Full application rewrite

internal/organizer/organizer.go

@@ -0,0 +1,311 @@
+package organizer
+
+import (
+	"context"
+	"fmt"
+	"io"
+	"io/fs"
+	"log"
+	"os"
+	"path/filepath"
+	"strconv"
+	"strings"
+	"sync"
+
+	"github.com/fsnotify/fsnotify"
+
+	"github.com/derfenix/photocatalog/internal/metadata"
+)
+
+type MetaExtractor interface {
+	Extract(_ string, data io.Reader) (metadata.Metadata, error)
+}
+
+type Mode interface {
+	PlaceIt(sourcePath, targetPath string, mode os.FileMode) error
+}
+
+func NewOrganizer(mode Mode, source, target string) *Organizer {
+	return &Organizer{
+		mode:      mode,
+		sourceDir: source,
+		targetDir: target,
+
+		dirMode:  0777,
+		fileMode: 0644,
+
+		metaExtractors: map[string]MetaExtractor{
+			"":     &metadata.Default{},
+			"jpg":  metadata.Exif{},
+			"jpeg": metadata.Exif{},
+			"tiff": metadata.Exif{},
+		},
+	}
+}
+
+type Organizer struct {
+	mode Mode
+
+	sourceDir string
+	targetDir string
+
+	overwrite bool
+	dirMode   os.FileMode
+	fileMode  os.FileMode
+	errLogger func(error)
+
+	metaExtractors map[string]MetaExtractor
+}
+
+func (o *Organizer) WithOverwrite() *Organizer {
+	o.overwrite = true
+
+	return o
+}
+
+func (o *Organizer) WithDirMode(mode os.FileMode) *Organizer {
+	o.dirMode = mode
+
+	return o
+}
+
+func (o *Organizer) WithFileMode(mode os.FileMode) *Organizer {
+	o.fileMode = mode
+
+	return o
+}
+
+func (o *Organizer) WithErrLogger(f func(error)) *Organizer {
+	o.errLogger = f
+
+	return o
+}
+
+func (o *Organizer) logErr(err error) {
+	if o.errLogger != nil {
+		o.errLogger(err)
+	}
+}
+
+func (o *Organizer) Watch(ctx context.Context, wg *sync.WaitGroup) error {
+	watcher, err := fsnotify.NewWatcher()
+	if err != nil {
+		return fmt.Errorf("new watcher: %w", err)
+	}
+
+	if err := watcher.Add(o.sourceDir); err != nil {
+		return fmt.Errorf("add source dir to watcher: %w", err)
+	}
+
+	// Add all subfolders to the watcher.
+	err = filepath.WalkDir(o.sourceDir, func(path string, d fs.DirEntry, err error) error {
+		if path == o.sourceDir {
+			return nil
+		}
+
+		if d.IsDir() {
+			if err := watcher.Add(path); err != nil {
+				o.logErr(fmt.Errorf("add the directory %s to watcher: %w", path, err))
+			}
+		}
+
+		return nil
+	})
+	if err != nil {
+		return fmt.Errorf("add subdirs to watcher: %w", err)
+	}
+
+	wg.Add(2)
+
+	go func() {
+		defer wg.Done()
+
+		<-ctx.Done()
+
+		if err := watcher.Close(); err != nil {
+			o.logErr(fmt.Errorf("close watcher: %w", err))
+		}
+	}()
+
+	go func() {
+		defer wg.Done()
+
+		for {
+			select {
+			case event := <-watcher.Events:
+				if event.Op == fsnotify.Write {
+					stat, err := os.Stat(event.Name)
+					if err != nil {
+						o.logErr(fmt.Errorf("stat %s: %w", event.Name, err))
+
+						continue
+					}
+
+					// Add new directories to the watcher.
+					if stat.IsDir() {
+						if err := watcher.Add(event.Name); err != nil {
+							o.logErr(fmt.Errorf("watch dir: %w", err))
+						}
+
+						continue
+					}
+
+					if err := o.processFile(event.Name); err != nil {
+						o.logErr(fmt.Errorf("process file %s: %w", event.Name, err))
+					}
+				}
+
+			case <-ctx.Done():
+				return
+			}
+		}
+	}()
+
+	return nil
+}
+
+func (o *Organizer) FullSync(ctx context.Context) error {
+	err := filepath.WalkDir(o.sourceDir, func(path string, info fs.DirEntry, err error) error {
+		if ctx.Err() != nil {
+			return ctx.Err()
+		}
+
+		if info.IsDir() {
+			return nil
+		}
+
+		if err := o.processFile(path); err != nil {
+			return err
+		}
+
+		return nil
+	})
+	if err != nil {
+		return fmt.Errorf("walking source dir: %w", err)
+	}
+
+	return nil
+}
+
+func (o *Organizer) getMetaForPath(fp string) (metadata.Metadata, error) {
+	file, err := os.OpenFile(fp, os.O_RDONLY, os.ModePerm)
+	if err != nil {
+		return metadata.Metadata{}, fmt.Errorf("open file: %w", err)
+	}
+	defer func() {
+		_ = file.Close()
+	}()
+
+	meta, err := o.getMetadata(fp, file)
+	if err != nil {
+		return metadata.Metadata{}, fmt.Errorf("get metadata: %w", err)
+	}
+
+	return meta, nil
+}
+
+func (o *Organizer) getMetadata(fp string, data io.Reader) (metadata.Metadata, error) {
+	ext := strings.ToLower(filepath.Ext(fp))
+
+	if strings.HasPrefix(ext, ".") {
+		ext = ext[1:]
+	}
+
+	extractor, ok := o.metaExtractors[ext]
+	if !ok {
+		extractor = o.metaExtractors[""]
+	}
+
+	meta, err := extractor.Extract(fp, data)
+	if err != nil || meta.Created.IsZero() {
+		// Fallback to default extractor.
+		extractor = o.metaExtractors[""]
+
+		meta, err = extractor.Extract(fp, data)
+		if err != nil {
+			return metadata.Metadata{}, fmt.Errorf("extract metadata: %w", err)
+		}
+	}
+
+	return meta, nil
+}
+
+func (o *Organizer) processFile(sourcePath string) error {
+	meta, err := o.getMetaForPath(sourcePath)
+	if err != nil {
+		return err
+	}
+
+	targetPath, err := o.BuildTargetPath(sourcePath, meta)
+	if err != nil {
+		return fmt.Errorf("build target path: %w", err)
+	}
+
+	if pathExists(targetPath) && !o.overwrite {
+		return nil
+	}
+
+	if err := o.ensureTargetPath(filepath.Dir(targetPath)); err != nil {
+		return fmt.Errorf("ensure target path: %w", err)
+	}
+
+	if err := o.mode.PlaceIt(sourcePath, targetPath, o.fileMode); err != nil {
+		return fmt.Errorf("place file to new path: %w", err)
+	}
+
+	log.Printf("File %s placed at %s", sourcePath, targetPath)
+
+	return nil
+}
+
+func (o *Organizer) BuildTargetPath(sourcePath string, meta metadata.Metadata) (string, error) {
+	sourcePath, err := filepath.Rel(o.sourceDir, sourcePath)
+	if err != nil {
+		return "", fmt.Errorf("get a relative path: %w", err)
+	}
+
+	target := filepath.Join(
+		o.targetDir,
+		strconv.Itoa(meta.Created.Year()),
+		strconv.Itoa(int(meta.Created.Month())),
+		sourcePath,
+	)
+
+	return target, nil
+}
+
+func (o *Organizer) ensureTargetPath(targetPath string) error {
+	if pathExists(targetPath) {
+		return nil
+	}
+
+	relPath, err := filepath.Rel(o.targetDir, targetPath)
+	if err != nil {
+		return fmt.Errorf("get a relative path: %w", err)
+	}
+
+	dir := o.targetDir
+
+	for _, part := range strings.Split(relPath, string(filepath.Separator)) {
+		dir = filepath.Join(dir, part)
+
+		if err := os.Mkdir(dir, o.dirMode); err != nil && !os.IsExist(err) {
+			return fmt.Errorf("create target directory path at %s: %w", dir, err)
+		}
+	}
+
+	return nil
+}
+
+func pathExists(path string) bool {
+	_, err := os.Stat(path)
+	if err != nil {
+		if os.IsNotExist(err) {
+			return false
+		}
+
+		return true
+	}
+
+	return true
+}