package main

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

type FileSystemNode struct {
	Name     string
	Path     string
	Format   string
	Children []*FileSystemNode
	Size     int64
	IsDir    bool
}

func main() {
	rootDirectory := BuildFileSystemTree("./files/")
	fmt.Println("root dir:", rootDirectory)
}

func BuildFileSystemTree(rootPath string) *FileSystemNode {
	fileInfo, err := os.Stat(rootPath)
	if err != nil {
		fmt.Printf("Error getting file info for %s: %v\n", rootPath, err)
		return nil
	}

	currentNode := &FileSystemNode{
		Name:  fileInfo.Name(),
		Path:  rootPath,
		IsDir: fileInfo.IsDir(),
		Size:  fileInfo.Size(),
	}

	if !currentNode.IsDir {
		textAfterLastPeriod := strings.Split(currentNode.Name, ".")
		if len(textAfterLastPeriod) > 1 {
			currentNode.Format = strings.ToUpper(textAfterLastPeriod[len(textAfterLastPeriod)-1])
		} else {
			currentNode.Format = "UNKNOWN"
		}
	}

	if currentNode.IsDir {
		dirEntries, err := os.ReadDir(rootPath)
		if err != nil {
			fmt.Printf("Error reading directory %s: %v\n", rootPath, err)
			return currentNode
		}

		for _, entry := range dirEntries {
			childPath := filepath.Join(rootPath, entry.Name())
			childNode := BuildFileSystemTree(childPath)
			if childNode != nil {
				currentNode.Children = append(currentNode.Children, childNode)
			}
		}
	}

	return currentNode
}