package adapters

import (
	"os"
	"path/filepath"
)

type LocalFsAdapter struct {
	root string
}

func (l LocalFsAdapter) readDir(path string) (FsResponse, error) {
	dirInfo, _ := os.Stat(path)

	entries, err := os.ReadDir(path)
	if err != nil {
		return FsResponse{}, err
	}

	out := make([]FsDirEntry, 0, len(entries))
	for _, e := range entries {
		info, _ := e.Info()

		entryType := "dir"
		if !e.IsDir() {
			entryType = contentTypeFor(e.Name())
		}

		out = append(out, FsDirEntry{
			Name:    e.Name(),
			Type:    entryType,
			ModTime: info.ModTime(),
		})
	}

	return FsResponse{
		Dir: &FsDir{
			Files:   out,
			Name:    ResponsePath(l.root, path),
			ModTime: dirInfo.ModTime(),
		},
	}, nil
}

func (l LocalFsAdapter) readFile(path string) (FsResponse, error) {
	fi, err := os.Stat(path)
	if err != nil {
		return FsResponse{}, err
	}

	data, err := os.ReadFile(path)
	if err != nil {
		return FsResponse{}, err
	}

	return FsResponse{
		File: &FsFile{
			Name:    ResponsePath(l.root, path),
			Type:    contentTypeFor(path),
			ModTime: fi.ModTime(),
			Content: data,
		},
	}, nil
}

func (l LocalFsAdapter) Read(path string) (FsResponse, error) {
	cleanRel, err := SafeRel(l.root, path)
	if err != nil {
		return FsResponse{}, err
	}
	target := filepath.Join(l.root, filepath.FromSlash(cleanRel))

	fi, err := os.Stat(target)
	if err != nil {
		if os.IsNotExist(err) {
			return FsResponse{}, ErrNotFound
		}

		return FsResponse{}, err
	}

	if fi.IsDir() {
		return l.readDir(target)
	}

	return l.readFile(target)
}

func (LocalFsAdapter) Write(path string, content []byte) error {
	return nil
}

func NewLocalFsAdapter(root string) (FileAdapter, error) {
	return LocalFsAdapter{
		root: root,
	}, nil
}