extend(collect_source_files(&entry.path())?);
+        }
+
+        return Ok(files);
+    }
+
+    if metadata.file_type().is_file() && is_nix_file(path) {
+        return Ok(vec![SourceFile {
+            path: path.to_path_buf(),
+            source: std::fs::read_to_string(path)?,
+        }]);
+    }
+
+    Ok(Vec::new())
+}
 
 #[derive(Debug, Parser)]
-struct Args {}
+struct Args {
+    #[arg(value_name = "PATH", default_value = ".")]
+    paths: Vec<PathBuf>,
+}
 
 fn main() -> xatu::Result<()> {
-    let Args {} = Args::parse();
-    xatu::run()
+    let args = Args::parse();
+
+    let paths: Vec<PathBuf> = args
+        .paths
+        .into_iter()
+        .map(monorepo::workspace::resolve_workspace_path)
+        .collect();
+
+    let files: Vec<SourceFile> = paths
+        .iter()
+        .map(|path| collect_source_files(path))
+        .collect::<xatu::Result<Vec<_>>>()?
+        .into_iter()
+        .flatten()
+        .collect();
+
+    xatu::run(files)
 }