增加历史版本保存功能

src/utils/fileStore.ts

@@ -1,6 +1,6 @@
 import { createHash } from "node:crypto";
 import { mkdir, readFile, readdir, rename, rm, stat, writeFile } from "node:fs/promises";
-import { dirname, join } from "node:path";
+import { basename, dirname, join, relative } from "node:path";
 
 type JsonRecord = Record<string, unknown>;
 
@@ -18,6 +18,50 @@ export const atomicWriteFile = async (path: string, content: string) => {
   await rename(tempPath, path);
 };
 
+type HistoricalWriteOptions = {
+  afterWrite?: () => Promise<void> | void;
+  historyDir: string;
+  rootDir: string;
+};
+
+export const atomicWriteFileWithHistory = async (
+  path: string,
+  content: string,
+  options: HistoricalWriteOptions,
+) => {
+  const previous = await readTextFile(path);
+  if (previous === content) {
+    return { backupPath: null as string | null, changed: false };
+  }
+
+  let backupPath: string | null = null;
+  if (previous !== null) {
+    backupPath = buildHistoryBackupPath(path, options);
+    await atomicWriteFile(backupPath, previous);
+  }
+
+  try {
+    await atomicWriteFile(path, content);
+    await options.afterWrite?.();
+  } catch (error) {
+    try {
+      if (previous === null) {
+        await removeFileIfExists(path);
+      } else {
+        await atomicWriteFile(path, previous);
+      }
+    } catch (rollbackError) {
+      throw new AggregateError(
+        [error, rollbackError],
+        `write failed and rollback failed for ${path}`,
+      );
+    }
+    throw error;
+  }
+
+  return { backupPath, changed: true };
+};
+
 export const atomicWriteJson = async (path: string, value: JsonRecord | unknown[]) => {
   await atomicWriteFile(path, JSON.stringify(value, null, 2));
 };
@@ -109,3 +153,11 @@ export const slugify = (value: string) =>
     .replace(/[^a-z0-9._-]+/g, "-")
     .replace(/^-+|-+$/g, "")
     .slice(0, 64) || "entry";
+
+const buildHistoryBackupPath = (path: string, options: HistoricalWriteOptions) => {
+  const relativePath = relative(options.rootDir, path);
+  const scopedPath =
+    relativePath && !relativePath.startsWith("..") ? relativePath : basename(path);
+  const backupName = `${basename(path)}.${Date.now().toString(36)}.bak`;
+  return join(options.historyDir, dirname(scopedPath), backupName);
+};