#include "behaviortree_cpp/bt_factory.h"

using namespace BT;

// clang-format off

static const char* xml_text = R"(

<root BTCPP_format="4" >

<BehaviorTree ID="MainTree">

<Sequence name="root">

<ThinkRuntimePort text="{the_answer}"/>

<SayRuntimePort message="{the_answer}" />

</Sequence>

</BehaviorTree>

</root>

)";

// clang-format on

class ThinkRuntimePort : public BT::SyncActionNode

{

public:

ThinkRuntimePort(const std::string& name, const BT::NodeConfig& config)

: BT::SyncActionNode(name, config)

{}

BT::NodeStatus tick() override

{

setOutput("text", "The answer is 42");

return NodeStatus::SUCCESS;

}

};

class SayRuntimePort : public BT::SyncActionNode

{

public:

SayRuntimePort(const std::string& name, const BT::NodeConfig& config)

: BT::SyncActionNode(name, config)

{}

// You must override the virtual function tick()

BT::NodeStatus tick() override

{

auto msg = getInput<std::string>("message");

if(!msg)

{

throw BT::RuntimeError("missing required input [message]: ", msg.error());

}

std::cout << "Robot says: " << msg.value() << std::endl;

return BT::NodeStatus::SUCCESS;

}

};

int main()

{

BehaviorTreeFactory factory;

//-------- register ports that might be defined at runtime --------

// more verbose way

PortsList think_ports = { BT::OutputPort<std::string>("text") };

factory.registerBuilder(

CreateManifest<ThinkRuntimePort>("ThinkRuntimePort", think_ports),

CreateBuilder<ThinkRuntimePort>());

// less verbose way

PortsList say_ports = { BT::InputPort<std::string>("message") };

factory.registerNodeType<SayRuntimePort>("SayRuntimePort", say_ports);

factory.registerBehaviorTreeFromText(xml_text);

auto tree = factory.createTree("MainTree");

tree.tickWhileRunning();

return 0;

}