1 files changed, 53 insertions, 0 deletions
diff --git a/src/fs.rs b/src/fs.rs
new file mode 100644
index 0000000..cb8ce66
--- /dev/null
+++ b/src/fs.rs
@@ -0,0 +1,53 @@
+//! Provides the module used for filesystem operations made by this library.
+
+use std::path::Path;
+
+use crate::{hasher::Hasher, node::Node};
+
+/// Reads the entire content of a file into a `Vec<u8>`.
+///
+/// If the file cannot be read, an error message is printed to stderr, and the program exits.
+///
+/// `path` is a reference to a `String` representing the path to the file.
+fn read_file_content(path: &String) -> Vec<u8> {
+    match std::fs::read(path) {
+        Ok(contents) => contents,
+        Err(e) => {
+            eprintln!("Failed to read file '{}': {}", path, e);
+            std::process::exit(1);
+        }
+    }
+}
+
+/// Recursively hashes the contents of files and directories.
+///
+/// This function iterates through a list of filenames. For each file, it reads its content,
+/// hashes it using the provided `Hasher`, and creates a leaf `Node`. If an entry is a directory,
+/// it recursively calls itself to hash the directory's contents and extends the current
+/// list of nodes with the results.
+pub fn hash_dir<H>(hasher: H, filenames: Vec<String>) -> Vec<Node>
+where
+    H: Hasher + 'static + std::marker::Sync + Clone,
+{
+    let mut nodes: Vec<Node> = vec![];
+    for filename in &filenames {
+        let file = Path::new(filename);
+        if file.is_file() {
+            let hash = hasher.hash(read_file_content(filename).as_slice());
+
+            nodes.push(Node::new_leaf(hash));
+        } else if file.is_dir() {
+            let mut filenames_in_dir: Vec<String> = file
+                .read_dir()
+                .unwrap()
+                .map(|entry| String::from(entry.unwrap().path().to_str().unwrap()))
+                .collect();
+
+            filenames_in_dir.sort();
+
+            nodes.extend(hash_dir(hasher.clone(), filenames_in_dir));
+        }
+    }
+
+    nodes
+}