fix(config): preserve env files during managed updates

Co-Authored-By: Paperclip <noreply@paperclip.ing>

server/src/worktree-config.ts

@@ -2,6 +2,7 @@ import fs from "node:fs";
 import os from "node:os";
 import path from "node:path";
 import type { PaperclipConfig } from "@paperclipai/shared";
+import { updateEnvFileContents, writeEnvFileAtomicallyIfChanged } from "@paperclipai/shared/env-file";
 import { resolvePaperclipConfigPath, resolvePaperclipEnvPath } from "./paths.js";
 
 function nonEmpty(value: string | null | undefined): string | null {
@@ -76,73 +77,14 @@ function readEnvEntries(envPath: string): Record<string, string> {
   return parseEnvFile(fs.readFileSync(envPath, "utf8"));
 }
 
-function formatEnvEntries(entries: Record<string, string>): string {
+function emptyWorktreeEnvFileContents(): string {
   return [
     "# Paperclip environment variables",
     "# Generated by Paperclip worktree repair",
-    ...Object.entries(entries).map(([key, value]) => `${key}=${JSON.stringify(value)}`),
     "",
   ].join("\n");
 }
 
-function trailingEnvComment(rawValue: string): string {
-  let quote: "\"" | "'" | null = null;
-  let escaped = false;
-
-  for (let index = 0; index < rawValue.length; index += 1) {
-    const character = rawValue[index];
-    if (escaped) {
-      escaped = false;
-      continue;
-    }
-    if (quote === "\"" && character === "\\") {
-      escaped = true;
-      continue;
-    }
-    if (quote !== null) {
-      if (character === quote) quote = null;
-      continue;
-    }
-    if (character === "\"" || character === "'") {
-      quote = character;
-      continue;
-    }
-    if (character !== "#" || index === 0 || !/\s/.test(rawValue[index - 1] ?? "")) continue;
-
-    let commentStart = index;
-    while (commentStart > 0 && /\s/.test(rawValue[commentStart - 1] ?? "")) {
-      commentStart -= 1;
-    }
-    return rawValue.slice(commentStart);
-  }
-
-  return "";
-}
-
-function updateEnvFileContents(contents: string, entries: Record<string, string>): string {
-  const newline = contents.includes("\r\n") ? "\r\n" : "\n";
-  const missingEntries = new Map(Object.entries(entries));
-  const lines = contents.split(/\r?\n/).map((rawLine) => {
-    const match = rawLine.match(/^(\s*(?:export\s+)?)([A-Za-z_][A-Za-z0-9_]*)(\s*=\s*)(.*)$/);
-    if (!match) return rawLine;
-
-    const [, prefix, key, separator, rawValue] = match;
-    const value = entries[key];
-    if (value === undefined) return rawLine;
-
-    missingEntries.delete(key);
-    return `${prefix}${key}${separator}${JSON.stringify(value)}${trailingEnvComment(rawValue)}`;
-  });
-
-  const insertionIndex = lines.at(-1) === "" ? lines.length - 1 : lines.length;
-  lines.splice(
-    insertionIndex,
-    0,
-    ...Array.from(missingEntries, ([key, value]) => `${key}=${JSON.stringify(value)}`),
-  );
-  return lines.join(newline);
-}
-
 function isPathInside(candidatePath: string, rootPath: string): boolean {
   const candidate = path.resolve(candidatePath);
   const root = path.resolve(rootPath);
@@ -623,7 +565,6 @@ export function maybeRepairLegacyWorktreeConfigAndEnvFiles(): {
     }
   }
 
-  const existingEnvEntries = readEnvEntries(context.envPath);
   const managedEnvEntries: Record<string, string> = {
     PAPERCLIP_HOME: context.homeDir,
     PAPERCLIP_INSTANCE_ID: context.instanceId,
@@ -636,20 +577,18 @@ export function maybeRepairLegacyWorktreeConfigAndEnvFiles(): {
 
   process.env.PAPERCLIP_DB_BACKUP_ENABLED = "false";
 
-  const repairedEnv = Object.entries(managedEnvEntries).some(
-    ([key, value]) => existingEnvEntries[key] !== value,
+  const existingContents = fs.existsSync(context.envPath)
+    ? fs.readFileSync(context.envPath, "utf8")
+    : null;
+  const repairedContents = updateEnvFileContents(
+    existingContents ?? emptyWorktreeEnvFileContents(),
+    managedEnvEntries,
+    { valueEncoding: "json" },
   );
+  const repairedEnv = existingContents !== repairedContents;
 
   if (repairedEnv) {
-    fs.mkdirSync(path.dirname(context.envPath), { recursive: true });
-    const existingContents = fs.existsSync(context.envPath)
-      ? fs.readFileSync(context.envPath, "utf8")
-      : null;
-    const repairedContents =
-      existingContents === null
-        ? formatEnvEntries(managedEnvEntries)
-        : updateEnvFileContents(existingContents, managedEnvEntries);
-    fs.writeFileSync(context.envPath, repairedContents, { mode: 0o600 });
+    writeEnvFileAtomicallyIfChanged(context.envPath, existingContents, repairedContents);
   }
 
   return { repairedConfig, repairedEnv };