feat: Custom Monitor-Auswahl im RDP Client

Neue "Custom..." Option im Multi-Monitor-Dropdown, die einen
Checkbox-Dialog öffnet zur manuellen Auswahl einzelner Monitore.
Löst das Problem, dass bei "2 Monitors" immer die linkesten
Monitore gewählt wurden statt der gewünschten.

Neue Komponenten:
- _get_monitor_details(): Erkennt Monitore via xfreerdp + xrandr
- MonitorSelectionDialog: Checkbox-Dialog für Monitor-Auswahl
- monitor_ids wird pro Verbindung gespeichert

Bugfix: Doppelter _add_keyboard_shortcuts_info() Aufruf entfernt

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

rdp_client.py

@@ -324,6 +324,60 @@ class RDPClient:
             pass
         return 1  # Default to 1 monitor if detection fails
     
+    def _get_monitor_details(self):
+        """Get detailed information about all available monitors using xfreerdp and xrandr"""
+        monitors = []
+
+        # Get xrandr output names for better readability
+        xrandr_names = {}
+        try:
+            result = subprocess.run(['xrandr', '--listmonitors'],
+                                   capture_output=True, text=True, timeout=5)
+            if result.returncode == 0:
+                for line in result.stdout.strip().split('\n')[1:]:  # Skip "Monitors: N" header
+                    # Format: " 0: +*eDP-1 1920/344x1200/215+0+0  eDP-1"
+                    parts = line.strip().split()
+                    if len(parts) >= 3:
+                        idx = int(parts[0].rstrip(':'))
+                        # Output name is after the +/* prefix
+                        name_part = parts[1]
+                        # Strip leading +, * characters
+                        output_name = name_part.lstrip('+*')
+                        xrandr_names[idx] = output_name
+        except Exception as e:
+            self.logger.warning(f"Could not get xrandr monitor names: {e}")
+
+        # Get xfreerdp monitor list for IDs, resolutions, positions
+        try:
+            result = subprocess.run(['xfreerdp', '/monitor-list'],
+                                   capture_output=True, text=True, timeout=5)
+            if result.returncode == 0:
+                for line in result.stdout.strip().split('\n'):
+                    cleaned_line = line.strip()
+                    is_primary = cleaned_line.startswith('*')
+                    cleaned_line = cleaned_line.replace('*', '').strip()
+
+                    if '[' in cleaned_line and ']' in cleaned_line and 'x' in cleaned_line and '+' in cleaned_line:
+                        parts = cleaned_line.split()
+                        if len(parts) >= 3:
+                            id_part = parts[0]  # [0]
+                            res_part = parts[1]  # 1920x1080
+                            pos_part = parts[2]  # +3840+0
+
+                            if '[' in id_part and ']' in id_part:
+                                monitor_id = int(id_part.strip('[]'))
+                                monitors.append({
+                                    'id': monitor_id,
+                                    'name': xrandr_names.get(monitor_id, f"Monitor {monitor_id}"),
+                                    'resolution': res_part,
+                                    'position': pos_part,
+                                    'is_primary': is_primary,
+                                })
+        except Exception as e:
+            self.logger.error(f"Could not get xfreerdp monitor list: {e}")
+
+        return monitors
+
     def _get_multimon_options(self):
         """Get available multi-monitor options based on system"""
         monitor_count = self._get_available_monitors_count()
@@ -334,6 +388,7 @@ class RDPClient:
             options.append(f"{i} Monitors")
         
         if monitor_count > 1:
+            options.append("Custom...")
             options.extend(["All Monitors", "Span"])
         
         return options
@@ -641,9 +696,6 @@ class RDPClient:
         # Add tooltip information for shortcuts
         self._add_keyboard_shortcuts_info()
     
-        # Add tooltip information for shortcuts
-        self._add_keyboard_shortcuts_info()
-    
     def _add_keyboard_shortcuts_info(self):
         """Add keyboard shortcuts information to the status bar or help"""
         def show_shortcuts_hint(event):
@@ -687,8 +739,9 @@ Tips:
 
 Multi-Monitor Support:
 • "2 Monitors" - Use first 2 monitors (0,1)
-• "3 Monitors" - Use first 3 monitors (0,1,2)  
+• "3 Monitors" - Use first 3 monitors (0,1,2)
 • "4 Monitors" - Use first 4 monitors (0,1,2,3)
+• "Custom..." - Choose specific monitors via dialog
 • "All Monitors" - Use all available monitors
 • "Span" - Span desktop across monitors
 • "No" - Single monitor only"""
@@ -718,7 +771,10 @@ Multi-Monitor Support:
         self.details_labels["domain"].config(text=conn.get("domain", "N/A"))
         self.details_labels["resolution"].config(text=conn.get("resolution", "1920x1080"))
         self.details_labels["color_depth"].config(text=f"{conn.get('color_depth', 32)}-bit")
-        self.details_labels["multimon"].config(text=conn.get("multimon", "No"))
+        multimon_text = conn.get("multimon", "No")
+        if multimon_text == "Custom..." and conn.get("monitor_ids"):
+            multimon_text = f"Custom (Monitors: {conn['monitor_ids']})"
+        self.details_labels["multimon"].config(text=multimon_text)
         self.details_labels["sound"].config(text=conn.get("sound", "Yes"))
         self.details_labels["clipboard"].config(text=conn.get("clipboard", "Yes"))
         self.details_labels["drives"].config(text=conn.get("drives", "No"))
@@ -928,12 +984,14 @@ Multi-Monitor Support:
                 
                 # Check monitor configuration first to determine resolution handling
                 multimon = conn.get("multimon", "No")
-                use_specific_monitors = multimon in ["2 Monitors", "3 Monitors", "4 Monitors"]
+                use_specific_monitors = multimon in ["2 Monitors", "3 Monitors", "4 Monitors", "Custom..."]
-                
+
                 # Get monitor list if needed
                 monitor_list = None
                 if use_specific_monitors:
-                    if multimon == "2 Monitors":
+                    if multimon == "Custom...":
+                        monitor_list = conn.get("monitor_ids", "0")
+                    elif multimon == "2 Monitors":
                         monitor_list = self._get_best_monitor_selection(2)
                     elif multimon == "3 Monitors":
                         monitor_list = self._get_best_monitor_selection(3)
@@ -1354,6 +1412,73 @@ Multi-Monitor Support:
         self.root.mainloop()
 
 
+class MonitorSelectionDialog:
+    """Dialog for selecting specific monitors via checkboxes"""
+
+    def __init__(self, parent, monitors, preselected_ids=None):
+        """
+        Args:
+            parent: Parent window
+            monitors: List of dicts with keys: id, name, resolution, position, is_primary
+            preselected_ids: List of monitor IDs to pre-check, or None for all
+        """
+        self.result = None  # Will be set to comma-separated IDs string on OK
+
+        self.dialog = tk.Toplevel(parent)
+        self.dialog.title("Select Monitors")
+        self.dialog.resizable(False, False)
+        self.dialog.transient(parent)
+        self.dialog.grab_set()
+
+        main_frame = ttk.Frame(self.dialog, padding="20")
+        main_frame.pack(fill=tk.BOTH, expand=True)
+
+        ttk.Label(main_frame, text="Select which monitors to use:",
+                  font=('Segoe UI', 10, 'bold')).pack(anchor=tk.W, pady=(0, 10))
+
+        # Build checkboxes for each monitor
+        self.check_vars = {}
+        for mon in monitors:
+            mid = mon['id']
+            primary_tag = "  (primary)" if mon['is_primary'] else ""
+            label = f"Monitor {mid}: {mon['name']}  {mon['resolution']}  {mon['position']}{primary_tag}"
+
+            var = tk.BooleanVar(value=(preselected_ids is None or mid in preselected_ids))
+            self.check_vars[mid] = var
+
+            cb = ttk.Checkbutton(main_frame, text=label, variable=var)
+            cb.pack(anchor=tk.W, pady=2)
+
+        # Buttons
+        btn_frame = ttk.Frame(main_frame)
+        btn_frame.pack(fill=tk.X, pady=(15, 0))
+
+        ttk.Button(btn_frame, text="Cancel", command=self._cancel).pack(side=tk.RIGHT, padx=(10, 0))
+        ttk.Button(btn_frame, text="OK", command=self._ok).pack(side=tk.RIGHT)
+
+        # Size and center dialog
+        self.dialog.update_idletasks()
+        w = self.dialog.winfo_reqwidth() + 40
+        h = self.dialog.winfo_reqheight() + 20
+        x = (self.dialog.winfo_screenwidth() // 2) - (w // 2)
+        y = (self.dialog.winfo_screenheight() // 2) - (h // 2)
+        self.dialog.geometry(f"{w}x{h}+{x}+{y}")
+
+        self.dialog.wait_window()
+
+    def _ok(self):
+        selected = [mid for mid, var in self.check_vars.items() if var.get()]
+        if not selected:
+            messagebox.showwarning("No Selection", "Please select at least one monitor.",
+                                   parent=self.dialog)
+            return
+        self.result = ','.join(str(m) for m in sorted(selected))
+        self.dialog.destroy()
+
+    def _cancel(self):
+        self.dialog.destroy()
+
+
 class ConnectionDialog:
     def __init__(self, parent, title, initial_data=None, rdp_client=None):
         self.result = None
@@ -1449,15 +1574,31 @@ class ConnectionDialog:
             ("Gateway Mode:", "gateway", "combo", ["Auto", "RPC", "HTTP"]),
             ("Network Detection:", "network_auto_detect", "combo", ["Yes", "No"]),
         ]
-        
+
+        # Hidden field for custom monitor IDs
+        self.fields["monitor_ids"] = tk.StringVar(value=self.initial_data.get("monitor_ids", ""))
+
+        self._multimon_combo = None
+        self._monitor_ids_label = None
+
         for i, (label, field, widget_type, values) in enumerate(advanced_fields):
             row = i + 1  # Offset by 1 for description label
             ttk.Label(advanced_frame, text=label).grid(row=row, column=0, sticky=tk.W, pady=5, padx=(10, 5))
-            
+
             var = tk.StringVar(value=self.initial_data.get(field, values[0]))
             widget = ttk.Combobox(advanced_frame, textvariable=var, values=values, width=37, state="readonly")
             widget.grid(row=row, column=1, sticky=tk.W, pady=5, padx=(5, 10))
             self.fields[field] = var
+
+            if field == "multimon":
+                self._multimon_combo = widget
+                # Add label to show current custom monitor selection
+                self._monitor_ids_label = ttk.Label(advanced_frame, text="", font=('Segoe UI', 8, 'italic'))
+                self._monitor_ids_label.grid(row=row, column=2, sticky=tk.W, padx=(5, 0))
+                # Update label if initial data has Custom...
+                if self.initial_data.get("multimon") == "Custom..." and self.initial_data.get("monitor_ids"):
+                    self._monitor_ids_label.config(text=f"Monitors: {self.initial_data['monitor_ids']}")
+                widget.bind("<<ComboboxSelected>>", self._on_multimon_changed)
         
         # Performance fields
         performance_fields = [
@@ -1488,26 +1629,69 @@ class ConnectionDialog:
         ttk.Button(button_frame, text="Cancel", command=self._cancel).pack(side=tk.RIGHT, padx=(10, 0))
         ttk.Button(button_frame, text="Save", command=self._save).pack(side=tk.RIGHT)
     
+    def _on_multimon_changed(self, event=None):
+        """Handle multimon dropdown changes - open monitor dialog for Custom..."""
+        value = self.fields["multimon"].get()
+        if value == "Custom...":
+            if not self.rdp_client:
+                messagebox.showwarning("Error", "Cannot detect monitors.", parent=self.dialog)
+                return
+
+            monitors = self.rdp_client._get_monitor_details()
+            if not monitors:
+                messagebox.showwarning("No Monitors", "Could not detect any monitors.", parent=self.dialog)
+                self.fields["multimon"].set("No")
+                return
+
+            # Parse preselected IDs from stored value
+            preselected = None
+            stored = self.fields["monitor_ids"].get()
+            if stored:
+                try:
+                    preselected = [int(x.strip()) for x in stored.split(',')]
+                except ValueError:
+                    preselected = None
+
+            dlg = MonitorSelectionDialog(self.dialog, monitors, preselected)
+            if dlg.result:
+                self.fields["monitor_ids"].set(dlg.result)
+                self._monitor_ids_label.config(text=f"Monitors: {dlg.result}")
+            else:
+                # User cancelled - revert to previous selection if no monitor_ids stored
+                if not self.fields["monitor_ids"].get():
+                    self.fields["multimon"].set("No")
+                    self._monitor_ids_label.config(text="")
+        else:
+            # Clear monitor_ids and label for non-custom selections
+            self.fields["monitor_ids"].set("")
+            if self._monitor_ids_label:
+                self._monitor_ids_label.config(text="")
+
     def _save(self):
         """Save the connection"""
         # Validate required fields
         if not self.fields["name"].get().strip():
             messagebox.showerror("Error", "Connection name is required.")
             return
-        
+
         if not self.fields["server"].get().strip():
             messagebox.showerror("Error", "Server/IP is required.")
             return
-        
+
         if not self.fields["username"].get().strip():
             messagebox.showerror("Error", "Username is required.")
             return
-        
+
+        # Validate Custom... has monitor_ids
+        if self.fields["multimon"].get() == "Custom..." and not self.fields["monitor_ids"].get():
+            messagebox.showerror("Error", "Please select monitors for Custom... mode.", parent=self.dialog)
+            return
+
         # Collect data
         self.result = {}
         for field, var in self.fields.items():
             self.result[field] = var.get().strip()
-        
+
         self.dialog.destroy()
     
     def _cancel(self):