Add backup recovery center

ROADMAP.md

@@ -28,12 +28,12 @@
 
 ## v0.3 — Safe Repair
 
-- [ ] Dry-run repair plan
-- [ ] Backup before repair
-- [ ] Compatibility symlink creation
+- [x] Dry-run repair plan
+- [x] Backup before repair
+- [x] Compatibility symlink creation
 - [ ] Compatibility copy creation
 - [ ] Rename repair
-- [ ] Rollback log
+- [x] Rollback log and recovery center
 
 ## v0.4 — Migration Wizard
 

docs/design/backup-recovery-center.md

@@ -0,0 +1,30 @@
+# Backup recovery center
+
+## Problem
+
+An immediate undo button is not enough. A DJ may restart Serato Doctor, notice
+an issue later, or need to understand how much disk space safety snapshots use.
+
+## Architecture
+
+The recovery center reads the existing JSON manifests beneath
+`_Serato_/.serato-doctor-backups/`. It reports creation time, selected keeper,
+affected paths, restore status, and snapshot size. Invalid or incomplete backup
+folders are ignored rather than presented as restorable.
+
+Restore remains conservative: it only replaces a symbolic-link alias and
+refuses to overwrite a real file. A successful restore records its timestamp in
+the manifest so the UI cannot accidentally offer the same rollback twice.
+
+## Edge cases
+
+- No backup directory is treated as an empty history.
+- Malformed manifests do not prevent valid backups from loading.
+- Restored snapshots remain visible for audit purposes and disk accounting.
+- Backups can only be restored through the Serato library that owns them.
+
+## Tests
+
+- Backup history reports size and ready status.
+- Restore changes the persistent status to restored.
+- Static recovery assets are included in the package.

serato_doctor/repair.py

@@ -34,6 +34,20 @@ class RepairReceipt:
     replaced: Tuple[Path, ...]
 
 
+@dataclass(frozen=True)
+class BackupSummary:
+    path: Path
+    created_at: str
+    keeper: Path
+    replaced: Tuple[Path, ...]
+    size_bytes: int
+    restored_at: Optional[str]
+
+    @property
+    def status(self) -> str:
+        return "restored" if self.restored_at else "ready"
+
+
 def plan_duplicate_repair(
     keeper: Path, duplicates: Iterable[Path], serato_root: Path
 ) -> DuplicateRepairPlan:
@@ -124,9 +138,47 @@ def restore_backup(backup: Path) -> Tuple[Path, ...]:
         original.parent.mkdir(parents=True, exist_ok=True)
         shutil.copy2(saved, original)
         restored.append(original)
+    manifest["restored_at"] = datetime.now(timezone.utc).isoformat()
+    manifest_path.write_text(json.dumps(manifest, indent=2), encoding="utf-8")
     return tuple(restored)
 
 
+def list_backups(serato_root: Path) -> Tuple[BackupSummary, ...]:
+    backup_root = serato_root.expanduser().resolve() / BACKUP_FOLDER
+    if not backup_root.is_dir():
+        return ()
+    summaries = []
+    for backup in backup_root.iterdir():
+        manifest_path = backup / "manifest.json"
+        if not manifest_path.is_file():
+            continue
+        try:
+            manifest = json.loads(manifest_path.read_text(encoding="utf-8"))
+            replaced = tuple(
+                Path(entry["original"]) for entry in manifest["replaced"]
+            )
+            size = sum(
+                path.stat().st_size
+                for path in backup.rglob("*")
+                if path.is_file()
+            )
+            summaries.append(
+                BackupSummary(
+                    path=backup.resolve(),
+                    created_at=manifest["created_at"],
+                    keeper=Path(manifest["keeper"]),
+                    replaced=replaced,
+                    size_bytes=size,
+                    restored_at=manifest.get("restored_at"),
+                )
+            )
+        except (KeyError, OSError, TypeError, json.JSONDecodeError):
+            continue
+    return tuple(
+        sorted(summaries, key=lambda item: item.created_at, reverse=True)
+    )
+
+
 def rotate_backups(backup_root: Path, limit: Optional[int]) -> None:
     if limit is None or not backup_root.is_dir():
         return

serato_doctor/web.py

@@ -19,6 +19,7 @@ from serato_doctor.scanner import scan_filesystem
 from serato_doctor.repair import (
     BACKUP_FOLDER,
     apply_duplicate_repair,
+    list_backups,
     plan_duplicate_repair,
     restore_backup,
 )
@@ -29,6 +30,7 @@ DETAIL_LIMIT = 50
 STATIC_FILES = {
     "/": ("index.html", "text/html; charset=utf-8"),
     "/app.css": ("app.css", "text/css; charset=utf-8"),
+    "/recovery.css": ("recovery.css", "text/css; charset=utf-8"),
     "/app.js": ("app.js", "text/javascript; charset=utf-8"),
 }
 
@@ -269,6 +271,29 @@ def duplicate_repair(
     return result
 
 
+def backup_history(serato: Path) -> dict:
+    serato = serato.expanduser().resolve()
+    if not serato.is_dir():
+        raise ValueError(f"Serato folder does not exist: {serato}")
+    backups = list_backups(serato)
+    return {
+        "total": len(backups),
+        "size_bytes": sum(backup.size_bytes for backup in backups),
+        "items": [
+            {
+                "path": str(backup.path),
+                "created_at": backup.created_at,
+                "keeper": str(backup.keeper),
+                "replaced": [str(path) for path in backup.replaced],
+                "size_bytes": backup.size_bytes,
+                "status": backup.status,
+                "restored_at": backup.restored_at,
+            }
+            for backup in backups
+        ],
+    }
+
+
 class SeratoDoctorHandler(BaseHTTPRequestHandler):
     def do_GET(self) -> None:
         asset = STATIC_FILES.get(self.path)
@@ -293,6 +318,7 @@ class SeratoDoctorHandler(BaseHTTPRequestHandler):
             "/api/duplicates/preview",
             "/api/duplicates/apply",
             "/api/backups/restore",
+            "/api/backups",
         }
         if self.path not in allowed:
             self._json_response(404, {"error": "Not found"})
@@ -309,6 +335,8 @@ class SeratoDoctorHandler(BaseHTTPRequestHandler):
                 result = analyze_paths(
                     Path(payload["serato"]), Path(payload["music"]), roots
                 )
+            elif self.path == "/api/backups":
+                result = backup_history(Path(payload["serato"]))
             elif self.path == "/api/backups/restore":
                 serato = Path(payload["serato"]).expanduser().resolve()
                 backup = Path(payload["backup"]).expanduser().resolve()

serato_doctor/webui/app.js

@@ -15,6 +15,9 @@ const repairMessage = document.querySelector('#repair-message');
 const previewRepairButton = document.querySelector('#preview-repair');
 const applyRepairButton = document.querySelector('#apply-repair');
 const restoreRepairButton = document.querySelector('#restore-repair');
+const loadBackupsButton = document.querySelector('#load-backups');
+const backupSummary = document.querySelector('#backup-summary');
+const backupList = document.querySelector('#backup-list');
 let latestAnalysis = null;
 let selectedDuplicateGroup = null;
 let previewedRepair = null;
@@ -34,6 +37,52 @@ function escapeHtml(value) {
   }[character]));
 }
 
+function formatBytes(bytes) {
+  if (!bytes) return '0 B';
+  const units = ['B', 'KB', 'MB', 'GB', 'TB'];
+  const unit = Math.min(Math.floor(Math.log(bytes) / Math.log(1024)), units.length - 1);
+  return `${(bytes / (1024 ** unit)).toFixed(unit ? 1 : 0)} ${units[unit]}`;
+}
+
+function formatDate(value) {
+  const date = new Date(value);
+  return Number.isNaN(date.valueOf()) ? value : date.toLocaleString([], {dateStyle: 'medium', timeStyle: 'short'});
+}
+
+async function loadBackups() {
+  loadBackupsButton.disabled = true;
+  backupSummary.textContent = 'Looking for recovery snapshots…';
+  try {
+    const response = await fetch('/api/backups', {method: 'POST', headers: {'Content-Type': 'application/json'}, body: JSON.stringify({serato: expandHome(document.querySelector('#serato-path').value)})});
+    const data = await response.json();
+    if (!response.ok) throw new Error(data.error || 'Could not load backups');
+    backupSummary.textContent = `${data.total} backup${data.total === 1 ? '' : 's'} · ${formatBytes(data.size_bytes)} on disk`;
+    backupList.innerHTML = data.items.length ? data.items.map((backup) => `
+      <article class="backup-item">
+        <div><span class="backup-status ${backup.status}">${backup.status === 'restored' ? 'Restored' : 'Ready to restore'}</span><strong>${formatDate(backup.created_at)}</strong><small>Kept: ${escapeHtml(backup.keeper)}</small><small>${backup.replaced.length} original file${backup.replaced.length === 1 ? '' : 's'} · ${formatBytes(backup.size_bytes)}</small></div>
+        <button type="button" data-restore-backup="${escapeHtml(backup.path)}" ${backup.status === 'restored' ? 'disabled' : ''}>${backup.status === 'restored' ? 'Already restored' : 'Restore'}</button>
+      </article>
+    `).join('') : '<div class="empty-detail">No repair backups found for this library yet.</div>';
+  } catch (error) {
+    backupSummary.textContent = error.message;
+    backupList.innerHTML = '';
+  } finally { loadBackupsButton.disabled = false; }
+}
+
+loadBackupsButton.addEventListener('click', loadBackups);
+backupList.addEventListener('click', async (event) => {
+  const button = event.target.closest('[data-restore-backup]');
+  if (!button || button.disabled) return;
+  if (!window.confirm('Restore the original duplicate files from this backup? Existing real files will never be overwritten.')) return;
+  button.disabled = true; button.textContent = 'Restoring…';
+  try {
+    const response = await fetch('/api/backups/restore', {method: 'POST', headers: {'Content-Type': 'application/json'}, body: JSON.stringify({serato: expandHome(document.querySelector('#serato-path').value), backup: button.dataset.restoreBackup})});
+    const result = await response.json();
+    if (!response.ok) throw new Error(result.error || 'Restore failed');
+    await loadBackups();
+  } catch (error) { backupSummary.textContent = error.message; button.disabled = false; button.textContent = 'Restore'; }
+});
+
 function detailLines(item) {
   if (item.files) {
     return item.files.map((file) => `<li>${escapeHtml(file)}</li>`).join('');
@@ -127,6 +176,7 @@ applyRepairButton.addEventListener('click', async () => {
     repairMessage.textContent = `Cleanup complete. Restore backup: ${result.backup}`;
     previewRepairButton.disabled = true;
     restoreRepairButton.hidden = false;
+    await loadBackups();
   } catch (error) { repairMessage.textContent = error.message; applyRepairButton.disabled = false; }
 });
 
@@ -139,6 +189,7 @@ restoreRepairButton.addEventListener('click', async () => {
     if (!response.ok) throw new Error(result.error || 'Restore failed');
     repairMessage.textContent = `Restore complete. ${result.restored.length} original file(s) returned.`;
     restoreRepairButton.hidden = true;
+    await loadBackups();
   } catch (error) { repairMessage.textContent = error.message; restoreRepairButton.disabled = false; }
 });
 

serato_doctor/webui/index.html

@@ -6,6 +6,7 @@
   <meta name="color-scheme" content="dark">
   <title>Serato Doctor</title>
   <link rel="stylesheet" href="/app.css">
+  <link rel="stylesheet" href="/recovery.css">
 </head>
 <body>
   <div class="ambient ambient-one"></div>
@@ -20,6 +21,7 @@
         <a class="nav-item active" href="#dashboard"><span>⌁</span> Dashboard</a>
         <a class="nav-item" href="#scan"><span>◎</span> New analysis</a>
         <a class="nav-item" href="#diagnostics"><span>◇</span> Diagnostics</a>
+        <a class="nav-item" href="#recovery"><span>↶</span> Recovery</a>
       </nav>
       <div class="safety-card">
         <span class="safety-icon">✓</span>
@@ -55,6 +57,13 @@
         <div id="error-message" class="error" role="alert" hidden></div>
       </section>
 
+      <section id="recovery" class="recovery-panel panel">
+        <div class="section-heading"><div><p class="eyebrow">Safety net</p><h2>Backup recovery</h2></div><button id="load-backups" type="button">Check backups</button></div>
+        <p>Review every repair snapshot saved for this Serato library. Older backups remain available after restarting Serato Doctor.</p>
+        <div id="backup-summary" class="backup-summary">Enter your Serato folder above, then check backups.</div>
+        <div id="backup-list" class="backup-list"></div>
+      </section>
+
       <section id="dashboard" class="results" aria-live="polite" hidden>
         <div class="section-heading"><div><p class="eyebrow">Latest analysis</p><h2>Library health</h2></div><span id="analysis-time"></span></div>
         <div class="hero-grid">

serato_doctor/webui/recovery.css

@@ -0,0 +1 @@
+.recovery-panel{margin-top:18px;padding:25px}.recovery-panel>p{color:var(--muted);font-size:12px;line-height:1.6}.recovery-panel .section-heading button{border:1px solid rgba(155,135,245,.35);border-radius:10px;padding:9px 12px;background:rgba(155,135,245,.12);color:#ddd8fa;font:700 11px inherit;cursor:pointer}.recovery-panel button:disabled{opacity:.5;cursor:not-allowed}.backup-summary{padding:11px 13px;border-radius:11px;background:rgba(255,255,255,.03);color:#bfc4cf;font-size:11px;margin:15px 0 10px}.backup-list{display:grid;gap:9px}.backup-item{display:flex;align-items:center;justify-content:space-between;gap:18px;padding:14px;border:1px solid var(--line);border-radius:13px;background:rgba(255,255,255,.025)}.backup-item>div{min-width:0}.backup-item strong,.backup-item small{display:block}.backup-item strong{font-size:12px;margin:7px 0}.backup-item small{font-size:10px;color:var(--muted);line-height:1.5;overflow-wrap:anywhere}.backup-item>button{flex:0 0 auto;border:0;border-radius:10px;padding:10px 13px;background:#6f5bd0;color:#fff;font:700 11px inherit;cursor:pointer}.backup-status{display:inline-block;padding:4px 7px;border-radius:999px;font-size:9px;text-transform:uppercase;letter-spacing:.08em;color:var(--cyan);background:rgba(102,217,232,.1)}.backup-status.restored{color:#aeb4c2;background:rgba(255,255,255,.06)}@media(max-width:520px){.backup-item{align-items:stretch;flex-direction:column}.backup-item>button{width:100%}}

tests/test_repair.py

@@ -5,6 +5,7 @@ import pytest
 from serato_doctor.repair import (
     BACKUP_FOLDER,
     apply_duplicate_repair,
+    list_backups,
     plan_duplicate_repair,
     restore_backup,
     rotate_backups,
@@ -39,10 +40,16 @@ def test_duplicate_repair_backs_up_then_preserves_old_path_as_link(tmp_path):
     assert any((receipt.backup / "serato-metadata").rglob("House.crate"))
     assert any((receipt.backup / "serato-metadata").rglob("database V2"))
 
+    history = list_backups(serato)
+    assert len(history) == 1
+    assert history[0].status == "ready"
+    assert history[0].size_bytes > 0
+
     restored = restore_backup(receipt.backup)
     assert restored == (duplicate.resolve(),)
     assert not duplicate.is_symlink()
     assert duplicate.read_bytes() == b"duplicate"
+    assert list_backups(serato)[0].status == "restored"
 
 
 def test_plan_rejects_keeper_outside_duplicate_group(tmp_path):

tests/test_web.py

@@ -40,12 +40,13 @@ def test_web_analysis_rejects_missing_folders(tmp_path):
 def test_web_static_assets_are_declared_and_packaged():
     asset_root = Path(__file__).parents[1] / "serato_doctor" / "webui"
 
-    assert set(STATIC_FILES) == {"/", "/app.css", "/app.js"}
+    assert set(STATIC_FILES) == {"/", "/app.css", "/recovery.css", "/app.js"}
     assert all((asset_root / filename).is_file() for filename, _ in STATIC_FILES.values())
     html = (asset_root / "index.html").read_text(encoding="utf-8")
     assert "Missing tracks in Serato" in html
     assert "Old crate references" in html
     assert "Choose a diagnostic" in html
+    assert "Backup recovery" in html
     assert 'data-detail="database_missing_tracks"' in html
     assert 'data-detail="old_crate_references"' in html
     assert html.count('class="info-button"') >= 10