2 files changed, 197 insertions, 0 deletions
diff --git a/src/git_tools.rs b/src/git_tools.rs
new file mode 100644
index 0000000..1c361ca
--- /dev/null
+++ b/src/git_tools.rs
@@ -0,0 +1,106 @@
+use std::io::{Result, Error, ErrorKind};
+use std::process::Command;
+use std::path::Path;
+
+pub fn git_save_previous_branch(path: &Path) -> Result<String> {
+    let output = Command::new("git")
+        .arg("rev-parse")
+        .arg("--abbrev-ref")
+        .arg("HEAD")
+        .current_dir(path)
+        .output()?;
+    if !output.status.success() {
+        Err(Error::new(ErrorKind::Other, "Failed to get current branch"))
+    } else {
+        Ok(String::from_utf8(output.stdout).unwrap().trim().to_string())
+    }
+}
+
+pub fn git_checkout(path: &Path, branch: &str) -> Result<()> {
+    let output = Command::new("git")
+        .arg("checkout")
+        .arg(branch)
+        .current_dir(path)
+        .output()?;
+    if !output.status.success() {
+        Err(Error::new(ErrorKind::Other, format!("Failed to checkout {}", branch)))
+    } else {
+        Ok(())
+    }
+}
+
+pub fn git_fetch(path: &Path) -> Result<()> {
+    let output = Command::new("git")
+        .arg("fetch")
+        .current_dir(path)
+        .output()?;
+    if !output.status.success() {
+        return Err(Error::new(ErrorKind::Other, "Failed to fetch"));
+    }
+    Ok(())
+}
+
+pub fn git_check_for_conflicts(path: &Path) -> Result<bool> {
+    let merge_output = Command::new("git")
+        .arg("merge")
+        .arg("--no-commit")
+        .arg("--no-ff")
+        .arg("origin/main")
+        .current_dir(path)
+        .output()?;
+    if !merge_output.status.success() {
+        return Err(Error::new(ErrorKind::Other, "Failed to merge"));
+    }
+    let conflicts_output = Command::new("git")
+        .arg("ls-files")
+        .arg("--unmerged")
+        .current_dir(path)
+        .output()?;
+    Command::new("git")
+        .arg("merge")
+        .arg("--abort")
+        .current_dir(path)
+        .output()?;
+    Ok(!conflicts_output.stdout.is_empty())
+}
+
+pub fn git_merge(path: &Path) -> Result<()> {
+    let output = Command::new("git")
+        .arg("merge")
+        .arg("origin/main")
+        .current_dir(path)
+        .output()?;
+    if !output.status.success() {
+        Err(Error::new(ErrorKind::Other, "Failed to merge"))
+    } else {
+        Ok(())
+    }
+}
+
+pub fn git_push(path: &Path) -> Result<()> {
+    let output = Command::new("git")
+        .arg("push")
+        .arg("origin")
+        .arg("main")
+        .current_dir(path)
+        .output()?;
+    if !output.status.success() {
+        Err(Error::new(ErrorKind::Other, "Failed to push to origin"))
+    } else {
+        Ok(())
+    }
+}
+
+pub fn get_commit(path: &Path, revision: &str) -> Result<String> {
+    let output = Command::new("git")
+        .arg("rev-parse")
+        .arg("--short")
+        .arg(revision)
+        .current_dir(path)
+        .output()?;
+    if !output.status.success() {
+        Err(Error::new(ErrorKind::Other, "Failed to get current commit"))
+    } else {
+        Ok(String::from_utf8(output.stdout).unwrap().trim().to_string())
+    }
+}
diff --git a/src/main.rs b/src/main.rs
new file mode 100644
index 0000000..3b9caea
--- /dev/null
+++ b/src/main.rs
@@ -0,0 +1,91 @@
+mod git_tools;
+
+use std::env;
+use std::fs;
+use std::io::{Result, Error, ErrorKind};
+use std::path::Path;
+use std::process::exit;
+
+use git_tools::*;
+
+fn main() -> Result<()> {
+    if let Ok(cwd) = env::current_dir() {
+        if let Err(e) = scan_directories_to_synchronize(&cwd) {
+            eprintln!("Could not check directory for git repositories: {}", e);
+            exit(1);
+        }
+    } else {
+        eprintln!("Could not find current directory.");
+        exit(1);
+    }
+    Ok(())
+}
+
+fn scan_directories_to_synchronize(path: &Path) -> Result<()> {
+    let sync_ignore_file = path.join(".syncignore");
+    if sync_ignore_file.exists() {
+        return Ok(())
+    }
+    let git_directory = path.join(".git");
+    if git_directory.exists() {
+        if let Err(e) = synchronize_directory(&path) {
+            let relative_path = get_relative_path(path).unwrap();
+            eprintln!("Sync failed for {:?}. {}", relative_path, e);
+        }
+    } else {
+        for entry in fs::read_dir(path)? {
+            let path = entry?.path();
+            if path.is_dir() {
+                scan_directories_to_synchronize(&path)?;
+            }
+        }
+    }
+    Ok(())
+}
+
+fn synchronize_directory(path: &Path) -> Result<()> {
+    let previous_branch = git_save_previous_branch(path)?;
+    git_checkout(path, "main")?;
+    let result = attempt_synchronization(path);
+    git_checkout(path, &previous_branch)?;
+    result
+}
+
+fn attempt_synchronization(path: &Path) -> Result<()> {
+    let relative_path = get_relative_path(path).unwrap();
+    eprint!("{:?}. ", relative_path);
+    let previous_commit = get_commit(path, "HEAD")?;
+    git_fetch(path)?;
+    let remote_commit = get_commit(path, "origin/main")?;
+    if previous_commit == remote_commit {
+        eprintln!("Already up to date.");
+        return Ok(());
+    }
+    match git_check_for_conflicts(path) {
+        Ok(conflicts) => {
+            if !conflicts {
+                git_merge(path)?;
+                let new_commit = get_commit(path, "HEAD")?;
+                eprint!("Merged origin {:?}->{:?}. ", previous_commit, new_commit);
+                git_push(path)?;
+                eprintln!("Pushed.");
+            } else {
+                return Err(Error::new(ErrorKind::Other, "Conflicts detected"));
+            }
+        },
+        Err(e) => {
+            return Err(e);
+        }
+    }
+    Ok(())
+}
+
+// Path Helpers
+
+fn get_relative_path(path: &Path) -> Option<String> {
+    let cwd = env::current_dir().unwrap();
+    path.strip_prefix(cwd)
+        .ok()
+        .and_then(|p| p.to_str())
+        .map(|s| s.to_string())
+}