From 909320d2fbb1a287760998ec86fff399bd43f5ba Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Gon=C3=A7alo=20Val=C3=A9rio?= <gon@ovalerio.net>
Date: Sun, 1 Nov 2020 22:38:22 +0000
Subject: [PATCH] step fifteen: record hash of last commit to HEAD

---
 src/base.rs | 6 ++++--
 src/data.rs | 4 ++++
 2 files changed, 8 insertions(+), 2 deletions(-)

diff --git a/src/base.rs b/src/base.rs
index c5c00d2..f540be9 100644
--- a/src/base.rs
+++ b/src/base.rs
@@ -67,7 +67,9 @@ pub fn commit(message: &str) -> String {
     commit += "\n";
     commit += format!("{}\n", message).as_str();
 
-    return data::hash_object(&commit.into_bytes(), "commit".to_owned());
+    let oid = data::hash_object(&commit.into_bytes(), "commit".to_owned());
+    data::set_head(oid.clone());
+    return oid;
 }
 
 fn is_ignored(path: &String) -> bool {
@@ -112,7 +114,7 @@ fn get_tree(oid: String, base_path: String) -> HashMap<String, String> {
 }
 
 fn empty_current_directory(dir: &str) -> io::Result<()> {
-    // Delete current directory, less the ignored directories
+    // Delete current directory, except the ignored directories and files
     for entry in fs::read_dir(dir)? {
         let entry = entry?;
         let path = entry.path();
diff --git a/src/data.rs b/src/data.rs
index ea9d174..336e9a3 100644
--- a/src/data.rs
+++ b/src/data.rs
@@ -41,3 +41,7 @@ pub fn get_object(hash: String, expected: String) -> String {
 
     return data;
 }
+
+pub fn set_head(oid: String) {
+    fs::write(format!("{}/HEAD", RGIT_DIR), oid).expect("Failed to updated HEAD");
+}