rclone/backend/googlephotos/albums.go
2019-07-02 15:26:55 +01:00

149 lines
3.2 KiB
Go

// This file contains the albums abstraction
package googlephotos
import (
"path"
"strings"
"sync"
"github.com/ncw/rclone/backend/googlephotos/api"
)
// All the albums
type albums struct {
mu sync.Mutex
dupes map[string][]*api.Album // duplicated names
byID map[string]*api.Album //..indexed by ID
byTitle map[string]*api.Album //..indexed by Title
path map[string][]string // partial album names to directory
}
// Create a new album
func newAlbums() *albums {
return &albums{
dupes: map[string][]*api.Album{},
byID: map[string]*api.Album{},
byTitle: map[string]*api.Album{},
path: map[string][]string{},
}
}
// add an album
func (as *albums) add(album *api.Album) {
// Munge the name of the album into a sensible path name
album.Title = path.Clean(album.Title)
if album.Title == "." || album.Title == "/" {
album.Title = addID("", album.ID)
}
as.mu.Lock()
as._add(album)
as.mu.Unlock()
}
// _add an album - call with lock held
func (as *albums) _add(album *api.Album) {
// update dupes by title
dupes := as.dupes[album.Title]
dupes = append(dupes, album)
as.dupes[album.Title] = dupes
// Dedupe the album name if necessary
if len(dupes) >= 2 {
// If this is the first dupe, then need to adjust the first one
if len(dupes) == 2 {
firstAlbum := dupes[0]
as._del(firstAlbum)
as._add(firstAlbum)
// undo add of firstAlbum to dupes
as.dupes[album.Title] = dupes
}
album.Title = addID(album.Title, album.ID)
}
// Store the new album
as.byID[album.ID] = album
as.byTitle[album.Title] = album
// Store the partial paths
dir, leaf := album.Title, ""
for dir != "" {
i := strings.LastIndex(dir, "/")
if i >= 0 {
dir, leaf = dir[:i], dir[i+1:]
} else {
dir, leaf = "", dir
}
dirs := as.path[dir]
found := false
for _, dir := range dirs {
if dir == leaf {
found = true
}
}
if !found {
as.path[dir] = append(as.path[dir], leaf)
}
}
}
// del an album
func (as *albums) del(album *api.Album) {
as.mu.Lock()
as._del(album)
as.mu.Unlock()
}
// _del an album - call with lock held
func (as *albums) _del(album *api.Album) {
// We leave in dupes so it doesn't cause albums to get renamed
// Remove from byID and byTitle
delete(as.byID, album.ID)
delete(as.byTitle, album.Title)
// Remove from paths
dir, leaf := album.Title, ""
for dir != "" {
// Can't delete if this dir exists anywhere in the path structure
if _, found := as.path[dir]; found {
break
}
i := strings.LastIndex(dir, "/")
if i >= 0 {
dir, leaf = dir[:i], dir[i+1:]
} else {
dir, leaf = "", dir
}
dirs := as.path[dir]
for i, dir := range dirs {
if dir == leaf {
dirs = append(dirs[:i], dirs[i+1:]...)
break
}
}
if len(dirs) == 0 {
delete(as.path, dir)
} else {
as.path[dir] = dirs
}
}
}
// get an album by title
func (as *albums) get(title string) (album *api.Album, ok bool) {
as.mu.Lock()
defer as.mu.Unlock()
album, ok = as.byTitle[title]
return album, ok
}
// getDirs gets directories below an album path
func (as *albums) getDirs(albumPath string) (dirs []string, ok bool) {
as.mu.Lock()
defer as.mu.Unlock()
dirs, ok = as.path[albumPath]
return dirs, ok
}