package path

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

// PathProjectRoot searches upwards from the current directory to find the project root,
// identified by the presence of a "go.mod" file.
func PathProjectRoot() (string, error) {
	dir, err := os.Getwd()
	if err != nil {
		return "", err
	}

	for {
		if _, err := os.Stat(filepath.Join(dir, "go.mod")); err == nil {
			return dir, nil
		}
		if _, err := os.Stat(filepath.Join(dir, "go.work")); err == nil {
			return dir, nil
		}
		if fi, err := os.Stat(filepath.Join(dir, ".git")); err == nil && fi.IsDir() {
			return dir, nil
		}

		parent := filepath.Dir(dir)
		if parent == dir {
			return "", errors.New("go.mod not found in any parent directory")
		}
		dir = parent
	}
}