[darwin-framework-tool] Add a prepare-commissioning command

examples/darwin-framework-tool/commands/pairing/Commands.h

@@ -22,6 +22,7 @@
 
 #include "OpenCommissioningWindowCommand.h"
 #include "PairingCommandBridge.h"
+#include "PrepareCommissioningCommand.h"
 
 class PairCode : public PairingCommandBridge
 {
@@ -71,6 +72,7 @@ void registerCommandsPairing(Commands & commands)
         make_unique<PairBleThread>(),
         make_unique<Unpair>(),
         make_unique<OpenCommissioningWindowCommand>(),
+        make_unique<PrepareCommissioningCommand>(),
     };
 
     commands.Register(clusterName, clusterCommands);

examples/darwin-framework-tool/commands/pairing/PrepareCommissioningCommand.h

@@ -0,0 +1,53 @@
+/*
+ *   Copyright (c) 2022 Project CHIP Authors
+ *   All rights reserved.
+ *
+ *   Licensed under the Apache License, Version 2.0 (the "License");
+ *   you may not use this file except in compliance with the License.
+ *   You may obtain a copy of the License at
+ *
+ *       http://www.apache.org/licenses/LICENSE-2.0
+ *
+ *   Unless required by applicable law or agreed to in writing, software
+ *   distributed under the License is distributed on an "AS IS" BASIS,
+ *   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ *   See the License for the specific language governing permissions and
+ *   limitations under the License.
+ */
+
+#pragma once
+
+#import <Matter/Matter.h>
+
+#include "../common/CHIPCommandBridge.h"
+
+#import "MTRError_Utils.h"
+
+class PrepareCommissioningCommand : public CHIPCommandBridge {
+public:
+    PrepareCommissioningCommand()
+        : CHIPCommandBridge("prepare-commissioning")
+    {
+    }
+
+protected:
+    /////////// CHIPCommandBridge Interface /////////
+    CHIP_ERROR RunCommand() override
+    {
+        auto * controller = CurrentCommissioner();
+        NSError * error;
+        if (![controller prepareCommissioningSession:&error]) {
+            auto err = MTRErrorToCHIPErrorCode(error);
+            SetCommandExitStatus(err);
+            return err;
+        }
+
+        // In interactive mode, we don't want to block the UI until the end of `GetWaitDuration`. So returns early.
+        if (IsInteractive()) {
+            SetCommandExitStatus(CHIP_NO_ERROR);
+        }
+        return CHIP_NO_ERROR;
+    }
+
+    chip::System::Clock::Timeout GetWaitDuration() const override { return chip::System::Clock::Seconds16(30); }
+};