Add first_seen/last_updated timestamps to track property freshness

Each property record now carries two date fields:
- first_seen: date the listing first appeared (preserved across runs)
- last_updated: date of the most recent scrape that included it

All 6 scrapers (Sreality, Realingo, Bezrealitky, iDNES, PSN, CityHome)
set these fields during scraping. Cached results preserve first_seen and
refresh last_updated. PSN and CityHome gain a load_previous() helper to
track first_seen across runs (they lacked caching before).

The merge script keeps the earliest first_seen and latest last_updated
when deduplicating listings across sources.

The HTML map now shows dates in popups ("Přidáno: DD.MM.YYYY"), displays
a green "NOVÉ" badge on newly discovered listings, and adds a "Přidáno"
dropdown filter (24h / 3 days / 7 days / 14 days) for spotting new ones.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

scrape_and_map.py

@@ -272,9 +272,13 @@ def scrape(max_pages: int | None = None, max_properties: int | None = None):
 
         # Check cache — if hash_id exists and price unchanged, reuse
         cached = cache.get(hash_id)
+        today = datetime.now().strftime("%Y-%m-%d")
         if cached and cached.get("price") == estate.get("price", 0):
             cache_hits += 1
             logger.debug(f"Cache hit for hash_id={hash_id}")
+            cached["last_updated"] = today
+            if "first_seen" not in cached:
+                cached["first_seen"] = today
             results.append(cached)
             continue
 
@@ -332,6 +336,11 @@ def scrape(max_pages: int | None = None, max_properties: int | None = None):
         disp_cb = estate.get("_disposition_cb") or estate.get("seo", {}).get("category_sub_cb")
         seo = estate.get("seo", {})
 
+        # Preserve first_seen from cache if this is a price-changed re-fetch
+        first_seen = today
+        if cached and "first_seen" in cached:
+            first_seen = cached["first_seen"]
+
         result = {
             "hash_id": hash_id,
             "name": estate.get("name", ""),
@@ -347,6 +356,8 @@ def scrape(max_pages: int | None = None, max_properties: int | None = None):
             "ownership": ownership,
             "url": sreality_url(hash_id, seo),
             "image": (estate.get("_links", {}).get("images", [{}])[0].get("href", "") if estate.get("_links", {}).get("images") else ""),
+            "first_seen": first_seen,
+            "last_updated": today,
         }
         results.append(result)
         details_fetched += 1
@@ -384,6 +395,12 @@ def generate_map(estates: list[dict], output_path: str = "mapa_bytu.html"):
         "6+": "#607D8B",     # grey-blue
     }
 
+    def fmt_date(d):
+        """Format ISO date (YYYY-MM-DD) to Czech format (DD.MM.YYYY)."""
+        if d and len(d) == 10:
+            return f"{d[8:10]}.{d[5:7]}.{d[:4]}"
+        return ""
+
     markers_js = ""
     for e in estates:
         color = color_map.get(e["disposition"], "#999999")
@@ -404,17 +421,42 @@ def generate_map(estates: list[dict], output_path: str = "mapa_bytu.html"):
         source_color = source_colors.get(source, "#999")
 
         hash_id = e.get("hash_id", "")
+        first_seen = e.get("first_seen", "")
+        last_updated = e.get("last_updated", "")
+
+        first_seen_fmt = fmt_date(first_seen)
+        last_updated_fmt = fmt_date(last_updated)
+
+        # "NOVÉ" badge if first_seen equals latest scrape date
+        new_badge = ""
+        if first_seen and first_seen == last_updated:
+            new_badge = (
+                '<span style="margin-left:6px;font-size:10px;background:#4CAF50;color:white;'
+                'padding:1px 5px;border-radius:3px;font-weight:bold;">NOVÉ</span>'
+            )
+
+        # Date info line
+        date_line = ""
+        if first_seen_fmt:
+            date_line = (
+                f'<div style="margin-top:4px;font-size:11px;color:#888;">'
+                f'Přidáno: {first_seen_fmt}'
+            )
+            if last_updated_fmt and last_updated != first_seen:
+                date_line += f' · Aktualizace: {last_updated_fmt}'
+            date_line += '</div>'
 
         popup = (
             f'<div style="min-width:280px;font-family:system-ui,sans-serif;" data-hashid="{hash_id}">'
             f'<b style="font-size:14px;">{format_price(e["price"])}</b>'
             f'<span style="margin-left:8px;font-size:11px;background:{source_color};color:white;'
-            f'padding:1px 6px;border-radius:3px;">{source_label}</span><br>'
+            f'padding:1px 6px;border-radius:3px;">{source_label}</span>{new_badge}<br>'
             f'<span style="color:#666;">{e["disposition"]} | {area_text} | {floor_text}</span>'
             f'{floor_note}<br><br>'
             f'<b>{e["locality"]}</b><br>'
             f'Stavba: {building_text}<br>'
-            f'Vlastnictví: {ownership_text}<br><br>'
+            f'Vlastnictví: {ownership_text}'
+            f'{date_line}<br>'
             f'<a href="{e["url"]}" target="_blank" '
             f'style="color:{source_color};text-decoration:none;font-weight:bold;">'
             f'→ Otevřít na {source_label}</a>'
@@ -440,7 +482,7 @@ def generate_map(estates: list[dict], output_path: str = "mapa_bytu.html"):
         is_fav = source in ("psn", "cityhome")
         marker_fn = "addHeartMarker" if is_fav else "addMarker"
         markers_js += (
-            f"  {marker_fn}({e['lat']}, {e['lon']}, '{color}', '{popup}', '{hash_id}');\n"
+            f"  {marker_fn}({e['lat']}, {e['lon']}, '{color}', '{popup}', '{hash_id}', '{first_seen}');\n"
         )
 
     # Build legend
@@ -552,6 +594,17 @@ def generate_map(estates: list[dict], output_path: str = "mapa_bytu.html"):
         </select>
       </label>
     </div>
+    <div style="margin-top:6px;">
+      <label>Přidáno:
+        <select id="first-seen-filter" onchange="applyFilters()">
+          <option value="all">Vše</option>
+          <option value="1">Posledních 24h</option>
+          <option value="3">Poslední 3 dny</option>
+          <option value="7">Poslední týden</option>
+          <option value="14">Posledních 14 dní</option>
+        </select>
+      </label>
+    </div>
   </div>
   <div class="filter-section">
     <div id="rating-counts" style="margin-bottom:6px;font-size:12px;color:#666;">
@@ -583,7 +636,7 @@ L.tileLayer('https://{{s}}.basemaps.cartocdn.com/light_only_labels/{{z}}/{{x}}/{
 
 var allMarkers = [];
 
-function addMarker(lat, lon, color, popup, hashId) {{
+function addMarker(lat, lon, color, popup, hashId, firstSeen) {{
   var marker = L.circleMarker([lat, lon], {{
     radius: 8,
     fillColor: color,
@@ -592,7 +645,7 @@ function addMarker(lat, lon, color, popup, hashId) {{
     opacity: 1,
     fillOpacity: 0.85,
   }}).bindPopup(popup);
-  marker._data = {{ lat: lat, lon: lon, color: color, hashId: hashId }};
+  marker._data = {{ lat: lat, lon: lon, color: color, hashId: hashId, firstSeen: firstSeen }};
   allMarkers.push(marker);
   marker.addTo(map);
 }}
@@ -612,11 +665,11 @@ function heartIcon(color) {{
   }});
 }}
 
-function addHeartMarker(lat, lon, color, popup, hashId) {{
+function addHeartMarker(lat, lon, color, popup, hashId, firstSeen) {{
   var marker = L.marker([lat, lon], {{
     icon: heartIcon(color),
   }}).bindPopup(popup);
-  marker._data = {{ lat: lat, lon: lon, color: color, hashId: hashId, isHeart: true }};
+  marker._data = {{ lat: lat, lon: lon, color: color, hashId: hashId, isHeart: true, firstSeen: firstSeen }};
   allMarkers.push(marker);
   marker.addTo(map);
 }}
@@ -807,13 +860,25 @@ map.on('popupopen', function(e) {{
 }});
 
 // ── Filters ────────────────────────────────────────────────────
+function daysAgoDate(days) {{
+  var d = new Date();
+  d.setDate(d.getDate() - days);
+  return d.toISOString().slice(0, 10);
+}}
+
 function applyFilters() {{
   var minFloor = parseInt(document.getElementById('min-floor').value);
   var maxPrice = parseInt(document.getElementById('max-price').value);
   var hideRejected = document.getElementById('hide-rejected').checked;
+  var firstSeenVal = document.getElementById('first-seen-filter').value;
   var ratings = loadRatings();
   var visible = 0;
 
+  var minFirstSeen = '';
+  if (firstSeenVal !== 'all') {{
+    minFirstSeen = daysAgoDate(parseInt(firstSeenVal));
+  }}
+
   allMarkers.forEach(function(m) {{
     var popup = m.getPopup().getContent();
     var floorMatch = popup.match(/(\\d+)\\. NP/);
@@ -826,6 +891,11 @@ function applyFilters() {{
     if (floor !== null && floor < minFloor) show = false;
     if (price > maxPrice) show = false;
 
+    // Date filter
+    if (minFirstSeen && m._data.firstSeen) {{
+      if (m._data.firstSeen < minFirstSeen) show = false;
+    }}
+
     var r = ratings[m._data.hashId];
     if (hideRejected && r && r.status === 'reject') show = false;