feat: per-link redirect type, password-protected links, branded visitor pages

- Redirects default to 302 so browsers stop permanently caching the hop —
  click analytics stay accurate and destination edits take effect for
  returning visitors. 301 is a per-link opt-in (create/edit/API).
- Links can carry a password: visitors get a branded unlock page at /:code
  and POST to /:code/unlock. Unlocks always redirect with 302.
- Missing, expired, and quota-limited links now show branded standalone
  visitor pages (404/410/429) instead of bouncing to the marketing site
  with ?error= query params.
- Clicks are recorded through the async pipeline with bot/crawler tagging
  (UA heuristics), GeoLite2 country lookup (ip-api fallback gated behind
  GEO_API_FALLBACK), and the IP_ANONYMIZE policy applied at write time.
- Deletes stamp deleted_at for later hard-purge.
- Dashboard: redirect-type selector and password set/replace/remove in the
  edit form, lock badge on protected links.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

app.py

@@ -637,6 +637,21 @@ def parse_referrer(ref):
     if 'instagram' in r:                                   return 'Instagram'
     return 'Other'
 
+_BOT_UA_MARKERS = (
+    'bot', 'crawler', 'spider', 'slurp', 'curl', 'wget', 'python-requests',
+    'python-urllib', 'httpclient', 'go-http-client', 'okhttp', 'scrapy',
+    'headless', 'phantomjs', 'facebookexternalhit', 'whatsapp', 'telegrambot',
+    'discordbot', 'slackbot', 'linkedinbot', 'twitterbot', 'pinterest',
+    'preview', 'monitor', 'pingdom', 'uptime', 'postmanruntime', 'java/',
+)
+
+def is_bot_ua(ua):
+    """Heuristic bot/crawler detection from the User-Agent string."""
+    if not ua:
+        return True
+    u = ua.lower()
+    return any(m in u for m in _BOT_UA_MARKERS)
+
 def get_client_ip():
     """Return the real client IP, honouring X-Forwarded-For from trusted proxies."""
     xff = request.headers.get('X-Forwarded-For', '')
@@ -644,42 +659,71 @@ def get_client_ip():
         return xff.split(',')[0].strip()
     return request.remote_addr or ''
 
-def get_country_for_request():
+def anonymize_ip(ip):
-    """Return a 2-letter ISO country code for the current request.
+    """Apply the configured IP_ANONYMIZE policy before an IP is stored.
+    'truncate' zeroes the host part; 'hash' keeps unique-visitor counting
+    possible without retaining the address itself."""
+    if not ip or IP_ANONYMIZE == 'none':
+        return ip
+    if IP_ANONYMIZE == 'hash':
+        return hashlib.sha256(ip.encode()).hexdigest()[:16]
+    if IP_ANONYMIZE == 'truncate':
+        if ':' in ip:
+            parts = ip.split(':')
+            return ':'.join(parts[:3]) + '::'
+        parts = ip.split('.')
+        if len(parts) == 4:
+            return '.'.join(parts[:3]) + '.0'
+    return ip
+
+# Local GeoLite2 country database (preferred over any network lookup).
+# Download GeoLite2-Country.mmdb from MaxMind and mount it at GEOIP_DB_PATH.
+_geoip_reader = None
+try:
+    import geoip2.database as _geoip2_db
+    if os.path.exists(GEOIP_DB_PATH):
+        _geoip_reader = _geoip2_db.Reader(GEOIP_DB_PATH)
+except Exception:
+    _geoip_reader = None
+
+def get_country_for_ip(ip):
+    """Return a 2-letter ISO country code for an IP address.
 
     Priority:
-    1. CF-IPCountry header (Cloudflare — zero-latency, most reliable)
+    1. Local MaxMind GeoLite2 database (offline, no rate limits, commercial-safe)
-    2. ip-api.com free JSON API (1-second timeout, fails gracefully)
+    2. ip-api.com free JSON API — only if GEO_API_FALLBACK=true (their free
-    Returns 'XX' if the IP is private/loopback, 'Unknown' on any failure.
+       tier is rate-limited and licensed for non-commercial use only)
+    Returns 'XX' for private/loopback IPs, 'Unknown' on any failure.
+    Called from the background click writer, never from the request path.
     """
-    import urllib.request as _ureq, json as _json
+    if not ip:
-
+        return 'Unknown'
-    cf = request.headers.get('CF-IPCountry', '').strip().upper()
-    if cf and len(cf) == 2 and cf.isalpha() and cf != 'XX':
-        return cf
-
-    ip = get_client_ip()
-    if not ip or ip in ('127.0.0.1', '::1'):
-        return 'XX'
-    # Skip RFC-1918 / loopback ranges — no point querying for private IPs
     try:
         import ipaddress
         parsed = ipaddress.ip_address(ip)
         if parsed.is_private or parsed.is_loopback or parsed.is_link_local:
             return 'XX'
     except ValueError:
-        pass
+        return 'Unknown'
+    if _geoip_reader:
         try:
+            return _geoip_reader.country(ip).country.iso_code or 'Unknown'
+        except Exception:
+            return 'Unknown'
+    if GEO_API_FALLBACK:
+        try:
+            import urllib.request as _ureq
             req = _ureq.Request(
                 f'http://ip-api.com/json/{ip}?fields=countryCode',
                 headers={'User-Agent': 'QRknit/1.0'}
             )
-        with _ureq.urlopen(req, timeout=1) as resp:
+            with _ureq.urlopen(req, timeout=2) as resp:
-            data = _json.loads(resp.read())
+                data = json.loads(resp.read())
             code = data.get('countryCode', '')
             return code if code else 'Unknown'
         except Exception:
             return 'Unknown'
+    return 'Unknown'
 
 def get_link_tags(conn, link_id):
     rows = conn.execute(
@@ -718,6 +762,8 @@ def format_link(row, conn):
         'clicks':     row['clicks'],
         'is_active':  row['is_active'],
         'is_pinned':  row['is_pinned'],
+        'redirect_type': row['redirect_type'] or 302,
+        'has_password':  bool(row['password_hash']),
         'short_url':  f"{BASE_URL}/{row['code']}",
         'qr_url':     f"{BASE_URL}/api/qr/{row['code']}",
         'tags':       get_link_tags(conn, row['id']),
@@ -855,6 +901,8 @@ def shorten():
     title         = (data.get('title') or '').strip()
     expires_at    = data.get('expires_at')
     tags          = data.get('tags', [])
+    redirect_type = data.get('redirect_type', 302)
+    password      = data.get('password') or ''
 
     if not long_url:
         return jsonify({'error': 'URL is required'}), 400
@@ -862,6 +910,9 @@ def shorten():
         return jsonify({'error': 'URL must start with http:// or https://'}), 400
     if custom_code and not re.match(r'^[a-zA-Z0-9]{1,20}$', custom_code):
         return jsonify({'error': 'Custom code must be 1–20 alphanumeric characters'}), 400
+    if redirect_type not in (301, 302, '301', '302'):
+        return jsonify({'error': 'redirect_type must be 301 or 302'}), 400
+    redirect_type = int(redirect_type)
 
     code = custom_code or generate_code(long_url)
 
@@ -883,10 +934,12 @@ def shorten():
             code = generate_code(long_url + str(time.time()))
 
         conn.execute(
-            'INSERT INTO links (code,long_url,title,created_at,expires_at,user_id) VALUES (?,?,?,?,?,?)',
+            'INSERT INTO links (code,long_url,title,created_at,expires_at,user_id,redirect_type,password_hash) '
+            'VALUES (?,?,?,?,?,?,?,?)',
             (code, long_url, title or None,
              datetime.now(timezone.utc).replace(tzinfo=None).isoformat(),
-             expires_at or None, session.get('user_id'))
+             expires_at or None, session.get('user_id'), redirect_type,
+             generate_password_hash(password) if password else None)
         )
         link_id = conn.execute('SELECT id FROM links WHERE code=?', (code,)).fetchone()['id']
         if tags:
@@ -898,6 +951,8 @@ def shorten():
         'long_url':  long_url,
         'title':     title,
         'tags':      tags,
+        'redirect_type': redirect_type,
+        'has_password':  bool(password),
         'qr_url':    f"{BASE_URL}/api/qr/{code}",
     }), 201
 
@@ -1005,6 +1060,14 @@ def edit_link(code):
         if 'title'      in data: updates['title']      = data['title'].strip() or None
         if 'expires_at' in data: updates['expires_at'] = data['expires_at'] or None
         if 'is_pinned'  in data: updates['is_pinned']  = 1 if data['is_pinned'] else 0
+        if 'redirect_type' in data:
+            if data['redirect_type'] not in (301, 302, '301', '302'):
+                return jsonify({'error': 'redirect_type must be 301 or 302'}), 400
+            updates['redirect_type'] = int(data['redirect_type'])
+        if 'password' in data:
+            # Non-empty string sets/updates the password; empty/null removes it
+            pw = data['password'] or ''
+            updates['password_hash'] = generate_password_hash(pw) if pw else None
 
         if updates:
             set_clause = ', '.join(f'{k}=?' for k in updates)
@@ -1024,7 +1087,7 @@ def delete_link(code):
         link = conn.execute('SELECT * FROM links WHERE code=?', (code,)).fetchone()
         if not link or not _can_access_link(link, conn):
             return jsonify({'error': 'Not found'}), 404
-        conn.execute('UPDATE links SET is_active=0 WHERE code=?', (code,))
+        conn.execute('UPDATE links SET is_active=0, deleted_at=? WHERE code=?', (now_iso(), code))
     return jsonify({'success': True})
 
 
@@ -1380,11 +1443,12 @@ def bulk_links():
     with get_db() as conn:
         if action == 'delete':
             if is_admin:
-                conn.execute(f'UPDATE links SET is_active=0 WHERE code IN ({placeholders})', codes)
+                conn.execute(f'UPDATE links SET is_active=0, deleted_at=? WHERE code IN ({placeholders})',
+                             [now_iso()] + list(codes))
             else:
                 conn.execute(
-                    f'UPDATE links SET is_active=0 WHERE code IN ({placeholders}) AND user_id=?',
+                    f'UPDATE links SET is_active=0, deleted_at=? WHERE code IN ({placeholders}) AND user_id=?',
-                    list(codes) + [user_id]
+                    [now_iso()] + list(codes) + [user_id]
                 )
             return jsonify({'deleted': len(codes)})
 
@@ -1810,9 +1874,95 @@ def sitemap_xml():
 
 
 # ─────────────────────────────────────────────
-# Redirect
+# Redirect — branded visitor pages, password gate, async click logging
 # ─────────────────────────────────────────────
 
+def _visitor_page(heading, message, body_html='', status=200):
+    """Branded standalone page shown to link visitors (expired, missing,
+    password-protected, …) — they never see the app or marketing site."""
+    html = f"""<!DOCTYPE html>
+<html lang="en"><head><meta charset="utf-8"><meta name="viewport" content="width=device-width,initial-scale=1">
+<meta name="robots" content="noindex"><title>{heading} — {APP_NAME}</title>
+<style>
+  :root {{ --bg:#0a0a12; --card:#12121e; --border:#23233a; --text:#e8e8f0; --muted:#6b6b80; --accent:#00b8d4; }}
+  * {{ box-sizing:border-box; margin:0; padding:0; }}
+  body {{ background:var(--bg); color:var(--text); font-family:'Segoe UI',system-ui,sans-serif;
+         min-height:100vh; display:flex; align-items:center; justify-content:center; padding:20px; }}
+  .card {{ background:var(--card); border:1px solid var(--border); border-radius:12px;
+           padding:40px 36px; max-width:420px; width:100%; text-align:center; }}
+  .brand {{ font-family:monospace; font-size:13px; letter-spacing:.14em; color:var(--muted);
+            text-transform:uppercase; margin-bottom:22px; }}
+  .brand b {{ color:var(--accent); }}
+  h1 {{ font-size:21px; margin-bottom:10px; }}
+  p {{ color:var(--muted); font-size:14px; line-height:1.6; }}
+  form {{ margin-top:22px; display:flex; flex-direction:column; gap:10px; }}
+  input[type=password] {{ background:var(--bg); border:1px solid var(--border); border-radius:8px;
+           color:var(--text); padding:11px 14px; font-size:14px; outline:none; }}
+  input[type=password]:focus {{ border-color:var(--accent); }}
+  button {{ background:var(--accent); border:none; border-radius:8px; color:#001318;
+            font-weight:600; padding:11px; font-size:14px; cursor:pointer; }}
+  .err {{ color:#ff5470; font-size:13px; margin-top:10px; }}
+</style></head><body>
+<div class="card">
+  <div class="brand"><b>▮</b> {APP_NAME}</div>
+  <h1>{heading}</h1>
+  <p>{message}</p>
+  {body_html}
+</div>
+</body></html>"""
+    return Response(html, status=status, mimetype='text/html',
+                    headers={'Cache-Control': 'no-store'})
+
+
+def _password_form(code, error=''):
+    err_html = f'<div class="err">{error}</div>' if error else ''
+    return _visitor_page(
+        'This link is password protected',
+        'Enter the password to continue to the destination.',
+        f'''<form method="POST" action="/{code}/unlock">
+  <input type="password" name="password" placeholder="Password" autofocus autocomplete="off">
+  <button type="submit">Unlock →</button>
+</form>{err_html}''',
+        status=200
+    )
+
+
+def _record_click(link_row):
+    """Capture request details and enqueue the click for the background writer."""
+    ua = request.headers.get('User-Agent', '')[:500]
+    cf = request.headers.get('CF-IPCountry', '').strip().upper()
+    item = {
+        'link_id':    link_row['id'],
+        'ts':         now_iso(),
+        'referrer':   request.referrer,
+        'ua':         ua,
+        'ip':         get_client_ip()[:45],
+        'cf_country': cf if (len(cf) == 2 and cf.isalpha() and cf != 'XX') else '',
+        'is_bot':     1 if is_bot_ua(ua) else 0,
+    }
+    try:
+        _click_queue.put_nowait(item)
+    except queue.Full:
+        pass
+
+
+def _check_link_gates(conn, link):
+    """Expiry and quota checks shared by the redirect and unlock routes.
+    Returns an error Response, or None if the link may be followed."""
+    if link['expires_at'] and link['expires_at'] < now_iso():
+        return _visitor_page('Link expired',
+                             'This short link has passed its expiry date and is no longer available.',
+                             status=410)
+    if link['user_id']:
+        plan        = get_user_plan(conn, link['user_id'])
+        click_limit = PLAN_LIMITS[plan]['monthly_clicks']
+        if click_limit is not None and get_user_monthly_clicks(conn, link['user_id']) >= click_limit:
+            return _visitor_page('Link temporarily unavailable',
+                                 'This link has reached its monthly click limit. Please try again later.',
+                                 status=429)
+    return None
+
+
 @app.route('/<code>')
 def redirect_link(code):
     if code in ('static', 'api', 'favicon.ico', 'robots.txt', 'sitemap.xml'):
@@ -1820,27 +1970,37 @@ def redirect_link(code):
     with get_db() as conn:
         link = conn.execute('SELECT * FROM links WHERE code=? AND is_active=1', (code,)).fetchone()
         if not link:
-            return redirect('/?error=not_found')
+            return _visitor_page('Link not found',
-        if link['expires_at'] and link['expires_at'] < datetime.now(timezone.utc).replace(tzinfo=None).isoformat():
+                                 "This short link doesn't exist or has been removed.",
-            return redirect('/?error=expired')
+                                 status=404)
+        gate = _check_link_gates(conn, link)
+        if gate:
+            return gate
+        if link['password_hash']:
+            return _password_form(code)
+        _record_click(link)
+        # 302 by default so browsers don't permanently cache the hop —
+        # keeps analytics accurate and destination edits effective. 301 is per-link opt-in.
+        return redirect(link['long_url'], code=link['redirect_type'] or 302)
 
-        # Monthly click quota check (skip for links with no owner)
-        if link['user_id']:
-            plan         = get_user_plan(conn, link['user_id'])
-            click_limit  = PLAN_LIMITS[plan]['monthly_clicks']
-            if click_limit is not None and get_user_monthly_clicks(conn, link['user_id']) >= click_limit:
-                return redirect('/?error=quota_exceeded')
 
-        country    = get_country_for_request()
+@app.route('/<code>/unlock', methods=['POST'])
-        client_ip  = get_client_ip()
+def unlock_link(code):
-        conn.execute(
+    with get_db() as conn:
-            'INSERT INTO clicks (link_id,clicked_at,referrer,user_agent,ip_address,country) VALUES (?,?,?,?,?,?)',
+        link = conn.execute('SELECT * FROM links WHERE code=? AND is_active=1', (code,)).fetchone()
-            (link['id'], datetime.now(timezone.utc).replace(tzinfo=None).isoformat(),
+        if not link or not link['password_hash']:
-             request.referrer, request.headers.get('User-Agent','')[:500],
+            return _visitor_page('Link not found',
-             client_ip[:45], country)
+                                 "This short link doesn't exist or has been removed.",
-        )
+                                 status=404)
-        conn.execute('UPDATE links SET clicks=clicks+1 WHERE id=?', (link['id'],))
+        gate = _check_link_gates(conn, link)
-        return redirect(link['long_url'], code=301)
+        if gate:
+            return gate
+        password = request.form.get('password', '')
+        if not check_password_hash(link['password_hash'], password):
+            return _password_form(code, error='Incorrect password — try again.')
+        _record_click(link)
+        # Always 302 for password links — the unlock must never be cached away
+        return redirect(link['long_url'], code=302)
 
 
 # ─────────────────────────────────────────────

index.html

@@ -1349,6 +1349,7 @@ function buildLinkItem(l) {
       </div>
       <div class="link-meta">
         ${ownerBadge}
+        ${l.has_password?'<span title="Password protected" style="font-size:12px">🔒</span>':''}
         <div class="link-clicks"><strong>${l.clicks}</strong> clicks${expNote}</div>
         <button class="copy-inline" title="Copy short URL"
                 onclick="event.stopPropagation();copyToClipboard('${l.short_url}')">copy</button>
@@ -1379,6 +1380,19 @@ function buildLinkItem(l) {
           <div class="edit-full"><label class="field-label">DESTINATION URL</label><input class="field-input" id="edit-url-${l.code}" value="${escHtml(l.long_url)}" onblur="autoFetchTitleForEdit('${l.code}')"></div>
           <div><label class="field-label">TITLE</label><input class="field-input" id="edit-title-${l.code}" value="${escHtml(l.title||'')}"></div>
           <div><label class="field-label">EXPIRY DATE</label><input class="field-input" type="date" id="edit-expiry-${l.code}" value="${(l.expires_at||'').slice(0,10)}"></div>
+          <div><label class="field-label">REDIRECT TYPE</label>
+            <select class="field-input" id="edit-rt-${l.code}">
+              <option value="302"${l.redirect_type==301?'':' selected'}>302 — Temporary (recommended)</option>
+              <option value="301"${l.redirect_type==301?' selected':''}>301 — Permanent (browsers cache)</option>
+            </select>
+          </div>
+          <div><label class="field-label">PASSWORD ${l.has_password?'<span style="color:var(--accent)">● set</span>':''}</label>
+            <div style="display:flex;gap:6px">
+              <input class="field-input" type="password" id="edit-pw-${l.code}" autocomplete="new-password" style="flex:1"
+                     placeholder="${l.has_password?'Unchanged — type to replace':'None — type to protect'}">
+              ${l.has_password?`<button class="btn-sm danger" onclick="removeLinkPassword('${l.code}')" title="Remove password protection">✕</button>`:''}
+            </div>
+          </div>
           <div class="edit-full"><label class="field-label">TAGS (comma separated)</label><input class="field-input" id="edit-tags-${l.code}" value="${(l.tags||[]).map(t=>t.name).join(', ')}"></div>
         </div>
         <div class="edit-actions">
@@ -1390,6 +1404,9 @@ function buildLinkItem(l) {
         <div class="analytics-header">
           <div class="analytics-title">CLICK ANALYTICS</div>
           <div style="display:flex;align-items:center;gap:8px">
+            <label style="display:flex;align-items:center;gap:4px;font-size:10px;font-family:var(--font-mono);color:var(--muted);cursor:pointer;letter-spacing:.04em">
+              <input type="checkbox" id="bots-${l.code}" onchange="loadAnalytics('${l.code}', analyticsDaysByCode['${l.code}']||7)"> NO BOTS
+            </label>
             <div class="analytics-days">
               <button class="day-btn active" onclick="loadAnalytics('${l.code}',7,this)">7d</button>
               <button class="day-btn" onclick="loadAnalytics('${l.code}',30,this)">30d</button>
@@ -1469,8 +1486,12 @@ async function saveEdit(code) {
   const url    = document.getElementById(`edit-url-${code}`).value.trim();
   const title  = document.getElementById(`edit-title-${code}`).value.trim();
   const expiry = document.getElementById(`edit-expiry-${code}`).value;
+  const rt     = parseInt(document.getElementById(`edit-rt-${code}`).value);
+  const pw     = document.getElementById(`edit-pw-${code}`).value;
   const tags   = document.getElementById(`edit-tags-${code}`).value.split(',').map(t=>t.trim()).filter(Boolean);
-  const resp = await authFetch(`${BASE}/api/links/${code}`, {method:'PATCH',body:JSON.stringify({url,title,expires_at:expiry||null,tags})});
+  const body   = {url, title, expires_at: expiry||null, tags, redirect_type: rt};
+  if (pw) body.password = pw;  // omit = leave password unchanged
+  const resp = await authFetch(`${BASE}/api/links/${code}`, {method:'PATCH',body:JSON.stringify(body)});
   const data = await resp.json();
   if (!resp.ok) { toast(data.error||'Save failed','error'); return; }
   toast('Link updated!');
@@ -1481,6 +1502,18 @@ async function saveEdit(code) {
   loadStats(); loadTags();
 }
 
+async function removeLinkPassword(code) {
+  if (!confirm(`Remove password protection from /${code}?`)) return;
+  const resp = await authFetch(`${BASE}/api/links/${code}`, {method:'PATCH', body:JSON.stringify({password:''})});
+  const data = await resp.json();
+  if (!resp.ok) { toast(data.error||'Failed','error'); return; }
+  toast('Password removed');
+  const old = document.getElementById(`item-${code}`);
+  const fresh = buildLinkItem(data);
+  fresh.classList.add('expanded');
+  old.parentNode.replaceChild(fresh, old);
+}
+
 async function deleteLink(code) {
   if (!confirm(`Delete /${code}?`)) return;
   await authFetch(`${BASE}/api/links/${code}`, {method:'DELETE'});