Merge start/end dates into compact trade fair term column

web/index.html

@@ -1575,8 +1575,7 @@
                             <th><button type="button" class="bookmark-subpage__sort" data-trade-sort="thema">Thema</button></th>
                             <th><button type="button" class="bookmark-subpage__sort" data-trade-sort="stadt">Stadt</button></th>
                             <th><button type="button" class="bookmark-subpage__sort" data-trade-sort="bundesland">Bundesland</button></th>
-                            <th><button type="button" class="bookmark-subpage__sort" data-trade-sort="termin_start">Termin Start</button></th>
+                            <th><button type="button" class="bookmark-subpage__sort" data-trade-sort="termin">Termin</button></th>
-                            <th><button type="button" class="bookmark-subpage__sort" data-trade-sort="termin_ende">Termin Ende</button></th>
                             <th><button type="button" class="bookmark-subpage__sort" data-trade-sort="besucher">Besucher</button></th>
                             <th><button type="button" class="bookmark-subpage__sort" data-trade-sort="besucher_jahr">Besucher Jahr</button></th>
                             <th><button type="button" class="bookmark-subpage__sort" data-trade-sort="besucher_status">Besucher Status</button></th>

web/trade-fairs.js

@@ -24,8 +24,7 @@
     'thema',
     'stadt',
     'bundesland',
-    'termin_start',
+    'termin',
-    'termin_ende',
     'besucher',
     'besucher_jahr',
     'besucher_status',
@@ -706,8 +705,7 @@
     thema: 'text',
     stadt: 'text',
     bundesland: 'text',
-    termin_start: 'date',
+    termin: 'date',
-    termin_ende: 'date',
     besucher: 'number',
     besucher_jahr: 'number',
     besucher_status: 'text',
@@ -763,7 +761,8 @@
     return {
       ...row,
       tage_bis_start: getDaysUntil(row.termin_start),
-      zuletzt_gesucht_am: lastOpenedByTradeFair[getTradeFairOpenKey(row)] || null
+      zuletzt_gesucht_am: lastOpenedByTradeFair[getTradeFairOpenKey(row)] || null,
+      termin: row.termin_start || null
     };
   }
 
@@ -806,6 +805,40 @@
     return date.toLocaleDateString('de-DE');
   }
 
+  function formatTermRange(startIso, endIso) {
+    const start = toDate(startIso);
+    const end = toDate(endIso);
+
+    if (!start && !end) {
+      return 'k.A.';
+    }
+    if (start && !end) {
+      return formatDate(startIso);
+    }
+    if (!start && end) {
+      return formatDate(endIso);
+    }
+
+    const startDay = start.getDate();
+    const startMonth = start.getMonth() + 1;
+    const startYear = start.getFullYear();
+    const endDay = end.getDate();
+    const endMonth = end.getMonth() + 1;
+    const endYear = end.getFullYear();
+
+    if (startYear === endYear) {
+      if (startMonth === endMonth) {
+        if (startDay === endDay) {
+          return `${startDay}.${startMonth}.${startYear}`;
+        }
+        return `${startDay}.-${endDay}.${startMonth}.${startYear}`;
+      }
+      return `${startDay}.${startMonth}.-${endDay}.${endMonth}.${startYear}`;
+    }
+
+    return `${startDay}.${startMonth}.${startYear}-${endDay}.${endMonth}.${endYear}`;
+  }
+
   function matchesSearch(row, term) {
     if (!term) {
       return true;
@@ -1523,8 +1556,7 @@
       thema: createCell(row.thema, 'thema'),
       stadt: createCell(row.stadt, 'stadt'),
       bundesland: createCell(row.bundesland, 'bundesland'),
-      termin_start: createCell(formatDate(row.termin_start), 'termin_start'),
+      termin: createCell(formatTermRange(row.termin_start, row.termin_ende), 'termin'),
-      termin_ende: createCell(formatDate(row.termin_ende), 'termin_ende'),
       besucher: createCell(formatNumber(row.besucher), 'besucher'),
       besucher_jahr: createCell(formatNumber(row.besucher_jahr), 'besucher_jahr'),
       besucher_status: createCell(row.besucher_status, 'besucher_status'),