feat(assets): store note images in shared sibling assets directories

internal/vault/shared_images.go

@@ -0,0 +1,96 @@
+package vault
+
+import (
+	"fmt"
+	"os"
+	"path"
+	"path/filepath"
+	"strings"
+)
+
+type imageTransfer struct {
+	source, target string
+	data           []byte
+	created        bool
+	removeSource   bool
+	removed        bool
+}
+
+// 调用方持有写锁，并在后续笔记移动失败时撤回新副本。
+// 旧的独立附件仍由 Move 连同目录移动；共享图片只在其他笔记不再引用时移走原件。
+func (v *Vault) copyNoteImages(from, to string) (transfers []imageTransfer, targets map[string]string, err error) {
+	content, _, err := v.Read(from)
+	if err != nil {
+		return nil, nil, err
+	}
+	metadata := Analyze(from, content)
+	if len(metadata.Warnings) != 0 {
+		return nil, nil, fmt.Errorf("%w：%s 的元数据异常，无法确认图片引用", ErrInvalidPath, from)
+	}
+	entries, err := v.Tree()
+	if err != nil {
+		return nil, nil, err
+	}
+	used := map[string]bool{}
+	for _, entry := range entries {
+		if entry.Dir || !IsNote(entry.Path) || entry.Path == from {
+			continue
+		}
+		body, _, e := v.Read(entry.Path)
+		if e != nil {
+			return nil, nil, e
+		}
+		m := Analyze(entry.Path, body)
+		if len(m.Warnings) != 0 {
+			return nil, nil, fmt.Errorf("%w：%s 的元数据异常，无法确认图片引用", ErrInvalidPath, entry.Path)
+		}
+		for _, ref := range m.Assets {
+			used[ref.Target] = true
+		}
+	}
+	targets = map[string]string{}
+	for _, ref := range metadata.Assets {
+		if !IsImage(ref.Target) || strings.HasPrefix(ref.Target, AssetsDir(from)+"/") {
+			continue
+		}
+		if _, seen := targets[ref.Target]; seen {
+			continue
+		}
+		source, e := v.abs(ref.Target)
+		if e != nil {
+			return transfers, targets, e
+		}
+		info, e := os.Lstat(source)
+		if os.IsNotExist(e) {
+			continue // 已缺失的图片保留链接，由缺失检查报告。
+		}
+		if e != nil {
+			return transfers, targets, e
+		}
+		if !info.Mode().IsRegular() {
+			return transfers, targets, ErrInvalidPath
+		}
+		data, e := os.ReadFile(source)
+		if e != nil {
+			return transfers, targets, e
+		}
+		dest, exists, e := v.assetDestination(path.Join(path.Dir(to), "assets"), path.Base(ref.Target), data)
+		if e != nil {
+			return transfers, targets, e
+		}
+		targets[ref.Target] = dest
+		transfer := imageTransfer{source: ref.Target, target: dest, data: data, removeSource: !used[ref.Target] && ref.Target != dest}
+		if !exists {
+			full := filepath.Join(v.root, filepath.FromSlash(dest))
+			if e := os.MkdirAll(filepath.Dir(full), 0o755); e != nil {
+				return transfers, targets, e
+			}
+			if e := atomicWrite(full, data); e != nil {
+				return transfers, targets, e
+			}
+			transfer.created = true
+		}
+		transfers = append(transfers, transfer)
+	}
+	return transfers, targets, nil
+}