filebrowser/directory/file.go

package directory

import (
	"encoding/json"
	"fmt"
	"io/ioutil"
	"net/http"
	"net/url"
	"os"
	"path"
	"path/filepath"
	"strings"
	"time"

	"github.com/dustin/go-humanize"
	"github.com/hacdias/caddy-filemanager/config"
	p "github.com/hacdias/caddy-filemanager/page"
	"github.com/hacdias/caddy-filemanager/utils/errors"
	"github.com/mholt/caddy/caddyhttp/httpserver"
)

// Info is the information about a particular file or directory
type Info struct {
	IsDir       bool
	Name        string
	Size        int64
	URL         string
	Path        string // The relative Path of the file/directory relative to Caddyfile.
	RootPath    string // The Path of the file/directory on http.FileSystem.
	ModTime     time.Time
	Mode        os.FileMode
	Mimetype    string
	Content     string
	Raw         []byte
	Type        string
	UserAllowed bool // Indicates if the user has permissions to open this directory
}

// GetInfo gets the file information and, in case of error, returns the
// respective HTTP error code
func GetInfo(url *url.URL, c *config.Config, u *config.User) (*Info, int, error) {
	var err error

	rootPath := strings.Replace(url.Path, c.BaseURL, "", 1)
	rootPath = strings.TrimPrefix(rootPath, "/")
	rootPath = "/" + rootPath

	relpath := u.PathScope + rootPath
	relpath = strings.Replace(relpath, "\\", "/", -1)
	relpath = filepath.Clean(relpath)

	file := &Info{
		URL:      url.Path,
		RootPath: rootPath,
		Path:     relpath,
	}
	f, err := u.Root.Open(rootPath)
	if err != nil {
		return file, errors.ToHTTPCode(err), err
	}
	defer f.Close()

	info, err := f.Stat()
	if err != nil {
		return file, errors.ToHTTPCode(err), err
	}

	file.IsDir = info.IsDir()
	file.ModTime = info.ModTime()
	file.Name = info.Name()
	file.Size = info.Size()
	return file, 0, nil
}

// GetExtendedInfo is used to get extra parameters for FileInfo struct
func (i *Info) GetExtendedInfo() error {
	err := i.Read()
	if err != nil {
		return err
	}

	i.Type = SimplifyMimeType(i.Mimetype)
	return nil
}

// Read is used to read a file and store its content
func (i *Info) Read() error {
	raw, err := ioutil.ReadFile(i.Path)
	if err != nil {
		return err
	}
	i.Mimetype = http.DetectContentType(raw)
	i.Content = string(raw)
	i.Raw = raw
	return nil
}

// HumanSize returns the size of the file as a human-readable string
// in IEC format (i.e. power of 2 or base 1024).
func (i Info) HumanSize() string {
	return humanize.IBytes(uint64(i.Size))
}

// HumanModTime returns the modified time of the file as a human-readable string.
func (i Info) HumanModTime(format string) string {
	return i.ModTime.Format(format)
}

// ServeAsHTML is used to serve single file pages
func (i *Info) ServeAsHTML(w http.ResponseWriter, r *http.Request, c *config.Config, u *config.User) (int, error) {
	if i.IsDir {
		return i.serveListing(w, r, c, u)
	}

	return i.serveSingleFile(w, r, c, u)
}

func (i *Info) serveSingleFile(w http.ResponseWriter, r *http.Request, c *config.Config, u *config.User) (int, error) {
	err := i.GetExtendedInfo()
	if err != nil {
		return errors.ToHTTPCode(err), err
	}

	if i.Type == "blob" {
		http.Redirect(w, r, c.AddrPath+r.URL.Path+"?download=true", http.StatusTemporaryRedirect)
		return 0, nil
	}

	page := &p.Page{
		Info: &p.Info{
			Name:   i.Name,
			Path:   i.RootPath,
			IsDir:  false,
			Data:   i,
			User:   u,
			Config: c,
		},
	}

	if CanBeEdited(i.Name) && u.AllowEdit {
		editor, err := i.GetEditor()

		if err != nil {
			return http.StatusInternalServerError, err
		}

		page.Info.Data = editor

		// TODO: if serve Single File finds an error while parsing, show the raw content to edit instead of giving 500
		return page.PrintAsHTML(w, "frontmatter", "editor")
	}

	return page.PrintAsHTML(w, "single")
}

func (i *Info) serveListing(w http.ResponseWriter, r *http.Request, c *config.Config, u *config.User) (int, error) {
	var err error

	file, err := u.Root.Open(i.RootPath)
	if err != nil {
		return errors.ToHTTPCode(err), err
	}
	defer file.Close()

	listing, err := i.loadDirectoryContents(file, r.URL.Path, u)
	if err != nil {
		fmt.Println(err)
		switch {
		case os.IsPermission(err):
			return http.StatusForbidden, err
		case os.IsExist(err):
			return http.StatusGone, err
		default:
			return http.StatusInternalServerError, err
		}
	}

	listing.Context = httpserver.Context{
		Root: c.Root,
		Req:  r,
		URL:  r.URL,
	}

	// Copy the query values into the Listing struct
	var limit int
	listing.Sort, listing.Order, limit, err = handleSortOrder(w, r, c.PathScope)
	if err != nil {
		return http.StatusBadRequest, err
	}

	listing.applySort()

	if limit > 0 && limit <= len(listing.Items) {
		listing.Items = listing.Items[:limit]
		listing.ItemsLimitedTo = limit
	}

	if strings.Contains(r.Header.Get("Accept"), "application/json") {
		marsh, err := json.Marshal(listing.Items)
		if err != nil {
			return http.StatusInternalServerError, err
		}

		w.Header().Set("Content-Type", "application/json; charset=utf-8")
		if _, err := w.Write(marsh); err != nil {
			return http.StatusInternalServerError, err
		}

		return http.StatusOK, nil
	}

	page := &p.Page{
		Info: &p.Info{
			Name:   listing.Name,
			Path:   i.RootPath,
			IsDir:  true,
			User:   u,
			Config: c,
			Data:   listing,
		},
	}

	if r.Header.Get("Minimal") == "true" {
		page.Minimal = true
	}

	return page.PrintAsHTML(w, "listing")
}

func (i Info) loadDirectoryContents(file http.File, path string, u *config.User) (*Listing, error) {
	files, err := file.Readdir(-1)
	if err != nil {
		return nil, err
	}

	listing := directoryListing(files, i.RootPath, path, u)
	return &listing, nil
}

func directoryListing(files []os.FileInfo, urlPath string, basePath string, u *config.User) Listing {
	var (
		fileinfos           []Info
		dirCount, fileCount int
	)

	for _, f := range files {
		name := f.Name()

		if f.IsDir() {
			name += "/"
			dirCount++
		} else {
			fileCount++
		}

		// Absolute URL
		url := url.URL{Path: basePath + name}
		fileinfos = append(fileinfos, Info{
			IsDir:       f.IsDir(),
			Name:        f.Name(),
			Size:        f.Size(),
			URL:         url.String(),
			ModTime:     f.ModTime().UTC(),
			Mode:        f.Mode(),
			UserAllowed: u.Allowed(url.String()),
		})
	}

	return Listing{
		Name:     path.Base(urlPath),
		Path:     urlPath,
		Items:    fileinfos,
		NumDirs:  dirCount,
		NumFiles: fileCount,
	}
}

// SimplifyMimeType returns the base type of a file
func SimplifyMimeType(name string) string {
	if strings.HasPrefix(name, "video") {
		return "video"
	}

	if strings.HasPrefix(name, "audio") {
		return "audio"
	}

	if strings.HasPrefix(name, "image") {
		return "image"
	}

	if strings.HasPrefix(name, "text") {
		return "text"
	}

	if strings.HasPrefix(name, "application/javascript") {
		return "text"
	}

	return "blob"
}