From 292ae22dcdf864935a66c9b2dcf892e7c2ef5d9e Mon Sep 17 00:00:00 2001
From: truewhile <62226914+truewhile@users.noreply.github.com>
Date: Sun, 6 Sep 2026 17:36:54 +0800
Subject: [PATCH] fix(sync): deduplicate remoteMeta by file ID to prevent
 deleting valid remote metadata copies

---
 internal/service/strm_sync.go      | 32 ++++++++++++++++++++----------
 internal/service/strm_sync_test.go | 24 ++++++++++++++++++++++
 2 files changed, 45 insertions(+), 11 deletions(-)

diff --git a/internal/service/strm_sync.go b/internal/service/strm_sync.go
index e06bbbc..2c84904 100644
--- a/internal/service/strm_sync.go
+++ b/internal/service/strm_sync.go
@@ -1341,6 +1341,7 @@ func (st *strmSyncState) localSha1Matches(path, remoteSha1 string) bool {
 }
 
 // recordRemoteMeta 记录远端存在的元数据索引、文件大小、文件引用及内容 SHA1（多副本聚合追加）。
+// 对同一文件 ID 严格去重，避免当 download_meta 与 upload_meta 同时开启时因重复记录引发误判与自杀式删除。
 func (st *strmSyncState) recordRemoteMeta(entry cloud.FileEntry, rel string) {
 	st.mu.Lock()
 	defer st.mu.Unlock()
@@ -1349,6 +1350,13 @@ func (st *strmSyncState) recordRemoteMeta(entry cloud.FileEntry, rel string) {
 	}
 	key := "m:" + rel
 	st.seenMeta[key] = true
+	if entry.ID != "" {
+		for _, existing := range st.remoteMeta[key] {
+			if existing.ID == entry.ID {
+				return
+			}
+		}
+	}
 	st.remoteMeta[key] = append(st.remoteMeta[key], remoteMetaItem{
 		ID:    entry.ID,
 		Size:  entry.Size,
@@ -1624,21 +1632,23 @@ func (st *strmSyncState) scanLocalMetaForUpload() error {
 					}
 				}
 			}
-			if matchedIdx >= 0 {
-				// 远端已存在完全一致的副本，跳过上传！
-				// 若远端还存在其他同名脏副本（副本总数 > 1），在 115 下收集待删除 ID，稍后按目录批量删除
-				if len(entries) > 1 && st.p.Provider == model.StrmProvider115 {
-					parentCID := st.uploadRemoteTarget(rel)
-					if parentCID != "" {
-						for i, it := range entries {
-							if i != matchedIdx && it.ID != "" {
-								pendingDeletes[parentCID] = append(pendingDeletes[parentCID], it.ID)
+				if matchedIdx >= 0 {
+					// 远端已存在完全一致的副本，跳过上传！
+					// 若远端还存在其他同名脏副本（副本总数 > 1），在 115 下收集待删除 ID，稍后按目录批量删除。
+					// 严禁将已命中的最新副本 ID (matchedID) 放入待删列表，杜绝误杀唯一有效副本。
+					if len(entries) > 1 && st.p.Provider == model.StrmProvider115 {
+						parentCID := st.uploadRemoteTarget(rel)
+						if parentCID != "" {
+							matchedID := entries[matchedIdx].ID
+							for i, it := range entries {
+								if i != matchedIdx && it.ID != "" && it.ID != matchedID {
+									pendingDeletes[parentCID] = append(pendingDeletes[parentCID], it.ID)
+								}
 							}
 						}
 					}
+					return nil
 				}
-				return nil
-			}
 		}
 
 		remoteTarget := st.uploadRemoteTarget(rel)
diff --git a/internal/service/strm_sync_test.go b/internal/service/strm_sync_test.go
index 8673234..23dedf0 100644
--- a/internal/service/strm_sync_test.go
+++ b/internal/service/strm_sync_test.go
@@ -1320,6 +1320,30 @@ func TestScanLocalMetaForUploadMultipleCopiesAllStale(t *testing.T) {
 	}
 }
 
+// TestRecordRemoteMetaDeduplication 验证当 download_meta 与 upload_meta 同时开启时，
+// 同一远端元数据被多次入账不会在 remoteMeta 中生成重复副本，杜绝误判自杀式删除。
+func TestRecordRemoteMetaDeduplication(t *testing.T) {
+	st := &strmSyncState{
+		seenMeta:   map[string]bool{},
+		remoteMeta: map[string][]remoteMetaItem{},
+	}
+	entry := cloud.FileEntry{
+		ID:    "unique-fid-1",
+		Name:  "test.nfo",
+		Size:  100,
+		Sha1:  "AAAABBBBCCCC",
+		MTime: 12345,
+	}
+	// 连续记录两次同一文件
+	st.recordRemoteMeta(entry, "dir/test.nfo")
+	st.recordRemoteMeta(entry, "dir/test.nfo")
+
+	items := st.remoteMeta["m:dir/test.nfo"]
+	if len(items) != 1 {
+		t.Fatalf("expected 1 item after duplicate record, got %d", len(items))
+	}
+}
+
 // TestWalk115AdaptiveHierarchicalFlatScan 验证自适应分治扁平化扫描：
 // 当根目录探测总数 >= 9500 时，系统自动分治展开单层直接子项，对各子目录分别执行扁平拉取，
 // 正确合并根目录直属文件与各子目录深层文件，突破 115 开放平台 10000 深度限制。