feat: TKB shift scheduler — personnel shift planning web app

Full rewrite of METRO HMG for TKB tunnel department:
- People-based grid (18 TKB + 5 IT), year-long calendar
- Color-coded shift values (4/6/8/12/A/B/D/N/U/O)
- Drag-and-drop cells, multi-cell selection (click/ctrl/shift/drag)
- Right-click context menu with color palette
- Tunnel closure + Metro + D8 info rows (toggleable)
- Czech holidays highlighted with names
- PDF export (2-page A4 landscape, DejaVu font for Czech chars)
- Improvement proposals system
- Sticky headers (vertical + horizontal scroll)
- Cell value filter toggles in legend

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

web/export_excel.py

@@ -0,0 +1,108 @@
+#!/usr/bin/env python3
+"""Generate Excel export from saved schedule using template."""
+import json
+import sys
+import openpyxl
+from openpyxl.styles import PatternFill
+from copy import copy
+
+TEMPLATE = sys.argv[1]
+SCHEDULE = sys.argv[2]
+OUTPUT = sys.argv[3]
+
+STATION_ROWS = {
+    'DE': 13, 'HR': 14, 'MA': 15, 'ST': 16, 'MSA': 17, 'MUA': 18,
+    'NM': 19, 'FL': 20, 'JP': 21, 'ZL': 22, 'SN': 23, 'AN': 24,
+    'KN': 25, 'NA': 26, 'MSB': 27, 'NR': 28, 'FRB': 29, 'KR': 30,
+    'KC': 31, 'VY': 32, 'IP': 33, 'MUC': 34, 'HN': 35, 'FRC': 36,
+    'VL': 37, 'NH': 38, 'KB': 39,
+}
+
+NO_FILL = PatternFill(fill_type=None)
+
+with open(SCHEDULE) as f:
+    raw = json.load(f)
+
+data = raw['data'] if 'data' in raw and 'stations' not in raw else raw
+
+wb = openpyxl.load_workbook(TEMPLATE)
+ws = wb.active
+
+# Identify weekend columns: DEN row (row 11) has fill on weekends/holidays
+# Capture the DATA ROW fill (row 13) for those columns — it has the correct theme=0 gray
+weekend_cols = set()
+for col in range(7, 281):
+    den_cell = ws.cell(row=11, column=col)
+    if den_cell.fill and den_cell.fill.fill_type == 'solid':
+        weekend_cols.add(col)
+
+col_fills = {}
+for col in weekend_cols:
+    data_cell = ws.cell(row=13, column=col)
+    if data_cell.fill and data_cell.fill.fill_type == 'solid':
+        theme = data_cell.fill.fgColor.theme if hasattr(data_cell.fill.fgColor, 'theme') and isinstance(data_cell.fill.fgColor.theme, int) else None
+        if theme == 0:  # Gray weekend fill, not teal s/v fill
+            col_fills[col] = copy(data_cell.fill)
+
+for station in data['stations']:
+    row = STATION_ROWS.get(station['code'])
+    if not row:
+        continue
+
+    # Step 1: Clear all values
+    for col in range(7, 281):
+        ws.cell(row=row, column=col).value = None
+
+    # Step 2: Restore original column fills (weekends etc)
+    for col in range(7, 281):
+        if col in col_fills:
+            ws.cell(row=row, column=col).fill = copy(col_fills[col])
+        else:
+            ws.cell(row=row, column=col).fill = NO_FILL
+
+    # Step 3: Write data values (no extra fills — only weekend column fills from step 2)
+    for idx_str, cell_data in station['data'].items():
+        idx = int(idx_str)
+        col = idx + 7
+        if col < 7 or col > 280:
+            continue
+        val = cell_data.get('v')
+        if val is not None:
+            ws.cell(row=row, column=col).value = val
+
+# Add DEN row comments
+if 'dayComments' in data:
+    comments = data['dayComments']
+    # Handle both list format [{dayIdx, text}] and dict format {"idx": "text"}
+    if isinstance(comments, list):
+        for c in comments:
+            idx = c.get('dayIdx', 0)
+            text = c.get('text', '')
+            if text:
+                col = idx + 7
+                if 7 <= col <= 280:
+                    from openpyxl.comments import Comment
+                    ws.cell(row=11, column=col).comment = Comment(text, 'Metro HMG')
+    elif isinstance(comments, dict):
+        for idx_str, text in comments.items():
+            if text:
+                col = int(idx_str) + 7
+                if 7 <= col <= 280:
+                    from openpyxl.comments import Comment
+                    ws.cell(row=11, column=col).comment = Comment(text, 'Metro HMG')
+
+# Add cell comments (per station+day)
+if 'cellComments' in data:
+    from openpyxl.comments import Comment as XlComment
+    for c in data.get('cellComments', []):
+        code = c.get('stationCode', '')
+        idx = c.get('dayIdx', 0)
+        text = c.get('text', '')
+        row = STATION_ROWS.get(code)
+        if row and text:
+            col = idx + 7
+            if 7 <= col <= 280:
+                ws.cell(row=row, column=col).comment = XlComment(text, 'Metro HMG')
+
+wb.save(OUTPUT)
+print(f'Exported to {OUTPUT}', file=sys.stderr)