4 files changed, 50 insertions, 0 deletions

diff --git a/README.md b/README.md
new file mode 100644
index 0000000..b9b7158
--- /dev/null
+++ b/README.md
@@ -0,0 +1,11 @@
+### Grit
+*NOT FINISHED YET*
+
+An attempt to implement a git client... in Rust, so that I can say "I use Rust btw".
+
+- Install rust and cargo
+- `cargo run -- [ARGS]` to test in dev mode
+  
+`ARGS` is supposedly partially compatible with git commands.
+
+For now the only sub-command that works properly is `init`
diff --git a/src/main.rs b/src/main.rs
index 66891c4..a82a6e8 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -5,6 +5,7 @@ mod object;
 use crate::repository::GitRepository;
 use clap::{Parser, Subcommand};
 use std::path::PathBuf;
+use crate::object::{GitObject, GitObjectType};
 
 #[derive(Parser)]
 #[command(version, about, long_about = None)]
@@ -69,6 +70,19 @@ fn main() {
             }
             GitRepository::create_new_repo(p);
         }
+        Command::CatFile { object_type, sha} => {
+            // todo detect root otomatis
+            // temporary
+            let repo = GitRepository::from_dir(PathBuf::from("."));
+            let object_type = match &object_type[..] {
+                "blob" => GitObjectType::Blob,
+                "commit" => GitObjectType::Commit,
+                "tag" => GitObjectType::Tag,
+                "tree" => GitObjectType::Tree,
+                _ => GitObjectType::Undefined
+            };
+            repo.cat_file(object_type, sha.as_str());
+        }
         _ => {}
     }
 }
\ No newline at end of file
diff --git a/src/object.rs b/src/object.rs
index 12f83ae..8877641 100644
--- a/src/object.rs
+++ b/src/object.rs
@@ -1,3 +1,4 @@
+use std::fmt::{Display, Formatter};
 use crate::utilities::{deserialize_kv_with_message, serialize_kv_with_message};
 use crate::{create_path_or_die, die};
 use derive_is_enum_variant::is_enum_variant;
@@ -143,4 +144,15 @@ impl GitCommit {
     pub fn serialize(&self) -> Vec<u8> {
         serialize_kv_with_message(&self.header, self.message.as_str())
     }
+}
+
+impl Display for GitCommit {
+    fn fmt(&self, f: &mut Formatter<'_>) -> std::fmt::Result {
+        for (k, v) in self.header {
+            write!(f, "{} {}\n", k, v)?;
+        }
+        write!(f, "\n")?;
+        write!(f, "{}", self.message)?;
+        Ok(())
+    }
 }
\ No newline at end of file
diff --git a/src/repository.rs b/src/repository.rs
index f5ecffb..97b7816 100644
--- a/src/repository.rs
+++ b/src/repository.rs
@@ -5,6 +5,7 @@ use ini::ini;
 use std::collections::HashMap;
 use std::io::Write;
 use std::path::PathBuf;
+use crate::object::{GitCommit, GitObject, GitObjectType};
 
 pub struct GitRepository {
     pub worktree: PathBuf,
@@ -70,4 +71,16 @@ impl GitRepository {
         }
         println!("Git repository initialized in {}", repo.worktree.display());
     }
+
+    pub fn cat_file(&self, object_type: GitObjectType, sha: &str) {
+        match object_type {
+            GitObjectType::Commit => {
+                let path = self.gitdir.join(&sha[..2]).join(&sha[2..]);
+                let git_object = GitObject::from_file(path);
+                let git_commit = GitCommit::from_git_object(git_object);
+                println!("{}", git_commit);
+            }
+            _ => {}
+        }
+    }
 }
\ No newline at end of file