/**
* File History — backup files before modification
*
* On every write_file/edit_file/multi_edit, the original content is saved to:
* ~/.swagmanager/file-history/{sessionId}/{timestamp}-{basename}
*
* Limit: 100 backups per session (FIFO cleanup).
*/
import { existsSync, readFileSync, writeFileSync, mkdirSync, readdirSync, unlinkSync } from "fs";
import { join, basename } from "path";
import { homedir } from "os";
const HISTORY_BASE = join(homedir(), ".swagmanager", "file-history");
const MAX_BACKUPS_PER_SESSION = 100;
let currentSessionId: string | null = null;
export function setFileHistorySessionId(sessionId: string): void {
currentSessionId = sessionId;
}
function getSessionDir(): string | null {
if (!currentSessionId) return null;
const dir = join(HISTORY_BASE, currentSessionId);
if (!existsSync(dir)) mkdirSync(dir, { recursive: true });
return dir;
}
/**
* Save a backup of a file before it is modified.
* No-op if the file doesn't exist yet (new file creation).
*/
export function backupFile(filePath: string): void {
if (!currentSessionId) return;
if (!existsSync(filePath)) return;
try {
const dir = getSessionDir();
if (!dir) return;
const content = readFileSync(filePath);
const ts = Date.now();
const name = basename(filePath);
const backupName = `${ts}-${name}`;
const backupPath = join(dir, backupName);
writeFileSync(backupPath, content);
// FIFO cleanup
cleanupOldBackups(dir);
} catch {
// Best effort — don't fail the actual operation
}
}
function cleanupOldBackups(dir: string): void {
try {
const files = readdirSync(dir).sort();
if (files.length > MAX_BACKUPS_PER_SESSION) {
const toRemove = files.slice(0, files.length - MAX_BACKUPS_PER_SESSION);
for (const f of toRemove) {
try { unlinkSync(join(dir, f)); } catch { /* skip */ }
}
}
} catch { /* skip */ }
}
/**
* List backups for the current session.
*/
export function listBackups(): Array<{ name: string; path: string }> {
const dir = getSessionDir();
if (!dir || !existsSync(dir)) return [];
try {
return readdirSync(dir)
.sort()
.reverse()
.map(name => ({ name, path: join(dir, name) }));
} catch {
return [];
}
}
