package vfs

import (
	"fmt"
	"io/fs"
	"os"
	"sync"
)

type directory struct {
	name     string
	mode     os.FileMode
	children map[string]interface{}
	mutex    sync.Mutex
}

type directoryHandle struct {
	dir *directory
	idx int
}

func (d *directoryHandle) Stat() (fs.FileInfo, error) {
	sz, err := d.dir.Size()
	if err != nil {
		return nil, err
	}

	return &fileInfo{
		name: d.dir.name,
		size: sz,
		mode: d.dir.mode | fs.ModeDir,
	}, nil
}

func (d *directoryHandle) Read(data []byte) (int, error) {
	return 0, fmt.Errorf("%s is a directory", d.dir.name)
}

func (d *directoryHandle) Close() error {
	return nil
}

func (d *directory) Size() (int64, error) {
	sum := int64(0)
	for _, e := range d.children {
		switch v := e.(type) {
		case *directory:
			dir := v
			sz, err := dir.Size()
			if err != nil {
				return 0, err
			}
			sum += sz

		case *MockFile:
			f := v
			f.open = true
			stat, err := f.Stat()
			if err != nil {
				return 0, err
			}
			sum += stat.Size()
			f.open = false

		case *File:
			f := v
			f.open = true
			stat, err := f.Stat()
			if err != nil {
				return 0, err
			}
			sum += stat.Size()
			f.open = false
		}
	}
	return sum, nil
}