Fix monitor selection: resolve /f and /monitors: parameter conflict

Root cause: /f (fullscreen) parameter conflicts with /monitors: in FreeRDP 2.11.5
causing specific monitor selection to fall back to single monitor display.

Changes:
- Reorder command generation to check monitor config before resolution
- Skip /f when using specific monitor selection (/monitors:1,2 or /monitors:1,2,0)
- Keep /f only for 'All Monitors' and single monitor scenarios
- Add test script to validate new command generation logic

This should fix the issue where:
- 'All Monitors' works correctly (uses /f + /multimon)
- '2 Monitors' and '3 Monitors' were showing only 1 monitor

Expected result: /monitors:1,2 without /f should now properly display on 2 monitors

rdp_client.py

@@ -842,10 +842,17 @@ Multi-Monitor Support:
                 if conn.get("domain"):
                     cmd.append(f"/d:{conn['domain']}")
                 
-                # Resolution
+                # Check monitor configuration first to determine resolution handling
+                multimon = conn.get("multimon", "No")
+                use_specific_monitors = multimon in ["2 Monitors", "3 Monitors", "4 Monitors"]
+                
+                # Resolution - avoid /f with specific monitor selection due to conflicts
                 resolution = conn.get("resolution", "1920x1080")
-                if resolution == "Full Screen":
+                if resolution == "Full Screen" and not use_specific_monitors:
                     cmd.append("/f")
+                elif resolution == "Full Screen" and use_specific_monitors:
+                    # Don't use /f with specific monitors - let /monitors: determine the layout
+                    self.logger.info("Skipping /f (fullscreen) due to specific monitor selection")
                 else:
                     cmd.append(f"/size:{resolution}")
                 
@@ -853,11 +860,9 @@ Multi-Monitor Support:
                 color_depth = conn.get("color_depth", 32)
                 cmd.append(f"/bpp:{color_depth}")
                 
-                # Multiple monitors
+                # Multiple monitors - use /monitors: without /multimon for specific selection
-                multimon = conn.get("multimon", "No")
                 if multimon == "2 Monitors":
                     monitor_list = self._get_best_monitor_selection(2)
-                    # Try using /monitors without /multimon for specific monitor selection
                     cmd.append(f"/monitors:{monitor_list}")
                     self.logger.info(f"Using specific monitors for 2 monitors: {monitor_list}")
                 elif multimon == "3 Monitors":

test_fixed_monitor_logic.py

@@ -0,0 +1,87 @@
+#!/usr/bin/env python3
+
+import subprocess
+
+def get_best_monitor_selection(count):
+    """Get the best monitor selection based on layout"""
+    try:
+        result = subprocess.run(['xfreerdp', '/monitor-list'], 
+                              capture_output=True, text=True, timeout=5)
+        if result.returncode == 0:
+            lines = result.stdout.strip().split('\n')
+            monitors = []
+            
+            for line in lines:
+                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]
+                        pos_part = parts[2]
+                        if '[' in id_part and ']' in id_part:
+                            monitor_id = int(id_part.strip('[]'))
+                            x_pos = int(pos_part.split('+')[1])
+                            monitor_info = (monitor_id, x_pos, is_primary)
+                            monitors.append(monitor_info)
+            
+            monitors.sort(key=lambda x: x[1])
+            selected = [str(m[0]) for m in monitors[:count]]
+            return ','.join(selected)
+    except:
+        pass
+    
+    return ','.join([str(i) for i in range(count)])
+
+def test_new_command_logic():
+    print("=== Testing Fixed Monitor Selection Logic ===")
+    print()
+    
+    test_cases = [
+        ("2 Monitors", "Full Screen"),
+        ("3 Monitors", "Full Screen"),
+        ("All Monitors", "Full Screen"),
+        ("2 Monitors", "1920x1080"),
+    ]
+    
+    for multimon, resolution in test_cases:
+        print(f"Testing: {multimon} with {resolution}")
+        
+        cmd = ["xfreerdp", "/v:test-server", "/u:testuser", "/p:password"]
+        
+        # Check monitor configuration first
+        use_specific_monitors = multimon in ["2 Monitors", "3 Monitors", "4 Monitors"]
+        
+        # Resolution handling
+        if resolution == "Full Screen" and not use_specific_monitors:
+            cmd.append("/f")
+            print("  → Using /f (fullscreen)")
+        elif resolution == "Full Screen" and use_specific_monitors:
+            print("  → Skipping /f due to specific monitor selection")
+        else:
+            cmd.append(f"/size:{resolution}")
+            print(f"  → Using /size:{resolution}")
+        
+        cmd.append("/bpp:32")
+        
+        # Monitor handling
+        if multimon == "2 Monitors":
+            monitor_list = get_best_monitor_selection(2)
+            cmd.append(f"/monitors:{monitor_list}")
+            print(f"  → Using /monitors:{monitor_list}")
+        elif multimon == "3 Monitors":
+            monitor_list = get_best_monitor_selection(3)
+            cmd.append(f"/monitors:{monitor_list}")
+            print(f"  → Using /monitors:{monitor_list}")
+        elif multimon == "All Monitors":
+            cmd.append("/multimon")
+            print(f"  → Using /multimon")
+        
+        cmd_str = ' '.join(cmd).replace("/p:password", "/p:***")
+        print(f"  Command: {cmd_str}")
+        print()
+
+if __name__ == "__main__":
+    test_new_command_logic()