#5780: Define new message type

include/imessagebus.h

@@ -50,6 +50,7 @@ class IMessage
         TextureChanged,
         ApplicationIsActiveQuery,
         FileOverwriteConfirmation,
+        FileSaveConfirmation,
         UnselectSelectionRequest,
         ManipulatorModeToggleRequest,
         ComponentSelectionModeToggleRequest,

libs/messages/FileSaveConfirmation.h

@@ -0,0 +1,80 @@
+#pragma once
+
+#include <stdexcept>
+#include "imessagebus.h"
+#include "iradiant.h"
+
+namespace radiant
+{
+
+/**
+ * Message sent when the backend code wants the user to confirm saving a modified file
+ * before a new map is loaded, with the option to Save the modified map, Discard the changes
+ * or to cancel the request.
+ * Senders: If this message stays unresponded the switch is allowed.
+ */
+class FileSaveConfirmation :
+    public radiant::IMessage
+{
+public:
+    enum class Action
+    {
+        SaveChanges,
+        DiscardChanges,
+        Cancel,
+    };
+
+private:
+    std::string _title;
+    std::string _message;
+
+    Action _action;
+
+public:
+    FileSaveConfirmation(const std::string& title, const std::string& message) :
+        _title(title),
+        _message(message),
+        _action(Action::DiscardChanges)
+    {}
+
+    const std::string& getTitle() const
+    {
+        return _title;
+    }
+
+    bool hasTitle() const
+    {
+        return !_title.empty();
+    }
+
+    const std::string& getMessage() const
+    {
+        return _message;
+    }
+
+    std::size_t getId() const override
+    {
+        return IMessage::Type::FileSaveConfirmation;
+    }
+
+    Action getChosenAction() const
+    {
+        return _action;
+    }
+
+    void setAction(Action action)
+    {
+        _action = action;
+    }
+
+    // Convenience method, creating an instance and dispatching it to the message bus, returning the answer
+    static Action SendAndReceiveAnswer(const std::string& message, const std::string& title = std::string())
+    {
+        FileSaveConfirmation msg(title, message);
+        GlobalRadiantCore().getMessageBus().sendMessage(msg);
+
+        return msg.getChosenAction();
+    }
+};
+
+}

tools/msvc/libs.vcxproj

@@ -172,6 +172,7 @@
     <ClInclude Include="..\..\libs\messages\CommandExecutionFailed.h" />
     <ClInclude Include="..\..\libs\messages\ComponentSelectionModeToggleRequest.h" />
     <ClInclude Include="..\..\libs\messages\FileOverwriteConfirmation.h" />
+    <ClInclude Include="..\..\libs\messages\FileSaveConfirmation.h" />
     <ClInclude Include="..\..\libs\messages\FileSelectionRequest.h" />
     <ClInclude Include="..\..\libs\messages\GameConfigNeededMessage.h" />
     <ClInclude Include="..\..\libs\messages\GridSnapRequest.h" />

tools/msvc/libs.vcxproj.filters

@@ -317,6 +317,9 @@
     <ClInclude Include="..\..\libs\messages\GridSnapRequest.h">
       <Filter>messages</Filter>
     </ClInclude>
+    <ClInclude Include="..\..\libs\messages\FileSaveConfirmation.h">
+      <Filter>messages</Filter>
+    </ClInclude>
   </ItemGroup>
   <ItemGroup>
     <Filter Include="util">