package vcs

import (
	"fmt"
	"os"
	"path/filepath"
)

// IsPijulRepo checks if the given path contains a Pijul repository.
func IsPijulRepo(path string) bool {
	info, err := os.Stat(filepath.Join(path, ".pijul"))
	if err != nil {
		return false
	}
	return info.IsDir()
}

// IsGitRepo checks if the given path contains a Git repository.
func IsGitRepo(path string) bool {
	info, err := os.Stat(filepath.Join(path, ".git"))
	if err != nil {
		// Also check for bare git repos (HEAD file at top level).
		if _, err := os.Stat(filepath.Join(path, "HEAD")); err == nil {
			return true
		}
		return false
	}
	return info.IsDir()
}

// DetectVCS detects whether a path contains a Git or Pijul repository.
func DetectVCS(path string) (string, error) {
	if IsPijulRepo(path) {
		return "pijul", nil
	}
	if IsGitRepo(path) {
		return "git", nil
	}
	return "", fmt.Errorf("no VCS repository found at %s", path)
}